Final Project (19 Feb 09)

VJTI

A PROJECT REPORT ON “STUDY AND ELIMINATION OF DEFECTS USING QC-STORY & QCRT METHODOLOGY” CONDUCTED AT

Dept: Vehicle Product Unit SUBMITTED BY

NITESH R. GALFADE (D-050709) B. Tech Production Engineering. 2008-2009 Guided By: Prof.D.V.SHIRBHATE

Department of Production Engineering VeerMata Jijabai Technological Institute (Autonomous institute affiliated to University of Mumbai) Mumbai – 400019

CERTIFICATE Study & elimination of defects using QC story & QCRT methodology Nitesh Ranganath Galfade (D-050709)

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This is to certify that the project on “STUDY AND ELIMINATION OF DEFECTS USING QC-STORY & QCRT METHODOLOGY” In

VEHICLE PRODUCT UNIT Has been completed satisfactorily by

Mr. Nitesh R Galfade

(B.TECH PRODUCTION ENGINEERING)

Under the guidance of Mr. S. S. Kangutkar & Mr. D. S. Joshi ____________ ____________ COMPANY GUIDE Mr. S. S. KANGUTKAR D.V.SHIRBHATE Module Manager Quality Assurance Vehicle P. U. M&M

_____________ COMPANY GUIDE Mr. D. S. JOSHI

COLLEGE GUIDE Mr.

Manager Professor Quality Assurance V.J.T.I Vehicle P. U. M&M

EXAMINED ON _____________________

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ACKNOWLEDGEMENT It is my great pleasure to present this report, which will vouch for prolific and invaluable Training. I consider it an honored privilege to have undergone Inplant training at MAHINDRA & MAHINDRA, Vehicle Product Unit, and Kandivli unit. I thank my guide Prof. D.V.Shirbhate for his expert Guidance offered by him as regards the project. I would also like to thank Dr. Gaonkar (TPO) who helped me in arranging my training at MAHINDRA & MAHINDRA The training period of 6 months has enriched me with invaluable experience of the Industrial culture of the highest repute. This training period provided me with the Best opportunity to put my engineering knowledge to practical use. The knowledge and experience gained will always be highly cherished by me and have a lifelong influence on my career. I am deeply grateful to MR . S. S. Kangutkar & Mr. D. S. Joshi my project guide who was a great influence on me during the entire tenure of this training. This project would have seen the light of day if it wasn’t for this enthusiasm and the faith they reposed in me. I would also like to thank Mr. Dilip Bane (Training Officer) and also (HRD) for Arranging my Training in Vehicle Product Unit. I thank Mr. Sadique Shaikh, who zealously guided me at every juncture of need. Their altruistic co-operation, help and advice were found to be invaluable in most crucial stages of my project. I will remember his advice and ideas for Future progress. I would also thank other senior people of the shop floor and my worker friends who have shared their invaluable experience and taught me practical lessons. Nitesh R. Galfade

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Table of contents Sr.no

Topic

Page No

1.

Introduction to Mahindra Group & Kandivali Plant

5

2.

Introduction to my department

28

3.

My Daily Activities

36

4.

Manufacturing System Design

40

5.

Advanced Product Quality Planning

56

6.

QCRT Methodology

68

7.

Concern Resolution Process (QC Story)

71

8.

A Project on: Eliminating the defect loss due to Brake fluid level indicator Wire terminal backout

82

9.

A Project on: Eliminating the defect loss due to Clutch fluid leakage through joint at reservoir.

89

10.

A Project on: Eliminating the defect loss due to Diesel leakage from fuel tank bottom banjo joint.

101

11.

A Project on: Reduction of Scratches on Vehicle.

107

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Chapter 1 INTRODUCTION TO MAHINDRA GROUP & KANDIVALI PLANT

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INTRODUCTION

Mahindra and Mahindra Ltd., a premier Organization since 1945, inspires a sense of confidence and ruggedness among the people. M & M has two main operating divisions: The Automotive Division manufactures utility vehicles, light commercial vehicles and three wheelers. The Company has recently entered into a JV with Renault of France for the manufacture of a midsized sedan, the Logan, and with International Truck & Engine Corporation, USA, for manufacture of trucks and buses in India. The Tractor (Farm Equipment) Division makes agricultural tractors and implements that are used in conjunction with tractors, and has also ventured into manufacturing of industrial engines. The Tractor Division has won the coveted Deming Application Prize 2003, making it the only tractor manufacturing company in the world to secure this prize.

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Automotive Division Profile M&M's association with the automobile business dates back to 1945. The Company was incorporated in 1945 and was originally formed to manufacture utility vehicles for the Indian market, initially by importing and assembling Willys Jeep kits. The manufacture of utility vehicles commenced in 1954 in collaboration with Willys Overland Corporation and its successors, Kaiser Jeep Corporation and American Motor Corporation (now part of the DaimlerChrysler group). The Company commenced manufacturing Light Commercial Vehicles (LCV) in 1965. The Company has recently entered the three-wheeler market. Over the years, the Mahindra brands of vehicles have come to represent high quality, ruggedness, durability, reliability, easy maintenance and operational economy. These are the qualities that have endeared the vehicle to individuals as well as institutions like the Indian armed forces. M&M is the leader in the MUV business in the country since inception. M&M has comprehensive manufacturing facilities with high level of vertical integration. M&M's automotive division has four manufacturing plants, three in the state of Maharashtra and one in Andhra Pradesh. In Maharashtra, its plants in Mumbai and Nasik manufacture multi-utility vehicles, and engines are produced at the Igatpuri plant. Light commercial vehicles and three-wheelers are manufactured at the Company's plant in Zaheerabad in Andhra Pradesh. The Mumbai and Nasik plants with the R&D facility at Nasik are ISO/TS 16949 certified. The Mumbai plant has also been recommended for the TPM excellence award. The engine plant at Igatpuri has QS 9000 certification. The LCV & three wheeler plant at Zaheerabad have ISO 9001:1994 certification. Both of these plants are also working towards TS 16949 certification. The plants in Mumbai and Igatpuri are also ISO 14001 certified. M&M has a strong Research & Development set-up, with over 300 engineers in the automotive division. The Company's technical prowess is proven by negligible import content in the vehicle and by the design and development of a totally, from ground upward, new contemporary SUV - Scorpio.

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The division's marketing efforts are supported by a network of more than 275 dealers across the country, which are managed by 20 sales offices. Additionally, the division has a national network of authorized service stations and stockiest to meet customer needs for servicing and spare parts. Having conquered a substantial portion of India's semi-urban and rural markets, the division has in recent year’s secured significant success in urban regions following the introduction of premium MUVs like Bolero, and Scorpio. Scorpio is M&M's first indigenously developed Sports Utility Vehicle - an off road vehicle with car like comforts. The Scorpio was launched in June, 2002 and has been universally acclaimed. It was declared to be the "Car of the Year" by CNBC Auto car, BBC Wheels and Business Standard Motoring. M&M's automotive division also exports its products to several countries in Africa, Asia and European & Latin American countries.

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Plants under Automotive Division

AUTOMOTIVE SECTOR

KANDIVALI

NASHIK

ZAHEERABAD

Bolero camper Scorpio Champion Army vehicles Bolero Load king Maxi Truck Marshal Cab star Export Vehicles Maxx Voyager Maxx Pik up Utility Pik up Bolero Invader Pik Up CBC Major, Commander

IGATPURI Engines:XD3p-72hp 2600DX Petrol engine MDI 3200

Products of the Automotive Division of Mahindra and Mahindra Study & elimination of defects using QC story & QCRT methodology Nitesh Ranganath Galfade (D-050709)

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THE KANDIVALI PLANT This plant houses the administrative offices of the Automotive Division. The Automotive Division is divided into 6 product units.

Concept of Product Unit (PU): The concept of PU’s (Product Units) was evolved by Business Process Reengineering to systematize the processes of receiving vendor supplies, machining and assembly of distinct parts of the jeep.      

Body Product Unit Axle Product Unit Transmission Product Unit Engine Product Unit Foundry Product Unit Vehicle Product Unit

Each product unit is assisted by its own Supply Module (stores). Besides these P. U’s, following department are situated in the Automotive Division building:          

Human Resource Development (HRD) Production Planning & Control (PPC) Central Quality Assurance - vendor parts Management Development Services Personnel Department Material Controls Department (MCD) Electronic Data Processing (EDP) Accounts Industrial Engineering Design Department

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BODY PRODUCT UNIT

Raw Material Sheets

Press Shop Body Shop

Paint Shop

Accessories

Finished Body shell to trim Shop

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

PRESS SHOP :

The press shop manufactures the sheet metal components, which form the body shell and the chassis of the jeep. M.S. sheets of thickness varying from 1 – 5 mm are used as raw material. The Press Shop essentially has the capability to perform various pressing operations over the sheet metal specifically EN-4 (0.3%-C 1%-Mn 0.065-S & P 0.05-0.35%-Si) which is got cold rolled (majorly) at thicknesses about 1mm - 5mm. They follow TPM principle and believe in CLI C - Cleaning with meaning L - Lubricating I - Inspection The operations performed under the press shop include forming, bending, drawing, punching, blanking, shearing, flanging etc. Capacity is from 200T-1200T Press shop is mainly concerned with Body Parts of vehicle & carries out various operations like Cutting, Forming, Blocking, Punching, Embossing, Notching etc. This is carried out with the aid of various high & low tonnage presses. It is one of the important shops. Press working of different parts like accessories of the body of the Jeep parts required for body shell assembly. Main operations done in press shop are shearing, blanking, Punching, cut-off, flattening, forming, drawing, bending, flanging, trimming, joggling, etc. The press shop is divided into different areas like. I. Low bay area II. High bay area III. Tool repairs

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I. Low Bay Area: In low bay area there are presses of capacity 150 tons and less. These presses are used for small parts and for operations like blanking, punching cut off, trimming, bending, etc. This area includes: 1) Mechanical presses 2) Hydraulic press 3) Press brake

Shearing Section: Shearing section is considered as part of low bay. Here shearing of bigger sheets is done to the required size of the part. There are two shearing machine in this section both are of Godrej make.

II. High Bay Area: In high bay area there are presses of capacities ranging from 200 tons to 1200 tons. These presses are used for bigger and main jobs like bonnet, fender, front floor, rear floor etc. All presses are of mechanical types. These presses are used for operations like forming, drawing, trimming, punching, flanging etc. These are Godrej, HMT, Vickers, Fukui (Japan) presses.

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

BODY SHOP :

The Body Product Unit (P.U) is essentially providing the outer body cover for the vehicles. Their products being 1 MDI TC CDR Body Shell 2 MDI TC CL Body Shell 3 Single CAB 1190 Body Shell 4 Double CAB Body Shell 5 MM 540 Soft top Body Shell 6 MM 540 FRP top body shell 7 Single CAB Body Shell 8 Flat bed Cargo 9 SC Cargo 10 Double Cab Cargo 11 MaXX Cargo It is subdivided into • • •

Single CAB assembly area. Civilian Legend(CL)/Commander(CDR) assembly area. CO2 Welding area.

Here everything related to joining of the various pressed parts into nearly the final shape is done.

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1) CL Body: In CL body line the assembly is done without any welding fixtures. The process is fully based on experience of operators. First the small components are spot welded on pedestal welding machines and these parts are then assembled as final assembly with portable spot welding guns. The electrodes are of copper and are water-cooled. The main parts are body, rear panel, side panel, rear floor, front floor, cowl top, wheelhouse, etc. After the body is made it goes for CO2 welding at specified positions. The next stage is of drilling stage. It is done with portable drilling machines. After this there is a metal finishing area where the whole body is finished before sending for painting. While spot welding dent marks are remaining on body, that dent marks are removed by grinding. Also some high and low spots in spot welding are leveled properly. The body is then inspected and sent to the pretreatment shop.

