Marine Fuild Power

Marine Fluid Power Application

Ship Hull Machineries Deck machineries Steering gear Steering thrust device Stabilizing device

Objective • Learning Objective: Know the basic design features and functions of various marine auxiliary machinery • Specific Objectives: • Recognize the various names and locations of auxiliary machinery found on board • Sketch a typical hydraulic system • Describe the basic operation of the machinery • Identify the main parts of the machinery • Sketch and label the main parts

Introduction •

Hull machinery= deck machinery -> independent power equipment drive not related to machinery space and propulsion.

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Steering gears Anchor windlass, Winches (cargo, topping, vang, mooring, accommodation, ladder, boat winches) Cranes, Captains, elevators, dumbwaiters, conveyor, Escalators, bow thruster Active fins stabilizer

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Introduction • Design follows standards machine design which are adapted for marine environment and ship board requirement. • Design of hull machineries required cooperation from marine engineer and naval architecture. Types of drive • Steam- minimum fire hazard, rugged and simple Backdrop insulation • Electric • Hydraulic

Drive - Steam • Simple , rug, easy to maintain • Minimum fire hazardno sparking

• Steam main Insulation • Automation • Control reliability

Drive - Electrical • DC is preferredmultiple motor speeds

• Residual power dissipation through rheostat • Saving for use of ACrequired power electronics system

Open Loop System •The system takes oil from the tank and pumps it into the hydraulic motor. •A control valve is positioned in parallel with the motor->When it is open, the motor is stationary; when it is throttled or closed the motor will operate.

Open Loop System •The exhaust oil returns to the tank •Commonly used in low pressure system •Simple in design as well as reliable.

Open Loop System

Closed Loop System •The exhaust oil does not go back to the oil tank- Hence closed system. •Returned directly to the pump suction. •Suitable for medium pressure system in marine application.

Closed Loop System

Centralized Hydraulic Power System

Hydraulic Systems

Centralized Hydraulic Power System • Centralized hydraulic are common in large tanker -> safety limitation limit electrical and steam installation • Deficiency lie on system cleanliness and venting work as well as compatibility of function • Accessibility for flushing and • Avoidance of pockets and voids that will tend to collect foreign material .

Design consideration - Hydraulic •

Possible arrangement of centralized hydraulic systems: 2. Bower anchor windlass and forward mooring equipment on one system 3. Cargo, topping , vang wing and hatch cover on one system. 4. All hull material except , the steering gear on the same system In 1 and 2 the pumping units will be located closed to the driven equipments where as in 3 the main will be log and the pump will be located in the engine room. .

Design consideration - Hydraulic • The steering gear is left out in 3 because of small fraction of power need and the it availability in case of defective hydraulic hydraulic line • Environmental consideration – most hull material are located where they cannot be heated. • Fluid tank heating

Design consideration - Hydraulic • Corrosion resistance piping + Hull thickness allowance for corrosion • Gauge snubber -> avoid pulsating pressure • Sump capacity- 110percent of the oil volume • Strainer • Filter fluid cleanliness indicator

Design requirement -Mechanical Equipment subject to use under seaway • Pitch of 10 deg (bow up or bow down) • Permanent trim of 5 deg by bow or stern • A roll of 30 deg (each side) • Permanent list of 15 deg (either side) -> probability of one event at a time -> driving and driven equipment on same bedplate- otherwise deck deflection allowance should be assigned.

Design requirement -Mechanical Bearing that will be subject to high impact like the wild cat of winch -> good grade bronze • Interior should be sand blasted, cleaned and gasket maintenance access is should be provided. • No compromise should be made on strength. No compromise from strength, calculation adjustment is allow to compensate from intermittent

Design requirement -Mechanical • Reduction gear should be totally enclosed and provided with oil bath lubrication, with means for filling, draining, and measuring the lubricant level in accordance with standards. • At design stage, thus allowance can be seized on advantage derived from intermittent usage. Wear load factor that can be assigned is shown below. • Load capability should be given careful analysis

Design requirement –Electrical • Equipments: Drip roof or watertight protection (+ automatic drainage fitting) Ventilated Bearing –> lubricated and sealed Sound brake -> 200% of normal operating load Hand release mechanic to handle emergency situation. Limit switch should rugged master switch could be sprig loaded for voluntary release Overvoltage and under voltage Provision of heater DC over AC -> system response

Anti friction should be at location subject to wear, positive alignment , minimum lost motion ie, motor bearing steering gear control assembly, worm wheel shaft, mooring tension sensing assembly. piping -flexibility require for hydraulic system/ air trapping avoidance ->watertight on deck motor and deep proof under the deck motor ->Motors- sleeve and antifriction types