53218-mt----reliability Engineering And Maintenance Management

Code No: 53218/MT

NR

M.Tech. – II Semester Regular Examinations, September, 2008 RELIABILITY ENGINEERING AND MAINTENANCE MANAGEMENT (Industrial Engineering & Management) Time: 3hours

1.a) b)

Max. Marks:60

Answer any FIVE questions All questions carry equal marks --Discuss the important of reliability. Prove that the hazard model of a system having m components in parallel and each component with a constant failure rate can be approximated to a Weibull model.

2.

Calculate the system reliability for the units connected as shown in Figure-1.

3.a)

Repair will improve the system reliability if it has redundancy. Comment. Explain the functions of reliability in an organization.

b) 4.

Explain the following terms: (i) Maintainability (ii) Mean time to repair (iii) Frequency of failures (iv) Availability. Contd...2.,

Code No: 53218/MT

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5.

An air compressor has to be so designed that its minimum reliability value is 0.90 for an operation time of 1000 hours. The minimum availability value over the same period has to be 0.99. Estimate the time to failure and the mean repair time. Assume constant hazard for failure and repair.

6.a) b)

Discuss in detail the various types of maintenance. What are the policies of maintenance?

7.a) b)

Discuss the application of MIS in maintenance. A company operates three machines with one spare machine available. There are two maintenance technicians (that is repair channels). Each machine fails at a constant rate of twice per week. The mean time to repair is one and two thirds days. Assuming a five day work week, determine the percentage of operating machines and the average down time.

8.

Write notes (i) (ii) (iii) (iv) (v) (vi)

on any FOUR of the following: Standardization Maintenance planning Cost model in machine System reliability Operational availability Benefits of maintenance. &_&_&_&