2) MM Body Line: MM Body assembly is done with the welding fixtures. The main processes are spot welding and CO2 wielding. Spot wielding is done with both pedestal welding and portable spot welding guns. There are 12 welding fixtures used for carrying out the assembly of body. Following assemblies are done on fixtures: 1 Assembly of rear floor and extension. 2 Assembly of front floor and reinforcement. 3 Assembly of rear floor and front floor. 4 Assembly of right side wheel house panel. 5 Assembly of right side pillar. 6 Assembly of right side panel. 7 Assembly of left side wheel house panel. 8 Assembly of left side pillar. 9 Assembly of left side panel. 10 Assembly of cowl top. 11 Final assembly of above parts. 12 Spot welding for welding of remaining spots, which cannot be done at other welding fixtures.



Paint Shop :

Here the assembled body gets painted. It is a High risk area and very few people are allowed to enter. Here the body parts & other accessories are painted mainly for 3 purposes.  To provide an obstacle between metal & atmosphere and thus to protect the surface from corrosion.  To hide minor defects like scratches & welding marks.  To increase the aesthetic value of the vehicle.

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Axle Product Unit Raw Material Forgings

Hypoid Cell Machining

Raw Material Castings

Differential Case

Raw Material Castings

Raw Material Castings

Gear Carrier Machining

Hub Cell Machining

Heat Treatment

Pair Making

Gear Carrier Assembly Line

Axle Assembly Line

Final Axles to Vehicle PU Line

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Hypoid Line : Hypoid Pinion and Ring Gears as well as the Bevel Pinion Mates used in the differential assembly are machined from forgings. The preliminary operations for the ring gears and pinion mates include turning the blanks to the required dimensions on various CNC lathes. Hypoid Gear cutting is carried out on Gleason Hypoid Generator which is a highly specialized machine tool. Straight bevel gears of pinion mates are cut on Gleason Revacycle Rotary Broaching Machine. After gear cutting and the pinion and ring gears are lapped in a special lapping machine manufactured by Gleason, the pinion and ring gears are then meshed in a special machine and fitted to form pairs.

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Hub and Differential Case Machining Line



The principal machining processes in this line are:     

CNC turning of face and hub OD CNC boring of hub ID Drilling of Ring Gear mounting holes Form milling of Pinion Mate seats

Gear Carrier Machining Line :

The Gear Carrier casting is machined using the following machining processes:   

Plano Milling of Gear Carrier base End Milling of bearing cap resting faces

Pin Ball Yoke Machining Line :

The Ball Yoke is a forging, which is welded to the axle. The steering knuckle fits over this component and slides over its smooth spherical surface during steering. The various machining operations and their sequence are as follows:      

Copy turning outer surface and hub OD Boring axle shaft ID Straddle Milling sides Drilling, Counter Boring and Reaming Form grinding outer surface

Gear Carrier Assembly & Testing : This assembly is further sub-divided into:

1. Differential Case Sub-assembly : It consists of

  

Pinion mate and side gear assembly stage. Ring gear assembly stage. Press fitting of bearing to differential case.

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2. Hypoid Pinion & Gear Carrier Housing Sub-assembly :

It consists of the following stages:

  distance.   

Cleaning of Gear Carrier housing. 'A' Reading stage i.e. shims selection for pinion mounting Press fitting of outer race of taper bearing. Preload shim selection. Press fitting taper bearing and end yoke assembly.

3. Testing & inspection stage : It consists of

    

Actual test running of every Gear Carrier assembly. Visual inspection. Checking for backlash. Checking for loading and contact pattern.

Axle Assembly : The various stages and sub-assemblies in this assembly line are:  Welding of Ball Yoke to the axle end, Spring Bracket and Steering Setting Block to the axle tube.  Hub and Drum sub-assembly.  Assembly of Wheel Bearing Spindle & Steering Knuckle to Ball Yoke.  Assembly of Gear Carrier to the axle by weld filling 11 holes on the carrier arms.  Drum Fitment  Servo Testing

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Transmission Product Unit Raw Material Forging Blank

Raw Material Forging

Raw Material Casting

Gear Machining

Shaft Machining

Transmission Case Machining

Heat Treatment

H.T.

Grinding

Grinding

Transmission Assembly

Finished Transmission & Transfer Case Assembly to Vehicle P.U.

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

Transmission And Transfer Case (TTC) Machining Line:

In this line, castings of transmission and transfer cases are machined. The principal machining operations include:     

Rotary Surface Grinding Face Milling Precision Boring Drilling, Reaming and Tapping

Four Speed Gear And Shaft Line (4 Speed GSL)

Various spur and helical gears and transmission shafts required for 3-speed and 4-speed gear boxes are machined here. The various machines and processes studied here are as follows:         

CNC Turning Auto Turning Gear Hobbing Gear Shaping Gear Tooth Rounding & Chamfering Gear Shaving Gear Deburring CNC Cylindrical Grinding

Shift Rail And Shift Fork Machining Line : The principal machining processes in this line are:  

Milling cutter Center less grinding of shift rail Drilling and Reaming of rail bore on the shift fork

The two of the latest transmission units for the 5-speed gearboxes of Mahindra & Mahindra are NGT 530 and NGT 520, where NGT stands for New Generation Transmission.

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I. NGT 530:

The NGT 530 stands for New Gear Transmission cell producing 5speed gearbox giving an output of 30 N/m torque. The NGT 530 is the assembly line producing transmission boxes for MM models like Scorpio and Bolero. The assembly is of Nagara type, wherein a single worker does the complete assembly of a unit. NGT 530

NGT 520

II. NGT 520:

The NGT 520 stands for New Gear Transmission cell producing 5speed gearbox giving an output of 20 N/m torque. The NGT 520 is the assembly line producing transmission boxes for CL models. The assembly is of Line type, wherein the complete assembly is done in stages and by different workers at different workstations.

1

3

5

2

4

R

N

Gear Shift System

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Engine Product Unit

Raw Material Casting

Raw Material Casting

Cylinder Head Machining

Crankcase Machining

Engine Assembly

Engine Testing

Engine Dispatched to Vehicle PU

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

Crank Case Line Machining:

The crank case casting of spheroidal gray cast iron is cast in the foundry at M & M or procured from Menon Foundries in semi-finished condition and then machined in this shop. Machining crankcase is the most complex of all the processing operations. The various machines and processes in this line are as follows:       

Boring of crankshaft and camshaft Drilling of oil gallery hole Drilling of holes on the side face Drilling and Reaming of various other holes Plano milling of top face Boring of cylinder bore

Cylinder Head Machining Line : The principal machining processes in this line are:  



Plano Milling of sides Drilling and Reaming of various holes.

Engine Testing :

The engines after assembly they are sent for testing in the testing room. In engine testing room we can at a time test 25 engines. There are different parameters which are being tested before the engine is sent for dispatch.

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FOUNDRY PRODUCT UNIT Sand Receiving

Sand Mixing

Core Making

Sand Receivable Mould Making

Melting & Pouring

Fettling

Shot Blasting Dispatch

In this P.U casting of crankcase, cylinder head etc. are made. Some of the parts such as Transmission cases of Tractor division are also cast in this P.U Operations in Foundry are split up into following stages: • • • • • • • • •

Core sand preparation Core making and baking Core painting Molding sand preparation (Jolting and squeezing) Melting Molding Bay I Molding Bay II Fettling Inspection and then dispatch.

There are following products manufactured in the foundry product unit. Study & elimination of defects using QC story & QCRT methodology Nitesh Ranganath Galfade (D-050709)

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• • • • • •

Cylinder block. Fly wheel. Rear axle carrier. Transmission case. Cylinder head. Front Axle Support

All the units are interconnected with each other for making the final castings of the best quality. They work simultaneously with each other. The casting is formed in the following stages: • First the sand is prepared as per the requirements for the production of moulds or the cores. • This sand is then given to their respective departments for their production. • In the core making department the cores are made in the machines which are capable of forcing the sand under high pressure, compacting the sand and heating the sand to get bonded firmly. • In the mould preparing section the moulds are made mainly under the jolt-squeezing machines. Both cope and drag sections are made different machines. • Then these moulds are kept on the conveyer belts using cranes. • In the pouring section the metal is first melted away from the moulds and the temperature is recorded for each time. • Then the moulds are filled with the molten metal through the ladle. • After the mould is filled they lifted off from the conveyer belt and kept for cooling

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Chapter 2 INTRODUCTION TO MY DEPARTMENT

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VEHICLE PRODUCT UNIT

Fig 1.1. Layout of Vehicle Product Unit • • • •

This P.U consists of the following cells as shown in the above figure 1.1 Body Trim Cell Chassis Cell Body Drop Cell Test Cell This P.U handles the final assembly of the vehicle, testing of the vehicle and its dispatch. On joining the department I was given an in-depth orientation for 7 days. In this department various parts of vehicle are assembled together which comes from other departments & vendors. The specialty of this department is that all the models are manufactured on a single line. Study & elimination of defects using QC story & QCRT methodology Nitesh Ranganath Galfade (D-050709)

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 Different cells of Vehicle PU • • • • • • • •

Body Trim shop Chassis line Body drop Test cell FAI (Final Acceptance Inspection) CAI (Customer Acceptance Inspection) RFI (Ready For Inspection) Yard Check 

BODY TRIM SHOP

In this cell the body shell is received from paint shop. On this body shell various components are assembled. The entire interiors of the vehicle are assembled in this cell. The clutch, brake and accelerator pedal, the door locks, door glass, windshield glass, entire wiring, instrument panel and gauges are assembled in this cell besides the interior wall rexine is also trimmed in this cell. At the end of this assembly line there is a final inspection and every defect produced is attended and the trimmed body shell is transported to the assembly line.

 CHASSIS LINE In this section different parts of chassis are fitted. E.g. Fuel tank, axles, leaf springs, shock absorbers, steering gear box, stabilizer bar etc. • • •

•

Chassis are procured from the vendors. The chassis cell consists of 22 stages. Operations carried out when chassis is upside down: - Requalifying - Pipe fitment - Fitment of fuel tank and fuel lines, - Fitment of shock absorber - Fitment of Tie rod - Fitment of steering gear box - Fitment of leaf spring, - Axle fitment After this, the chassis is turned upside down with the help of a turning fixture, is placed on a conveyor & the following operations are carried out: - Fitment of brakes tubes - Fitment of exhaust system - Fitment of propeller shaft - Fitment of Steering column - Engine & Transmission sub-assembly - Dropping of Engine and Transmission on to the chassis - Buy-off

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

BODY DROP CELL

In this section the body shells coming from body trim cell are dropped on the chassis & fitted with body bolts. •

Operations carried out in Body drop cell: - Dropping of Body Shell on to chassis - Fitment of body shell with bolts - Fitment of steering column - Fitment of air filter - Vacuum testing & computerized filling of brake & clutch fluid - Fitment of cargo on chassis - Sub-assembly of radiator - Fitment of sub-assembled fender & grill assembly on to the chassis - Buy-Off Inspection of the left and right sides of vehicles - Fitment of tail lamp and head lamps - Connections of all wiring - Sub-assembly of tyre and wheel rim - Fitment of tyre on to vehicle - Filling of radiator coolant - Filling of diesel - Fitment of bonnet - Connections of EGR system - Final buy-off inspection for complete vehicle



TEST CELL

As a vehicle rolls down it goes to the test cell. In this cell different tests like side slip test, smoke test and roller test are carried out using digital instruments. And settings like wheel alignment, head light aiming, hand brake setting is carried out. Wheel alignment is done after checking side slip. Side slip is checked by a digital instrument. Here the front right wheel is passed over a sensor platform provided on the floor. This platform displays the value of side slip on the screen in “meters per kilometer”. The value of side slip should be within 4 m/km. If side slip is found beyond limits then according to that value the toe in is set. After wheel alignment is done the head light aiming is done, here the height of the head light beam is set according to the standards given by the designing department. After head light aiming is done the hand brake cable setting is done. After which roller testing is done.

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In roller testing following points are checked : Clutch operation and gear engagement Maximum Speed in each gear Gear noise and clutch noise Accelerator and decelerator test Speedometers check Engine Noise and vibration Emission test At the end of roller testing, all electrical are checked and under carriage inspection is done where fitment of bolts in the lower side of the vehicle and leakages are checked if any. The vehicle is then sent for Final Acceptance Inspection.       

FINAL ACCEPTANCE INSPECTION (FAI) In this section the shortage work is done besides major line rework if any. The shortage of every vehicle is written on the inspection sheet of that vehicle and the vehicle is not declared F.A.I O.K. Any defects or concerns produced on line are reworked in this stage. Then a sticker of FAI OK is stuck on the windshield glass of that vehicle if the vehicle is O.K. Then the vehicle is sent to the CAI section. 

CUSTOMER ACCEPTANCE INSPECTION (CAI)

CAI includes both the Static & Dynamic inspection. Here, first the inspector of CAI reads the inspection card for the defects mentioned in the card and cross checks whether these defects have been attended to, secondly they also check whether there is a sticker of F.A.I O.K. Then he takes the vehicle on the test track. After sufficient run he checks the gauges on the instrument panel, any noises etc. All defects observed are mentioned in the inspection card. During this run, Tractive Resistance (T.R.) of vehicle & parking brake performance is checked on different gradients provided near test track. To check the tractive resistance, the vehicle’s front wheels are brought on the Yellow line of T.R. gradient. A scale in meters is painted on this gradient to measure the travel of the vehicle. Then brakes are applied fully & engine is switched off. And then the brake pedal is released suddenly. So the vehicle rolls down from that gradient slowly over the painted scale. Somewhere the vehicle stops. Then the distance is measured on the painted scale provided on the gradient. The tractive resistance of any two wheel drive cab model vehicle should be minimum 9 meters and that of CL & CDR models (2WD) should be minimum 7 meters & that of four-wheel drive vehicle should be minimum 5 meters. If this distance is found less than required, then the wheels of that vehicle are jammed. So brake setting is to be done again.

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After this test, parking brake performance is checked on a 7.5 degrees gradient (for civilian vehicles). If a vehicle comes down from this gradient in parking brake applied condition, then the parking brake is to be tightened. Army Vehicles are checked on a special 15 degrees gradient for parking brake performance as these vehicles are being used in mountains where the roads are very steep. Then he checks the engine compartment for any type of fuel & brake oil leakage. Then the inspector brings that vehicle in the CAI line where the parking brake setting of the vehicles is done. Again every vehicle is checked for any type of leakage, electrical functions etc. If the vehicle is found OK, then it is sent for shower test (only in case of hard top vehicle) with a CAI tag on the windshield. If any leakage is found, then that portion is filled up with the sealant called Anabond (Silicon sealant). Then again the vehicle is checked for any type of water leakage inside the body. Here the OK vehicle is declared as Shower OK & a tag of Shower Test Done is stuck on the windshield.

 TOUCH UP In this shed the vehicle is checked for paint scratches that may have been formed while being assembled on line. The two painters touch up the scratches with the paint brushes and when all identified scratches have been touched up the painters stick Paint O. K. Sticker on the windshield. In case the vehicle is damaged or the scratch is a major one the vehicle is not applied the paint O. K. sticker until it is reworked using spraying gun. After this the vehicle is then given to the inspectors who check the traveler’s card whether all the defects have been attended to. Besides he also checks all the electrical and functionally important parts of the vehicle since it the final inspection. After the defect is identified it is reworked by an operator and the vehicle is then identified as O. K. by the inspector who sticks the final O. K. sticker on the windshield along with the Yard check O. K. sticker. 

YARD CHECK

It is the most important inspection from the quality point of view. After this the vehicles are dispatched directly. A maximum of 225 vehicles can be manufactured on a given day. In RFI, generally any 20 vehicles manufactured on the same day are checked. And if any defect is found in several vehicles then there are chances of the presence of that defect in all vehicles. Since the same operation is done by a single operator on that day. So in this condition, all the vehicles are checked by concerned officer or operator so that vehicles without defects can be supplied to the customer. Study & elimination of defects using QC story & QCRT methodology Nitesh Ranganath Galfade (D-050709)

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 READY FOR DISPATCH (RFD) The vehicles on which the Yard Check process is carried out are declared as RFD in SAP system. RFI and NOVA ‘C’ are the audits done by the Central Quality Assurance department. On the results of these two audits the performance of each product unit’s Quality Assurance cell is decided.

 READY FOR INSPECTION (RFI) Purpose •

This section is formed to ensure that the vehicles with zero defects are shipped to customers.

•

To identify all concerns (Customer perceived, fit, finish and performance subject to limited road testing using (10% to 15%) sample sizes and potential improvement concerns as well.

Objective •

Designed to launches.

•

Features large sampling

•

High confidence that low frequency will be identified as well as repetitive issues.

•

Increased probability of high quality units being shipped to customers.

improve

vehicle

quality

during

new

model

Methodology •

10-15% of the days production from various models are picked up PDI (Pre delivery inspection stage)

•

Vehicles are tested for static and dynamic tests based using check sheets.

•

Check sheets are generic in nature frequency concerns are also captured.

to

ensure

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 NEW OVERALL VEHICLE AUDITCUSTOMER (NOVA-C) In NOVA C everyday one vehicle is checked by an inspector. Here this vehicle is checked according to customer point of view. So the primary importance is given to the aesthetics of vehicle. Therefore the severity points given in RFI & in NOVA-C for a same problem are different. In short the exact difference between RFI & NOVA- C is, RFI is mainly concerned with points related to safety whereas NOVA-C gives more importance to aesthetics. e.g. a defect of Seat torn is found in the both RFI & NOVA-C, then the severity point given to this problem in RFI will be 4 and same in NOVA-C will be 9 out of 10.The reason behind this is, most of the customers check the vehicle from the aesthetic point of view. Here that vehicle is road tested for minimum 50 km outside the company. Then that vehicle is placed in NOVA-C cell. Here so many numbers of tube lights are provided. After these vehicle is fully washed by CTC chemical. Due to this every small dent & scratch becomes visible and tube lights aids to this. Then according to the data of defects in NOVA-C the corrective actions are taken to reduce the defects.

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Chapter 3 MY DAILY ACTIVITIES

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 DAILY ACTIVITES IN DEPARTMENT I am placed in the Quality Assurance department of the vehicle P.U. the main motto of our department is to ZERO DEFECT VEHICLES.  Daily visiting R.F.I and NOVA ‘C’ audit shed and checking

defects: The 10% of the vehicles produced per day per model are inspected by C.Q.A. inspectors .A computerized report of all the observed defects is generated in a software named as SAP (System Application and Products) which is accessible to all the Mahindra plants by the RFI inspectors at the end of their inspection. After generating a hard copy of the report I visit the RFI and NOVA-C shed and checks all the defects.  Understanding the defects and the possible cause for the defects: All the defects occurring in the reports are minutely studied and the photograph of each concern is taken. The photograph are used later to caution the concerned operator / vendor due to which the defect occurs. The operator is cautioned by giving an OPL.  Categorizing the defects as per the module and updating

the quality report: All the defects for the day are categorized according to their root cause. The modules under which the defects are categorized are as follows: Manufacturing: If the defect is a manual error. The operator is cautioned by giving an OPL with the photograph of is error if possible. E.g. forgot to tighten the joint with torque wrench. Vendor: The defects occurring due to vendor parts not meeting the required specifications are categorized under this module. E.g. R.A.P.B. bracket on chassis tilted. Design: If the defect is recurring and presenting almost all vehicles design department looks after the defect. Process: If the defect is due to inappropriate process or tools then it’s categorized under process and the process engg, takes action. E.g. Stabilizer bar washer getting damaged due to fouling with peg of conveyor. A specimen RFI report along with module is attached.

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 Attending the daily Quality meeting and giving feedback

about the defects observed : This meeting is held on daily basis to discuss the quality related issues. The entire cell officers, QA officials, supplier QA officials, PU Manger along with the process engineer attend the meeting .This meeting also gives me an exposure to professionalism of the executives and their managerial skills.

 Segregating defective parts from line and ensuring O. K. parts are given on line.  Checking defective parts with respect to the drawings.  Giving OPLs to operators for manual defects: OPL – One Point Lesson An OPL is a 5 to 10 minutes (normally take less than 15 minutes) lesson one topic on one sheet- means only one point illustrated on a sheet of paper, as many senses as possible should be addressed. It must be written as simple as possible. The point or topic can be the function of equipment, installation of jigs, cleaning method, types of lubrication and methods of inspection etc. It is generally prepared by supervisors or group leaders and sometimes by operators. An OPL is given, to pass on better knowledge, strengthen the understanding for functions of machines and lines and improve knowledge about maintenance defect prevention. The OPL should be given at the Gemba / shop floor / on the machine and when possible in the training center near the shop floor. 

Checking for the defects on line:

I visit the production line and communicate and keep a track with the buy off operators for the recurring defects affecting the FRC/FBO of the stages the top concerns. • Buy-off Overview: The Buy-off is an inspection, rectification and certification operation, which is necessarily done at the end of a group of predetermined stages by the Inspector and/or Production Operator. The Inspector or Production operators should be from a trained group of personnel who have the experience of all the stages of work & understand the procedure & discipline of Buy-off.

The Various Indicators & Terms of Buy-off: There are number of indicators used to monitor the trends in the buy-off stages. These indicators give an early indication of the stability and health of a process. When acted upon proactively, it will ensure higher levels of customer satisfaction. • First Run Capability (FRC): First Run Capability gives the indication of the percentage of Vehicles/Aggregates/Components (Units) bought off, without any rectification, within TACT and gives an early indication of the stability of the process. FRC = No. of units without any Rectification or Rejection X 100

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First Time Buy-off (FBO): First Time Buy-off gives the indication of the percentage of Vehicles/Aggregates/Components which are without any rectification and those which are rectified within TACT. FBO = (No of Units reworked within TACT + FRC Units ) X 100 No. of Total Units Inspected • Defects per 1000: Defects per 1000 gives the indication of the defects encountered at the Buy-off per 1000 Vehicles/Aggregates/Components. Defects per 1000 = Total No. of Defects observed X 1000 No. of Units Inspected

Checking for stages on which defect and root causes of the defects: To find the root cause the stage of fitment or inspection need •

to be monitored minutely. If the defect is manual error /related to design / vendor related is only confirmed after monitoring the stage on production line. • Conducting Trials. Over 15 trials have been conducted: Checking whether the part is O.K. for production or there are any issues in fitment. Checking vehicles with trial parts and ensuring that the vehicle is defect free. These trials are taken for various issues •

Quality improvement: Hexagonal combi-bolt changed to collar loctite

• •

Value engineering: reduce flange on number plate. For ease of assembly: horn mounting bracket. Angle correction.-horn

bolt.

mounting brkt. Angle between drain hole and brkt to be changed from 90 deg to 75 deg. • Work content reduction: Bolero DI wheel arch and mudflap in single piece • Productivity improvement: Assembly of rubber on transmission covers at vendor’s end. • Maintaining data for defect phenomenon: The data of every physical phenomenon is updated monthly this helps the management to monitor the trends of concerns. All the defects are categorized according to the type and their monthly occurrences at R.F.I. are shown in this matrix. This kind of data is very helpful for the management to get a quick idea about which defects are hampering the quality of the products. After monitoring the frequency and trends of the concern the management also gets a review of the concern they have worked upon which helps them to configure their effectiveness to solve the problem and to focus on the major issues. • I have attended seminar on Manufacturing System Design, MSA, APQP, QCRT etc.

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Chapter 4 MANUFACTUR ING SYSTEM DESIGN

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•

Robust MSD is backbone of any manufacturing unit.

•

It has immense capacity to not only assure the Right Quantity with Right Quality at Right Cost, but also, Delivery at Right Time.

•

The concept robust system design not only applies to manufacturing set-up but also to any other set-ups like Software system design, service.

•

It is not a rigid approach but has got lot of flexibility built in it.

We basically view building of strong MSD from 2 angles: A. Preventive approach B. Corrective approach 

Preventive Approach : Various process controls are:

DCP activities: –

Process Flow Chart

–

Process FMEA

–

Control Plan

–

SOPs

–

Buy-off check sheets

–

Poka Yoke

DCP Definition: •

Dynamic Control Planning (DCP) is a process that links quality tools to build robust control plans.

•

Quality, analysis, and planning tools are used, along with team experience, to produce a cohesive system of knowledge. Process controls are developed from this cohesive system of knowledge.

•

DCP is a strategy and a process for building control plans, process performance and predictability improve when the DCP strategy is the planning philosophy.

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DCP Approach: •

It strategically uses elements like flow charts, FMEAs, and Control plans together, rather than separately, in a whole system approach to process planning.

•

DCP also works well in stopping the cycle of “Fire-Fighting” that often hampers existing processes through poor planning.

•

Many successful processes.

•

The DCP Critical Path

•

DCP consists of ten critical path steps

DCP

applications

are

optimization

of

existing

DCP – Process Approach

•

DCP is a Focus on the Process

•

A Process is defined by three elements –

Input

–

Transformation Mechanism

–

Output

–

Everything we do is a process, even simple things like making coffee or driving to work.

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PFC: •

It is schematic representation of Process Flow (Current or Proposed).

•

It is also one of the Focus Element of Advanced Product Quality Planning (APQP).

•

Process Flow Chart must be detailed enough that people outside the Team can use it like a map to walk through the process.

•

It provides a visual representation of a process.

•

It also captures in a standardized format, auxiliary information associated with the various steps of the process.

Constructing the process Flow Documents is the first step USES: – – –

Showing the Process Operation Graphically. Determine what outcomes are desirable from each step. Analyzing sources of variations.

–

Of machines, materials, methods and manpower.

–

From beginning to the end.

–

Helps in analyzing total process than individual steps.

–

Focuses on reducing non-value added activities.

Operation No. : •

Should be numbered consecutively.

•

Should be Multiples of 10.

•

Be careful not to break a process down into too many sub-operations.

Work station no. / Machine No. : •

Mention Machine Make / Work station.

•

Do not mention actual machine no. e.g. Milling M/C No. 2310, Hobbing M/C No. 123 is not expected.

•

Work Station identification will give clarity with what capability product can be delivered.

• In Main Line Assly depicts actual product flow online & Off Line Assly depicts supporting assemblies which can’t be carried out online due to TACT time pressure.

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Type of operation: •

Operation

•

Storage

•

Inspect

•

Move/Transport

•

Delay

•

Operation & Inspection Together

SC/CC: •

SC means significant characteristics which are related to aesthetic look of the vehicle.

•

CC means critical characteristics which are related to government CMVR rules.

Characteristics

Severity

Occurrence

Critical

9 & 10

-

Significant <SC> 5 to 8

5 & Above

Continuous Improvements: •

Process Flow Chart gives an excellent opportunity to look for improvement / weaknesses. •

Benefits of a process flow: –

It can be used as tool in many contexts:

•

Bottleneck analysis.

•

As foundation for remaining process review documents

–

PFMEA

–

Control Plan

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PFMEA  Introduction of PFMEA: 1. Background:

2.

•

FMEA was developed in mid 60’s in U.S.A., by NASA, for Apollo project.

•

It was used in Aeronautical Engineering.

•

Subsequently it was used in Nuclear Engineering.

•

Finally it was applied to Automobile Industry.

•

Now, it is an integral part of many Automobile Manufacturer’s QA system.

What is FMEA?

It can be described as a systematized group of activities intended to: •

Recognize and evaluate the potential failure of a product/process and its effects.

•

Identify actions which could eliminate or reduce the chance of the potential failure.

•

Document the process.

•

It is a technique of reducing or avoiding ‘RISK’.

•

It is an analytical technique utilized by an engineer/team and is a summary of the team’s thoughts (including concerns) as a product or process is developed.

•

This systematic approach parallels and formalizes the mental discipline that an engineer normally goes through in any process.

•

It is “Before-the-event” action and NOT an “After-the-fact” exercise. FMEA is a living document.

FMEA: TYPES •

Concept / System FMEA

•

Design FMEA

•

Process FMEA : PFMEA

•

Machine FMEA: MFMEA

: DFMEA

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Concept FMEA: •

It is used to analyze concepts for systems and sub-systems in the early stages.

•

It focuses on potential failure modes associated with the functions of a concept proposal caused by design decisions that introduce deficiencies.

•

It includes the interaction of multiple systems and the interaction between the elements of a system at concept stage.

•

List of Potential Concept Failures.

•

List of Concept Functions to be included in Design Specifications.

•

List of Design Actions to eliminate the causes of system failure modes or reduce their rate of Occurrence.

•

Recommended changes to System Design Specifications (SDS).

Design FMEA: •

It is used to analyze products before they are released to production.

•

It focuses on potential failure modes of products caused by design deficiencies

Design FMEA: Outputs The outputs of a DFMEA include: •

A list of potential failure modes

•

A list of potential critical and significant characteristics

•

A list of design actions to reduce the severity, eliminate the causes of failure

•

Confirmation of the DVP (Design Verification Plan)

•

Feedback of the design changes

Process FMEA: •

It is used to analyze manufacturing and assembly processes

•

It focuses on potential failure modes caused by manufacturing or assembly process deficiencies

•

Confirms the need for special controls in manufacturing

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Process FMEA: Outputs •

The outputs of a PFMEA include:

•

A list of potential process failure modes

•

A list of confirmed Critical Characteristics

•

A list of confirmed Significant Characteristics

•

List of Recommended Actions for products with Special Characteristics

•

Changes to process sheets and assembly drawings

Need of FMEA: •

To identify potential failure modes which may adversely affect safety or compliance with Govt. regulations

•

To identify potential design deficiencies before releasing to production

•

To identify potential process deficiencies before production begins

•

To identify Critical and/or Significant Characteristics

WHEN FMEA IS INITIATED? •

When new systems, products, and processes are being designed

•

When existing designs or processes are being changed

•

When carry-over designs/processes will be used in new applications or new environments

Define Scope: • The scope establishes the boundary of FMEA Analysis. It defines what is included & excluded based on type of FMEA being developed • Scope needs to be established at the start of the process to assure consistent direction & focus. • The scope of analysis identifies components, assemblies or operations that will be the subject of the FMEA, and equally, those that will be excluded from the analysis. • It would be useful to construct a analysis boundary around the block diagram/process flow chart so that the team members can focus their analysis on elements within the boundary.

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High level Process Map: •

The PFMEA should be consistent with the information in the process flow chart.

•

The scope of the process flow chart should include all manufacturing operations from processing of individual components to assemblies including shipping, receiving, transportation of material, storage, conveyors, labeling, etc.

•

In order to assure continuity, it is highly recommended that the same cross-functional team develop the Process Flow Diagram, PFMEA, and Control Plan.

•

The PFMEA should be consistent with the information in the process flow chart.

•

The scope of the process flow chart should include all manufacturing operations from processing of individual components to assemblies including shipping, receiving, transportation of material, storage, conveyors, labeling, etc.

•

In order to assure continuity, it is highly recommended that the same cross-functional team develop the Process Flow Diagram, PFMEA, and Control Plan.

Severity: •

Severity is an assessment of the seriousness of the effect of the potential failure mode to the customer

•

It applies to the effects only

•

Estimated on a “1 to 10” scale

•

The severity of the effects on the vehicle and ultimate customer will be shown in the Design FMEA for the part

•

Team should have consensus on severity of each effect using the Severity Rating Table

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Severity Evaluation Criteria

Criteria: Severity of Effect This ranking results when a potential failure mode results in a final customer and/or a manufacturing/assembly plant defect. The final customer should always be considered first. If both occur, use the higher of the two severities. (Customer Effect)

Effect

Hazardous without warning

Hazardous with warning

This ranking results when a potential failure mode results in a final customer and/or a manufacturing/assembly plant defect. The final customer should always be considered first. If both occur, use the higher of the two severities. (Manufacturing/Assembly Effect)

Ranking

Very high severity ranking when a potential failure mode affects safe vehicle operation and/or involves noncompliance Or may endanger operator (machine or with government regulation without assembly)without warning. warning

10

Very high severity ranking when a potential failure mode affects safe vehicle operation and/or involves noncompliance Or may endanger operator (machine or with government regulation with warning assembly)with warning. Vehicle/item inoperable (loss of primary function).

Very High Vehicle/item operable but at a reduced level of performance. Customer very dissatisfied.

High

Criteria: Severity of Effect

9

Or 100% of product may have to be scrapped, or vehicle/item repaired in repair department with a repair time greater than one hour. Or product may have to be sorted and a portion (less than 100%) scrapped, or vehicle/item repaired in repair department with a repair time between a half hour and an hour.

Vehicle/item operable but Or a portion (less than 100%) of the product Comfort/Convenience item(s) inoperable. may have to be scrapped with no sorting, or Customer dissatisfied. vehicle/item repaired in repair department with a repair time less than a half hour.

Moderate

8

7

6

Low

Vehicle/item operable but Or 100% of the product may have to be Comfort/Convenience item(s) operable at reworked, or vehicle/item repaired offline but a reduced level of performance does not go to repair department.

5

Very low

Fit and finish/Squeak and Rattle item does not conform. Defect noticed by most customers (greater than 75%).

4

Minor

Fit and finish/Squeak and Rattle item Or a portion (less than 100%) of the product does not conform. Defect noticed by 50% may have to be reworked, with no scrap, online of customers. but out of station.

3

Very Minor

Fit and finish/Squeak and Rattle item Or a portion (less than 100%) of the product does not conform. Noticed by may have to be reworked, with no scrap, online discriminating customers(less than 25%) but in station.

2

No discernible effect

1

No Negligible

Or the product may have to sorted, with no scrap, and a portion (less than 100%) reworked.

Or slight inconvenience to operation or operator, or no effect.

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•

It is how frequently the specific failure cause/mechanism is projected to occur

•

The occurrence ranking number has a meaning rather than a value

•

Estimated on a “1” to “10” scale

•

The failure rate can be based upon historical manufacturing and assembly failure rates experienced with similar parts or process.

PFMEA Occurrance Evaluation Criteria Probability

Likely Failure Rates

Ppk

Ranking

Very High:

>/= 100/thousand pieces

<0.55

Persistent Failures

50/thousand pieces

>/=0.55

9

High:

20/thousand pieces

>/=0.78

8

>/=0.86

7

5 per thousand pieces

>/=0.94

6

2 per thousand pieces

>/=1.00

5

1 per thousand pieces

>/=1.10

4

0.5 per thousand pieces

>/=1.20

3

0.1 per thousand pieces

>/=1.30

2


>/=1.67

1

Frequent Failures Moderate: Occasional Failures

Low: Relatively Few Failures

Remote: Failure is unlikely

10

Classification: • This column is used to classify any special process characteristics (e.g. Critical or Significant) for components, subsystems or systems that may require additional process controls. • Identified in the PFMEA form with the appropriate character or symbol and addressed in the Recommended Actions. –

CC : Severity Rating 9 or 10

SC: Severity Rating 5 to 8, Occ. 5 to 10

Detection:

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•

It is an assessment of the ability of the proposed current design controls to detect the potential cause of the failure mode, or the failure mode before the component, system or subsystem is released for production.

•

When several controls are listed for a particular failure mode, estimate a Detection rating for each control.

•

Enter the best (lowest) rating.

Risk Priority Number (RPN): RPN is the product of severity (S) time’s occurrence (O) time’s detection (D) rankings and a measure of design ‘RISK’ RPN = (S) x (O) x (D) RPN will be between “1” to “1000” Team must undertake efforts to reduce risk through corrective actions; special attention should be given when severity is high The use of RPN threshold is NOT a recommended practice for determining the need of actions.

Example

Item A B

Severity 9 7

Occurrence 2 4

Detection 5 4

RPN 90 112

In the example, if arbitrary threshold of 100 is followed, then action would be required to take on the characteristic B with RPN 112. However the priority should be to work on A with the higher severity of 9, although its RPN is 90 which is lower and below the threshold. Following prioritizing criteria is applicable 1) Severity: 9-10 2) Criticality (S x O) above 36 (6 x 6) 3) RPN: Highest RPN Rating

CONTROL PLAN What is a Control Plan? Study & elimination of defects using QC story & QCRT methodology Nitesh Ranganath Galfade (D-050709)

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•

A summary of the system for controlling,  variation of product characteristics  process characteristics

•

Contract between supplier and customer

•

Summarizes the entire control strategy

Header Information: •

•

•

Prototype : –

Developed for prototypes where majority of characteristics are 100 % inspected or tested

–

Includes a description of measurement/tests that occur during prototype builds

–

Use production process whenever possible

Pre-launch or Pilot : –

Description of measurements/tests before full production

–

Most pre-launch should be under typical production condition

Production : –

Comprehension documentation.

–

Change in Size & Frequency

–

Encompasses high volume production

 Developing Control Methods •

For process control to be effective, a basic understanding of Process Management is essential

•

If capability is poor then first work to solve the problem. Inspect till resolution

•

Team should analyze sources of variation in the process

•

identify dominant factor to suitably decide controls

•

Make failure impossible to improve process robustness

 Sources of Variation •

High turnover of operator

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•

Operator too busy to pay attention

•

Operator forgets sequence

•

Supplier part variation

•

Mixing of parts  Some more Details:

•

In support of control plan, process monitoring instructions should be defined

• Control Plan does not replace the information contained in detailed operator instructions •

Sketches to be attached for better illustration

•

Control Plan is updated as measurement systems & control methods are evaluated & improved

•

Assessment of Control Plan for Quality of Event

•

A checklist for assessment of Control Plan is used •

Prototype, Pre-launch, Production

•

The checklist basically mentions the activities expected to be done during the Control Plan.

•

While performing the assessment, assessor(s) should review each point by posing question, ‘has the expectation been met?’

•

It should be Rated as per the guideline

•

The minimum Overall Score Expected is ‘2’

•

Checklist can be used anytime

•

Benefits of Control Plan •

Provides a thorough evaluation of the product & process

•

Focus resources customer

•

Identifies sources of variation in process which cause variation in product characteristics

on

characteristics

that

are

important

to

 It describes all actions to assure process would be state of control •

Control Plan Provides a structured approach for the design, selection and implementation of value-added control methods for the total system

Operator Process Instructions •

Objective

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–

Operator Process Instruction is prepared to effectively deploy the Control Strategy.

–

Instructions shall include specific information that describes in a step-by-step fashion •

What to do?

•

How to do?

• Instructions must : –

be in line with the Control Strategy ( PFMEA & Control Plan )

–

be manageable and easy to maintain

–

be available at each operation

–

show step by step detail

–

be easy to understand (pictures & diagrams)

–

be controlled (documentation)

–

be understood by all involved - Local Language preferably

Guidelines for Generating Instructions: • Involve Users

•

–

Involve Operators, Auditors, Maintenance Personnel etc

–

User involvement in creation generates good ideas

Use Visual Aids –

•

Pictures, Flowcharts & Diagrams, Samples, Forms, Check-sheets

Use standardized documentation formats

Operator Process Instructions: •

Operator Process Instruction may be in the form of, –

Process sheets

–

Inspection and laboratory test instructions

–

Traveler Cards

–

Test procedures

–

Standard Operating Procedures

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Instructions in SOP should include: –

Part No. & description, Operation No.& description, Cell Name, Machine / Work Station No.& Name, Model Name and SOP document No.

–

Operator’s Procedure and Reaction plan

–

Preventive Maintenance instruction

–

Check Points Before start of operation

–

Tool / Machine setting instructions

–

Effect on next Customer

–

Tool Management instructions

–

Product / Process Parameters specifications

–

Safety Instructions

Effective Deployment of SOP: In addition to documented Instructions •

Perform a skills analysis for each operation

•

Provide adequate training

•

–

Maintain training matrix

–

Schedule training to meet needs identified by skills analysis

–

certify each operator (very significant for operator dominant process)

–

Only trained operators to be allowed to operate

Periodic Audit of SOP using Check list

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Chapter 5 ADVANCED PRODUCT QUALITY PLANNING

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APQP (ADVANCED PRODUCT QUALITY PLANNING) Introduction: APQP Definition: Advanced Product Quality Planning (APQP) is a structured method for defining and executing the actions necessary to ensure a product satisfies the customer. APQP is required of all vehicle, system, subsystem and component manufacturing locations.

Goal: The goal of APQP is to facilitate communication with all persons involved in a programme and ensure that all required steps are completed on time, at acceptable cost and quality levels.

Purpose:

The purpose of this guideline is to establish: • • • • •

Common APQP expectations for all M&M activities. Common APQP process metrics. Common APQP deliverables. A common programme status-reporting format. Lead and Support roles and responsibilities for each APQP Element.

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Approach:

This guideline focuses on 23 key APQP elements. Definitions, expectations, and deliverables for these elements are identified in Section 5.0 APQP Element Description of this guideline. The status for these disciplines is summarized on the APQP Status Report. This guideline provides a management tool for follow-up and timely completion of all 23 APQP Elements.

Applicability:

APQP status reporting is a requirement of all M&M activities and must be applied to the following: • • • • • • • •

New Product launches / relaunch. Changed / modified product launch. Launch of a new manufacturing site. Significant process changes (new facilities/ tooling). High impact suppliers. Carry over issues. Part Submission Warrant (PSW) requirement as per the MQS Mahindra Production Part Approval Process Manual.

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MPDS MILESTONES S I

S IP

SI

STRATEGIC INTENT

SC

STRATEGIC CONFIRMATION

PA

PROGRAMME APPROVAL

R

DR

DESIGN READINESS

D C

DC

DESIGN CONFIRMATION

PC

PROGRAMME CONFIRMATION

PR

PROGRAMME READINESS

PP

PP

PRODUCTION PROVE-OUT

S O

SO

SIGN OFF

LR

LR

LAUNCH READINESS

J1

J1

JOB 1

F S

FS

FINAL STATUS

A

A A A DA

PC

PR

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Generic Process Flow – APQP START

CRITERIA FOR APQP

MANAGEMENT ESTABLISHES CROSS-FUNTIONAL TEAM

INITIATE APQP PROCESS

START APQP REPORTING

MAJOR REVIEW MEETING INCLUDING APQP ASSESSMENT RESULTS

RISK ASSESSMEN T Y/R

Yellow/Red

APQ P STAT US Green

APQP ASSESSMENT GREEN

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The APQP Status Report Purpose The APQP Status Report summaries the status for the 23 APQP elements. The status report facilitates communication between Product Engineering, Manufacturing Engineering and Manufacturing Plants etc. It also provides a dated record that future programmes can reference.

Status Reporting Responsibility For each of the 23 elements, there is a lead responsibility defined. This lead function obtains the necessary input/support from other affected functions and consolidates it into a G/Y/R (Green/Yellow/Red) status (per element) on the APQP status report form.

Reporting Requirements Each Team will be requested by Quality/ Programme Office to submit an APQP status. The Quality/ Programme Office consolidates the APQP status report and submits assessment results for use at all major Programme Reviews/ Gateways. Whenever an element is assessed not Green a Risk Assessment must be submitted to the Quality/ Programme Office.

Ratings and Assessment G Y R Status Green – Yellow – Red (GYR) Status communicates the progress towards the successful completion of an APQP element by the Programme Need Date. The Programme Need Date is the last possible date an element can be completed and not adversely affect quality or timing of the Programme. The “GYR Status “column of the report shows the assessment for each element. Definitions for Green, Yellow, and Red are as follows: Green – “G” ratings are given before the Programme Need Date (PND) to indicate the element will meet the Programme Need Date and will meet all quality expectations. “G” ratings given on the PND indicates that the element is complete and meets all quality expectations (See Section 5 for element expectations / deliverables). Yellow – “Y” ratings are given prior to the Programme Need Date to indicate an element will not meet the PND or quality expectations. To be considered “Y”, a risk assessment and a recovery plan must be in place for the element. “Y” ratings indicate a need for programme management attention. A “Y” rating can only be given to an element prior to the Programme Need Date (PND). Red – “R” ratings are given prior to the Programme Need Date to indicate an element will not meet the Programme Need Date or quality expectations. To be considered “R”, a risk assessment and a recovery plan must be in place for the element. “R” signifies the Programme is at risk and needs immediate management attention. Any element rated “R” at its PND must carry the “R” rating through the remainder of the Programme. Completion of the element after the Programme Need Date does not change the status of the element; the element is late and must stay red. To reflect improvements of a RED Study & elimination of defects using QC story & QCRT methodology Nitesh Ranganath Galfade (D-050709)

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element’s status after the PND, progress to GREEN will be shown by a second entry in brackets.

The 8 Focus Elements: For all 23 elements, quality expectations are defined in this Guideline. Out of the 23 elements, the following 8 elements are considered as Focus Elements: 1. Design FMEA 2. Design Verification Plan 3. Prototype Build Control Plan 4. Manufacturing Process Flow Chart 5. Process FMEA 6. Pre-Launch Control Plan 7. Operator Process Instructions 8. Production Control Plan These elements when completed with Quality and On Time lay the foundation for Programme success.

The 23 APQP Elements 1. Sourcing Decision Definition Sourcing Decision is a formal customer commitment to work on a timely basis with internal and external suppliers on the programme.

2. Customers Input Requirement Definition  The Customer Input Requirements Element is used to initiate the Quality Planning process through identification of design criteria and programme requirements.  Quality Function Deployment, (QFD) is the mechanism to generate the Customer Input Requirements.

3. Design FMEA Definition A Design or Concept FMEA is a systematic approach (used by the design responsible team) which assures that potential design failure modes and associated causes are considered and addressed.

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4. Design Reviews Definitions Design Reviews are regularly scheduled meetings led by the design responsible activity and must include any affected areas, such as, Manufacturing Engineering, Plant personnel etc. The review process includes the following:  A series of verification activities that are more than engineering inspection.  An effective method to prevent problems and misunderstandings.  Provide a mechanism to monitor progress and report to the management (including the review of APQP open issues)

5. Design Verification Plan &Report Definition The Design Verification Plan & Report (DVP&R) is a document listing the engineering evaluations, tests, and reports required to establish a design fit for use in the intended environment and meets the customer driven objectives and the intent with which the product / process was designed. The design verification plan has a correlation with the Customer Input Requirement.

6. Subcontractor APQP Status Definition The Subcontractor APQP Status identifies and reports on the condition of an external Supplier or Subcontractor’s APQP process. It is required of Supplier to cascade APQP requirements to their suppliers or subcontractors and conduct APQP reviews as appropriate. The results of these reviews are summarized on line 6 of the APQP Status Report.

7. Facilities, Tools & Gauges Definition The Facilities, Tools and Gauges element identifies the new, additional, refurbished and relocated resources necessary to manufacture the customer specified product at designated quantity and quality levels.

8. Prototype Build Control Plan Definition Prototype Build Control Plan (PBCP) is a description of the control factors that will be used to manufacture and assemble a prototype build. In the control plan evaluation process, PBCP is the first summary document. This document is necessary to align the responsible activities process steps to both the significant / critical product characteristics and customer targets. 9. Prototype Builds Study & elimination of defects using QC story & QCRT methodology Nitesh Ranganath Galfade (D-050709)

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9A. EP (Engineering Prototype) Definition The Prototype Builds Element entails the manufacture or assembly of components, systems or sub-systems, and assembled vehicles that will be supplied to the customer for builds occurring prior to the Verification Prototype (VP) Build phase.

9B. VP (Verification Prototype) Definition This entails the manufacture or assembly of components, subsystems, systems and assembled vehicles that will be used for verification testing

10. Drawing and Specifications Definition The Drawing and Specifications Element refers to all engineering drawings, CAD data, material specifications and engineering specifications.

11. Teams Feasibility Commitment Definition The Team Feasibility Element determines whether the proposed design can be manufactured within the guidelines. A cross-functional design review team is charged with assessing design feasibility. Once workability is established, the Programme Management Team undertakes the responsibility of following the design review process and reassessing feasibility for any design or part change that may occur during part development.

12. Manufacturing Process Flow Charts Definition The Manufacturing Process Flow Chart is a graphic representation of the current or proposed sequence of manufacturing process flow.

13. Process FMEA Definition A Process FMEA is a systematic approach used by a manufacturing responsible team to assure that potential process related failure modes and their associated causes have been considered and addressed.

14. Measurement System Evaluation Definition Measurement Systems Evaluation assesses the variation of the measurement system and determines whether the measurement system is acceptable for monitoring the process.

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Definition The Pre-Launch Control Plan is a written description of the dimensional measurements and material and functional tests that will occur after prototype build and before full production.

16. Operator Process Instructions Definition Operator Process Instructions describe the details of controls and actions that operating personnel must perform to produce quality products.

17. Packaging Specifications Definition The supplier of a product must ensure that individual packaging for shipment (including interior partitions) is designed and developed. Customer packaging standards should be used wherever available.

18. Production Trial Run Definition The production trial run is a validation of the effectiveness of the manufacturing and assembly processes using production tooling, equipment, environment (including production operators), facilities and cycle times. Output of the Production Trial Run is used for Production Part Approval and Quality Planning Sign-Off.

19. Production Control Plan Definition The Production Control Plan is a written description of the systems for controlling parts and processes during full production.

20. Preliminary Process Capability Study Definition The Preliminary Process Capability Study is a statistical assessment of the ability to produce product within specification.

21. Production Validation Testing Definition Production Validation Testing refers to engineering tests that validate that products made from production tools and processes meet engineering standards.

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Definition Production Part Approval is the documented verification that all customers engineering design requirements are met by the internal or external supplier and the process has the potential to produce to these requirements, where applicable during an actual production run.

23. PSW Part Delivery at Material Required Date (MRD) Definition PSW part delivery at the Material Required Date (MRD) is the final date that fully approved (PSW) material must be received at the customer’s plant to support their Production Trial Runs.

WORK DONE IN APQP: On 19thDecember 2008 new model prototype of Bolero Look-Maxxitruck was to be taken. During production my job was to note various concerns & defects due to design, manufacturing, process etc. may take place on line.Dimensions taken by me online as follows: Sr. no

Distance between

Vehicle Sr.no. 81L57573 (mm)

Vehicle Sr.no. 81L57574 (mm)

1

Cross member & tail-pipe

195

200

2

Tail-pipe & Chassis cross member

170

160

3

Tail-pipe & chassis long member

40

50

4

Mufler rear end & chassis long member

110

105

5

Mufler front end & chassis long member

120

115

6

Mufler joint & chassis long member

160

160

7

Gas expansion rear end & Chassis long member

118

115

8

Gas expansion front end & Chassis long member

90

85

9

Gas expansion joint & Chassis long member

110

105

10

Intermediate pipe & chassis long member

55

50

11

Vertical flange & mufler joint

66

70

12

Mufler front end & vertical flange

30

30

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Chapter 6 QCRT METHODOLO GY

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Purpose •

•

Ensure that Plant controllable top customer concerns are acted upon quickly, permanently and resulted in robust, durable actions. ‘Customer’ in this context, refers to both internal and external customers. Get the entire plant to participate in problem-solving.

Concern resolution Quick response Concern Resolution Team. (QCRT) process drives quality improvement, focused on customer expectations. QCRT is concern resolution system whose goal is to durably enhance our problem solving capability. To increase capability of problem resolution, the following factors must be acted on simultaneously: 1. Avoid problems recurring 2. Increase the speed of resolution without sacrificing the quality of resolution. 3. The speed of resolution is required to allow another problem to be dealt with.

To ensure the quality of problem processing, it is necessary to: a- Systematically apply the P-D-C-A cycle by SDCA management (Refer Annexure 1 & 2) of WSS, use of the QC Story technique, and rigorous application of the QCRT process. b- Limit the number of problems assigned to each person, to ensure better S-D-C-A processing quality. c- Reinforce the skills of the persons involved in problem processing, to ensure the correct actions are implemented on the true causes of problems and make the best use of the quality tools at our disposal. d- Assign problems at the correct level of responsibility, so that the problem owner (person responsible for the problem) can effectively work rapidly and correctly on the root causes. e- Continuously evaluate the effectiveness of problem processing to identify the causes of impediments and difficulties.

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The QCRT approach is based on the following principles:

•

The activity must be performed each day at a fixed time and be one of the priority activities, managed by top-level management.

•

The presence of all managers required to deal with problems (the production, local engineering, quality, supplier quality, maintenance, logistics, etc. departments), with the roles of each clearly identified and an attendance register / sheet kept

•

A limited number of problems revealed by key indicators for the areas concerned

•

Problem processing by a single manager relying on the MAPS tools, the QC Story technique and SDCA management of WSS/DCP

•

Immediate protection of the customer managed via use of the corresponding tools (Poka Yoke, self-check, etc.)

•

A standard chronology that is the same each day, structured in 4 phases: Quality results, problem of the day, problem from the previous day and closure of a problem.

•

The closure of problems, once the objectives have been achieved over at least one month and a check that the solutions have been standardized.

•

The effectiveness of the sessions is measured, displayed and continuously improved.

•

The involvement of management in assisting the members of the meeting to improve their problem-solving skills.

•

A capitalization (on information) process, that is robust and that can be accessed by everyone.

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Chapter 7 CONCERN RESOLUTION PROCESS (QC STORY)

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Concern Resolution Process Purpose of Concern Resolution Process •

To establish structured approach for – Identify and eliminate causes of non-conformance. – Planning of correction and necessary corrective actions. – Implementation, monitoring of actions planned effectiveness.

to

improve

FLOW CHART (Concern Resolution Process)

Conformity Analysis (L0)

Phase I

Concern Resolve d

Yes

NO QC Story initiated

Phase II

Concern Resolve d

Yes

NO

Phase III

Design related concerns Escalated to PVT

Concern Closed

Phase I – L0 Analysis

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•

Conformity Analysis – (L0 Analysis) – Conformity Analysis is carried out for defects identified at RFI, NOVAC/ Ad. NOVA-C, PDI, CCAS, GD etc. – If cause(s) for the problem is not identified in Conformity Analysis, then QC Story to be initiated – Lead Responsibility of Analysis : Cell Leader

QC Story Introduction to QC Story Definition "QC STORY" is a problem-solving technique based on the examination of facts and data, with no speculation, intended for problems caused by a number of issues. QC story: a problem-solving method, QC Story is not only applicable to quality problems, but also productivity, cost, logistic, power, safety, etc., problems. QC story: A means of communication QC story is both a problem-solving tool and also often a communication tool. It is rarely the case that the problem to be dealt with does not affect colleagues or need to be communicated at company level (capitalization). QC story has been introduced in Europe, notably in Nissan's Sunderland (UK) plant in 1992, then in the Barcelona plant. Since QC Story was implemented, Nissan has evolved, moving from an 11-step process to a more concise 9-step process.

The 9-step QC Story process

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P 1- Select the subject (theme/issue) 2- Justify the choice 3- Understand the current situation

A

4- Select targets

9- Summarize and plan action

D

P

future

A

5- Analyze

D

8- Standardize

C

6- Implement corrective measures

C

7- Confirm the effects

QC Story Steps • • • • • • • • •

Step1: Select the Theme Step 2: Justify the choice Step 3: Understand the current situation Step 4: Select Targets Step 5: Analysis (Level 1 Analysis) Step 6: Implement corrective measures Step 7: Confirm the Effects Step 8: Standardize Step 9: Summarize & Plan future actions

•

Theme: This section of the Q.C. Story contains one simple sentence, the Issue Statement. An Issue Statement contains three elements: Direction, Measure, Reference to a process, product, or service For example: "Reduce (direction) the percentage of contracts that are returned for rewrite (measure) in the XYZ Contract Department (reference)."

•

Step 1) Select the theme:

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E.g. To eliminate the defect of wrinkles of moulded roof from 16 per month (RFI) to zero.

Step 2) Justify the choice: In this section we explain why we are working on this issue. It is easy to say "customer satisfaction." The question that needs to be addressed here is "How do we know that this is the most important thing to work on" to improve customer satisfaction?

2. a Immediate Containment Action To ensure that customer is protected immediately. It can include containment action and immediate action throughout the supply chain. Some times this step is not applicable.

Step 3) Understand the current situation: Observation of process: Results of process walk through / any non adherence to standard practice or specifications, add process flow chart if required. Add details like: Time to time, location to location, person to person, stream to stream differences as applicable. Use of Sketches, photos, stratification, run chart, concentration diagram, histogram, control chart etc as applicable. Several things need to be explained for the reader to understand the Initial Status.

Step 4) Select Target: Identify the target. A target is a number indicating the level of improvement to be achieved.

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Present Level :

----------------------------------------------------------Based on average data of last --- months

Target:

---------------------------------------------------------Based on average data of last --- months

Pick up data

 

Wk 38 Analysis & 1st trail.

 

wk40  

Again pick up data.

wk42 Analysis

wk44

2nd trail

wk46  

4th trail

wk48

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Step 5) Analysis: 5.1 Identify possible causes: Use following formats -

Cause & Effect Diagram To identify root cause use Why - Why Analysis (MQS/MAPS/F05)

- Level 1 Analysis report: to be used to document all observations, trial results, inspection record, visuals, sketches, part conformity, Fixture inspection/ Calibration details etc.

SOS not available

Man

Method

SOS for the entire fitment not available. Operator not fixed

Holes on body shifted.

Holes not match with body Mould not o.k.

Torque of battery operated gun not o.k.

Foam gets collapse

Material

Calibration not done.

Machine

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WHY - WHY Analysis

&

Report No.

:

td.

Equipment name

:

Date/Time of B/d or Defect Incidence

:

Phenomenon:

Wh

TEST OF HYPOTHESIS Confirm the probable cause: Cause No

Probable Testing and Observations Cause

Conclusion

N

G

Cause

Cause

N

G

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Data are collected to determine and verify which of the several possible causes the cause of the problem is, in fact. There are several analytical tools to help with this effort: Check sheets, histograms, or scatter diagrams are very useful. The story should include the time period over which the data were collected. We sometimes run small-scale experiments to collect Data about causes or to verify that we have found the actual causes. When the results from these experiments show that our theories are correct, we can include them in this section of the story.

6. Implement the corrective measures 6.1 Actions Decided

Root Cause

Action Plan Target Date

Resp.

Status

Step 6) Implement Corrective Measures: -

-

-

Consider various probable actions Ensure that probable action selected does not create side effects Before implementation, decide on the role of each member and a schedule. Assign each corrective action a priority and stick to it. Involve the operators. Do things yourself, the approach will be all the more concrete! More than half of the corrective actions will require changes to be made: tests and checks are extremely important when implementing corrective actions. Confirm the effect using the same method and same observer. The use of color, limits, graphics, and instructions at the place where the corrective measure is to be applied are effective means of drawing attention to it. Share the results with all interested parties!

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Step 7) Confirm the results & effects: 7.1 Verify Results: -

Compare with the initial conditions (step 3) using the data (charts). Effects must be explained with respect to the direct effect, indirect effect (repercussions), or non-material effect aspects.

7.2 Full Scale Implementation plan: -

The situation before and after the corrective action must be shown and the same charts used as in step 4.

7.3 Tangible & Intangible benefits: -

If the effects can be converted into gains (financial), this is preferable e.g. Return on investment, annualized savings In as far as possible, the effect of each action on the final result must be shown (by numbering them).

Step 8) Standardize: 8.1 Updation of documents: -

Revise or establish the working "standard". Review cycle time, standard stocks, standard machine conditions, etc. Visual tools are highly effective in standardization. Update all the relevant documents like Drawings/specifications, Process Sheets, PFC, PFMEA, Control plan, SOP or SOS, Check list etc, & mention the reference of the same.

8.2 Training: -

If the problem stems from the operating procedure, train the operator on the new standard Train people on new/modified SOP Train people to modify / develop SOS

8.3 Additional Audit / Check -

Check the quality level and how the operator functions with the new method/procedure for at least two weeks. Carry out additional audit/check to ensure adherence to the new system & monitoring results achieved.

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Standardization: Here we explain the steps that were taken to ensure that the implemented solution will remain in effect. We want to prevent the process from reverting to its previous state so we can continue to hold the gains achieved through the process improvement. Step 9) Summarize and future action plans: 9.1 Conclusion -

Once target has been achieved, progress and results are reported to management. Future plans are drawn for causes that cannot be currently resolved. If concern is not resolved & product design change is necessary then it is to be escalated to PVT/PDT/PET for PHASE III actions.

9.1 Horizontal deployment -

Check the possibility of extending the actions to similar product or process.

9.2 Lessons learnt -

Summarize the learning from the project.

The QC STORY done by me: 1. Bonnet 2. Fendor 3. Cargo

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Chapter 8 A Project on: Eliminating the defect loss due to Brake fluid level indicator Wire terminal backout

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Concern Resolution Apart from the daily activities, solving the defects in RFI vehicles was given primary importance, as the vehicles handed over for RFI were a sample of the population which is going to the customer and must have ZERO defects. As stated in the quality PADTA the defect per vehicle in RFI was on a rise and needed to be controlled. Also high severity defects which hampered Mahindra‘s reputation required special attention.

RFI

Defect /vehicl e

No. of zero defect veh.

% of Zero defec t Vehic les

Sev

=>5 F09 Tar F09 Act Apr Ma y Jun Jul Au g Sep t Oct No v Dec

1.40

All

20.00

0.120

1.37

845

21.76

1.50

107

23.57

0.101 2 0.123

1.47

118

22.14

1.38 1.41

84 132

1.35

S Sev Sev e v 10

9

Sev

Se v

Sev

7

6

5

10

27

8

% Redn. Over F-08

3.2 20.6 2 6 4 22

0

6.6

4.1

9.1

0

8

5

17

0.139

0

8

7

25

7

27

24.63 25.73

0.117 0.084

0 0

3 6

4 5

6 7

1 3

26 23

97

20.29

0.096

0

13

3

8

4

27

1.36

110

22.77

0.091

0

7

3

6

4

24

1.29

115

23.37

0.075

0

10

8

4

4

17

1.24

58

16.91

0.076

0

3

2

7

2

12

1.19

24

22.85

0.105

0

1

0

2

0

8

In my training period I was taught various techniques to solve defects. I was also assigned project to reduce defects with the guidance of the QA module managers and other related officials. High severity defect

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In the further part of the report some of the invaluable quality tools and problem solving methodologies which were put to use to solve high severity and high frequency low severity defects will be manifested:

Overview All models in Mahindra have hydraulic brakes .The brake fluid reservoir is situated over the brake booster .There is an alert mechanism to indicate the brake fluid level reduction in the brake fluid reservoir. A brake fluid level indicator bulb is provided on the dashboard which will glow as soon as the brake oil reaches to the minimum desired level. As the level of oil reduces the float comes in contact with the sensor and the driver receives a warning light that indicates brake fluid is either leaking or less than desired and needs to be filled. As the brake fluid reservoir is under the hood, the sensor and the indicator bulb wiring are connected with plastic couplers (male and female sockets).

Problem: The metallic wire terminal have positive locking in the plastic socket .If the locking is disturbed or poor the wire terminal comes out of the socket and the circuit is broken. And the circuit doesn’t serve the purpose.

Brake fluid reservoir Sensor

Brake booster

Terminal backout

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Severity: According to the FMEA severity ranking table this concern is given severity 9 as it risks customer safety.

Effects of the concern:

Wire terminal backout

Circuit cannot be completed No warning indicator even if the brake fluid in reservoir is empty No prior warning before brake failure

May cause accident /customer safety endangered

Problem prioritization: Problem was prioritized due to the following reasons:  It was a high frequency and high severity concern as shown in trend.  It was a serious field concern.  Customer safety endangered.  It was recognized as a vital high severity concern by pareto as stated in the graph below.  It increased the rework.  It was a reason for an increase n R.F.I Defects per vehicle score. As well as the severity concerns per vehicle score.

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Concern Resolution Technique: Step 1: L0 / conformity analysis to confirm there is no error in process at our end. Output: 1.The process and key points for the fitment of body wiring was not defined. 2.The wire terminal and socket may get damaged during fitment process if pulled haphazardly. (CORRECT PROCESS) 3.S.O.S. for the process to be defined and implemented.

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Actions based on output: S.O.S. for the process to be defined and implemented. Step 2: L 1 analysis to find the root cause a.Terminal was not locked in one of the cases observed in the past (Terminals not locked at vendor's end) b.Uneven terminal length observed in one case before. c. To check whether a design change required. Output: 200 % inspection with marking started for every socket at vendor end to assuare that only and only OK parts are delivered to Mahindra and Mahindra. Hole dimension on body was relatively less in CL , CDR and Bolero FB models was brought in the notice of QCRT. Actions based on output: It was decided if the problem doesn’t get solved after taking the actions stated above then design issue to be tken in considration.

Effectiveness graph:

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My role in the project: •

Collecting data for concern prioritization of high severity concerns and making a Pareto diagram to focus on the vital few concerns.

•

Study of the positive locking of terminal and root cause analysis of each case observed at RFI or Buy off stage.

•

Preparation of the L0 and L1 analysis on behalf of the problem manager.

•

Audits of body wiring for poor insertion of wire terminal in as received condition, to ensure that all material is received in OK condition and gets damaged in-house.

•

Making regular observations at the stage of assembly of body wiring.

•

Spotting the difference in the same operation of wiring assembly done by a skilled operator and a new ITI trainee.

•

Making a SOS Standard Operating Sheet with the help of skilled operator and the concerned officers and implementing it.

•

Monitoring the effectiveness of implementing the SOS and vendor improvements through various quality indicators.

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Chapter 9 A Project on: Eliminating the defect loss due to Clutch fluid Study & elimination of defects using QC story & QCRT methodology Nitesh Ranganath Galfade (D-050709)

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leakage through joint at reservoir

Overview: The clutch fluid filter is assembled at front side of body shell. This stage is categorized as ‘Z’ stage, i.e. zero defect stage, because these all parts are related to safety aspects & as per the government regulation. So no defects should occur at this stage during assembly. The part shown in fig. is called clutch fluid filter. It consists of flask which is used to holds the clutch oil. The oil is supplied to clutch via Bundy tube. This tube is fastening by nut which is to be tightening by defined range of torque. The torque range decides for this assembly is 12-14 NM. If this torque is not attained then it might cause leakage of clutch oil. Which might affect the proper functioning of clutch and chances of accidents are increase.

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Leaking joint

Clutch fluid reservoir

Clutch fluid filter

Clutch Bundy tube

Severity: According to the FMEA severity ranking table this concern is given severity 8 as it risks customer safety. PROBLEM PRIORITIZATION: Problem was prioritized due to the following reasons: This stage is categorized as ‘Z’ stage, i.e. zero defect stage, because all parts are related to safety aspects. So no defects should occur at this stage during assembly.  Any defect in ‘Z’ stage should be immediately zeroed. It increased the rework.  It was a reason for an increase n R.F.I Defects per vehicle score. As well as the severity concerns per vehicle score. 



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Analysis Summary: Concern resolution: Step 1:L0 analysis Output of analysis: Leakage due to joint not tightened at the specified torque. Actions taken based on output: OPL to be given to the operator. The root causes analysis for loose fitment to be initiated. Step 2: Cause & Effect diagram and WHY-WHY analysis. Output of analysis: Root cause found-NO Pokayoke. Actions taken based on output: Pokayoke to be installed on the stage. Step 3: Measuring effectiveness.

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EFFECT

VJTI CAUSE AND EFFECT DIAGRAM CAUSES MAN S.O.P not followed.

Hardness of threaded end of clutch Bundy tube less

Disciplinary issue

Joint not torqued

CLUTCH FLUID LEAKAGE JOINT LOOSE (Loose)

Slave cylinder female end hardness less

Lack of knowledge

Torque wrench setting gets disturbed.

No POKA YOKE

DESIGN

MATERIAL

Teflon tape not in use

Torque setting not done.

Relaxation of joint.

Torque wrench poor click sensation after torque application

MACHINE

METHOD

Study & elimination of defects using QC story & QCRT methodology Nitesh Ranganath Galfade (D-050709)

ENVIRONMENT

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Classification

THEME

TPM ONE POINT

Brake fluid leakage joint RFI - Se

Basic Improve Knowledge ent case

A: SITUATION BEF

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POKA YOKE: Poka-yoke is a quality assurance technique developed by Japanese manufacturing engineer Shigeo Shingo. The aim of poka-yoke is to eliminate defects in a product by preventing or correcting mistakes as early as possible. Poka-yoke has been used most frequently in manufacturing environments. Poka-yoke (pronounced "POH-kah YOH-kay") was invented by Shigeo Shingo in the 1960s. The term "poka-yoke" comes from the Japanese words "poka" (inadvertent mistake) and "yoke" (prevent). The essential idea of poka-yoke is to design your process so that mistakes are impossible or at least easily detected and corrected.

How to use Poka Yoke? 1. Identify the operation or process that needs to be mistake proofed (target areas where there are high numbers of errors or where even single errors are very costly). 2. Use the 5 Whys or cause and effect analysis to get to the root of the problem. 3. Decide whether to use a shut-out or attention type method (there may be technical or financial reasons why you have to go for the latter) to tackle the problem.

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4. Decide whether a contact, constant number or sequence method is best (this will hinge on the nature and purpose of the activities). 5. Design an appropriate poka yoke. 6. Test it to see if it works (try to avoid large expense before you have completed this step - use mock ups or make-do's). 7. Once you have a working method then ensure you have tools/checklists/software, etc for it to work consistently and correctly.

the

right

8. Train everyone to use it. 9. After it has been in operation for a while (the time period will depend on the frequency of the activity) review performance to ensure errors have been eliminated. Take whatever steps are needed to improve on what you have done.

Need of Poka-yoke in Body trim cell In body trim cell many parts fitted are critical as per severity point of view. This severity points are given at RFI cell. Decision : After analyze this problem it is decided that apply the concept of poka-yoke at suspended pedal stage. To fulfill the requirement to eliminate this defect of oil leakage, the poka-yoke should be design in such a way so that the body shell should not proceed to further stage if the joint is under torque. It allows further movement only after correcting the torque.

The concept and working of poka-yoke is discussed below.

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CONCEPT OF POKA-YOKE

Fig. 1

Fig. 2

CONCEPT : As shown in figure to apply this concept some equipments are required which are as follows - Wheel sensor - Wheel lock - Torque sensor - Torque wrench - Alarm Now initially the device which is used to tightening the nut was ‘Mechanical torque wrench’. It is to be replaced by ‘Electronic cum mechanical torque wrench’. It is advance version of earlier torque wrench which works on principle of radio frequency. A sensor is providing with this tool which detects the initially set torque is applied to tighten the nut or not. It also has ratchet mechanism same as earlier tool but with electronic sensor for detection, this sensor detects a torque and send signal to torque sensing device by radio frequency. This signal is then forward to the operator by using visual lightening, which is GREEN in colour. If set torque is applied then green light is turn ON. DEVICES

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Other POKAYOKE components Before

After

Mechanical Wheel sensor cum Electronic torque wrench

Mechanical torquedevice wrench Torque sensing and Alarm

Now there is another sensor is provided on the track, which detects the wheels of trolleys. It is combined with torque sensing device through electronic circuit. A trolley lock is also provided on the track to restrict the further movement of trolley; this lock is also combined with electronic circuit and it activates while torque is not done. Actual working of these devices is explained in simplified manner as shown in following table

SR. NO.

TORQUE

1 s t wheel pass

2 n d wheel pass

remark

1.

Done

allow

allow

OK

2.

Done

allow

allow

OK

3.

Not Done

allow

Not allow

Not OK, alarm starts ringing & lock is activated

4.

Done

-

allow

OK

5.

Done

allow

allow

OK

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Case 1, 2 & 5

Case 3

Case 4

Explanation As in first case if torque is done then trolley can move to further stage without any restriction, in this case torque sensing device sense that required torque has been applied and it transferred the OK signals to wheel sensor. Then wheel sensor sense the first and second wheel of the trolley. This sequence is continues till set torque is apply. But as in case three, if set torque is not applied then torque sensing device transferred the NOT OK signal to wheel sensor. In this case when wheel sensor is sense the first wheel then it also transferred the NOT OK signal to not only alarm but also to track lock simultaneously. So that trolley cannot able to move further. To remove this restriction the set torque should apply then only the track lock is deactivate.

Conclusion

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This concept was partially implemented, implementation of trolley lock is remaining, after only partial implementation of this concept no defects were found at final inspection. And it is expected that there should not occur any defects in future. Our set target is of zero defects as shown:

My role in the project: •

Collecting data for concern prioritization of high severity concerns and

making a Pareto diagram to focus on the vital few concerns. •

Doing the primary root cause analysis that the leakage occurs due to less torque applied by studying all the vehicles in the yard having such kind of leakage. Worked in a team of Central QA officer and operator.

•

Preparation of the L0 and L1 analysis on behalf of the problem manager.

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•

Monitoring the effectiveness of implementing the SOS and vendor

improvements through various quality indicators.

•

The study and follow up of the new POKAYOKE implemented for eliminating the defect.

Chapter 10 Study & elimination of defects using QC story & QCRT methodology Nitesh Ranganath Galfade (D-050709)

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A Project on: Reduction of defect loss due to Diesel leakage from fuel tank bottom banjo joint

Overview: The diesel is stored in the fuel tank .It is transferred to the fuel filter and then to the engine. The fuel flows through a fuel pipe.

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Fuel

Copper Eye end of fuel main

Banjo Fuel main

PROBLEM PRIORITIZATION: On the basis of decision matrix

Total

Rework Time (Cost)

Interval (frequency)

Severity

QCRT LEVEL

F.M.E.A. Severity

Source

Concern

Sr. No.

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1 2 3

DIESEL LEAKAGE WRONG PART USED POOR PICK-UP

FUEL TANK BOTTOM BANJO BRAKE PIPE ENGINE

RFI RFI RFI

7 6 6

3 1 3

6 6 6

2 1 1

9 9 6

10 8 54 36

4

PAINT TOUCH UP FORGOTTEN

CARGO SIDE PANEL

RFI

4

2

3

6

1

18

5

MISMATCH

T/G TOP WITH CARGO

RFI

3

3

3

1

9

Severity

9

Interval (frequency)

>15

10
>=20 min

15min< 0m

Rework Time (Cost)

6

Analysis: Concern resolution technique: Step 1: Conformity Analysis Output of Analysis: All the current process parameters in chassis cell were followed. Action based on analysis: Immediate protection taken:

containment actions

for

customer

Daily yard checks.

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Torque increased from mean value (23 lbft) to (27 lbft) upper limit of the specification. Step 2: L 1 analysis and cause and effect analysis.

Output of Analysis and actions: Sr. No. 1

2

3

4

5

6

Probable Cause Thicker washer at M/S Ehara for leakage test Copper washer hardness not as per specification Existing torque spec. not sufficient to stop seepage Dent, damages on copper washers Taper/uneven fuel pipe eye end Work hardness value of copper washer

Testing & Observations In-house test conducted & no air bubbles found when the washers were replaced by thicker ones used at vendor's end. Hardness checked in our lab & found O.K.(Below 50 VPN)Subodh Sharma Torque value increased to 27lb-ft from 23 lb.ft.from 17/11/08. Leakage was observed on 3 vehicles Segregation done & few washers found with dents/damages/deformation.

90 microns difference observed. Values observed between 67 to 90

Actions planned Same washers(Pt. No.0050332) to be used for leakage test at M/S Ehara

Root cause not valid Matter to be referred to Mr. Rahalkar for L2 analysis Matter to be taken up with vendor Matter to be again taken up with M/S Imperial Matter to be referred to Mr. Rahalkar for L2 analysis

Step 3: QC story and monitoring effectiveness.

My role in the project: Collecting data for concern prioritization of high severity concerns and making a Decision matrix. Preparation of the L0 and L1 analysis on behalf of the problem manager. In depth analysis of each case observed during yardcheck to reach at root causes. This included: YARDCHECK: Manually checking all the CL/CDR models for diesel leakage or seepage and recording the results.

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Method: The joint was wiped clean with clean and dry clothes. Then the engine was kept at idling condition for 30 mins. After 15 mins the joint was wiped by a tissue paper which immediately showed stain marks. Using a tissue paper was helpful in detecting exactly the 2 contact surfaces out of the 8 from which the fuel seeps. Taking residual readings of the joint to ensure that the tool provided is used as per the specified procedure. Opening the leaking joint to study the copper washer profile and to verify whether there is a dent or a pathway on any of the contacting surface. Replacing the suspected component (E.g. Washers, bolt, fuel line, fuel tank) with a fresh component To confirm that there is no leakage or seepage after replacing the suspected part to ensure the non conformity in the suspected part. Checking the dimension of suspected parts.5 fuel tank adapters checked for surface flatness and perpendicularity with slip gauges and bubble test. •

Copper washers checked as per the drawing with electronic vernier caliper.

PART

PARAMETER TO BE MEASURED

INSTRUMENTS USED /TESTS CONDUCTED

Fuel main flow joint Copper washers

Leakage Thickness I .D. & O.D. SURFACE

Bubbles test Vernier caliper /Micrometer Vernier caliper Visual inspection with a

Internal thread axis perpendicularity.

Slip gauges of various thickness, master male adapter specially designed by vendor

Surface taper, Surface abnormality

Dial gauge, Micrometer

Fuel tank welded adapter plug

Eye end of fuel pipe

Monitoring the effectiveness of each and every implemented action.

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Chapter 11 A Project on: REDUCTION OF SCRATCHES ON VEHICLE

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Concern Resolution Apart from the daily activities, solving the defects in RFI vehicles was given primary importance, as the vehicles handed over for RFI were a sample of the population which is going to the customer and must have ZERO defects. As stated in the quality PADTA the defect per vehicle in RFI was on a rise and needed to be controlled. Also high severity defects which hampered Mahindra‘s reputation required special attention. In my training period I was taught various techniques to solve defects. I was also assigned project to reduce defects with the guidance of the QA module managers and other related officials. In the further part of the report some of the invaluable quality tools and problem solving methodologies which were put to use will be manifested.

OVERVIEW: A break in the surface of a thing made by scratching, or by rubbing with anything pointed or rough; a slight wound, mark, furrow, or incision is identified as a scratch.

EFFECTS ON CUSTOMER: •

Scratches play an important role in body aesthetics of the vehicle.

•

Decreases the strength of the effected part and make it prone to rusting.

•

Customer dissatisfaction.

Concern prioritization: As you can see below the contribution of scratches has increased suddenly in August. So, there was need to find the root cause for the increase in scratches at RFI audits in detail to reduce the defect per vehicle.

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Figure 1 Contribution of scratches in total defect per vehicle

1400 1200

120 1171 92

1000

97

100

99

80

80

800

66 565

600

100

60

538

40

400 171

200

110

20 34 OTHER PU/ SHORTAGE PROBLEM

PROCESS DEFECTS

PVT / DESIGN RELATED DEFECTS

VENDOR DEFECTS

MANUAL DEFECTS

0 SCRATCHES

0

Figure 2 PARETO TABLE (RFI DATA APRIL-SEPTEMBER '08 )

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ANALYSIS: SCRATCHES ON BONNET: Understanding the situation: 1) PROCESS FLOW CHART PROCESS FLOW CHART FOR IDENTIFICATION OF SCRATCHES Process flow chart for identification of scratches at various stages.

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Concentration Diagram for scratches on bonnet:

BONNET- BOLERO LOOKB O N E T - M A X

4

5

2 BONET-CL-CDR

5 2

3

2

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CAUSE AN EFFECT Runner slips while tightening the bolt

Scratch during on All the probable root causes were investigated andloading the results are shown in the table below: trolley and Conformation of root Concern Part Root causes Photos/Diagram trolley cause movement Excess bonnets kept CONFIRMATION OF PROBABLE CAUSES:

Scratches

Bonnet

on floor near accessory unloading stage.

Scratch on BONNET Study & elimination of defects using QC story & QCRT methodology Nitesh Ranganath Galfade (D-050709)

Valid

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Scratches

Bonnet

Painted surface getting scratches due to rods projecting out of an air circulator.

Scratches

Bonnet

Bonnets projecting out of the trolleys.

Scratches

Bonnet

storage in paint shop

Scratches

Bonnet

part movement in bonnet subassembly

Valid

Scratches

Bonnet

worn out trolley's protective coatings

Valid

Bonnet

grill is fallen in the conveyor line which strikes the bonnet in movement

Valid

Scratches

Study & elimination of defects using QC story & QCRT methodology Nitesh Ranganath Galfade (D-050709)

Valid

Valid

Valid

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Corrective Measures: SR.N O.

1

2

3

4

ROOT CAUSE

ACTION PLAN

TARGET DATE

RESPONSIBILIT Y

STATU S

Mr. Panda Priya

Closed

Scratches at receiving stage from paint shop

Proper storage system like trolleys or racks to be used in paint shop

Unfavorable trolley conditions. 1) Rusty trolleys. 2) Teflon coating worn out. 3) Hardware kept in trolleys.

Regular maintenance to be ensured and proper cleaning to be done.

Scratch during loading on trolley at accessory unloading stage and trolley movement

Excess bonnet not to be kept on floor and operator to be made aware about proper trolley movement

22.10.08

Mr. P.D.Kulkarni

Closed

Incorrect Handling at bonnet subassembly

Movement of trolleys for subassembly should be according to layout and bonnet catch to be kept at designed location when changing the model

20.10.08

Mr. P.D.Kulkarni

Closed

24.10.08

14.10.08

Mr. Kaustubh Naik

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Closed

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Also Painters at touch-up are given training by changing the process i.e. after the vehicle enters the touch-up cell from shower testing shed, they are dried & cleaned using cloth to identify the scratches easily. For cleaning the vehicles workers are deployed.

Conformation of Results: Below are the numbers of scratches on bonnet observed in RFI audit after implementing the corrective actions step by step.

14 20-Oct Week 1 Standardization:

10 3-Nov

•

After the implementation of corrective measures trolleys audits are done by QA inspectors daily.

•

Daily trolleys are cleaned by maintenance workers.

•

Operator training is given for movement of trolleys as per model on assembly line and is checked by line officers.

Week 3

n u th a c fs ro e b m

Horizontal deployment: Fender unloading at the accessory unloading stage. Conclusion & Lessons Learned:

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10-

Wee

VJTI

After monitoring for more than 7 weeks we have achieved the required results i.e. reduction of scratches on bonnet from 14 to 0. During this QC story we have learnt various analysis techniques such as: Pareto analysis, Using QC story as a defect solving techniques, Data collection for detection of root causes.

ABBREVATIONS

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