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VISVESVARAYA TECHNOLOGICAL UNIVERSITY BELGAUM-590018

A Seminar Report on "GAS SHOCK ABSORBER"

Submitted in the partial fulfilment of requirement for the award of

BACHELOR OF ENGINEERING IN

MECHANICAL ENGINEERING

Submitted by SHASHIKUMAR REDDY M R (1BY12ME409)

For the academic year (2014-15)

Under the Guidance of Dr K.M. SATHISH KUMAR

Associate professor,

Department of Mechanical Engineering BMS INSTITUTE OF TECHNOLOGY& MANAGEMENT

(Affiliated to Visvesvaraya Technological University) Doddaballapura Main road,

Avalahalli, Yelahanka, Bangalore-560064

The shock absorber is an integral part of the car's safety, and having shock absorbers in good condition is just as important as having good brakes, tyres and active safety systems.

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Gas shock absorbers represent an advance over traditional shock absorbers. At high speeds, the flow of oil in the cylinder can cause foam of oil and air to form. This limits the optimum through put of the flow in the valves. The addition of nitrogen gas under pressure into shock absorbers , this results increases efficiency.

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Single tube with high pressure Twin-tube with low pressure

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Gas shock absorbers operate on the same basic principle of movement of the piston in an oil filled tube but they contain, at one end, a small quantity of nitrogen under high pressure (25 bars).

The floating piston is prevented from mixing of the oil with the gas .

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Due to the constant pressure in the single tube gas shock absorber , this constant pressure eliminates cavitation and foaming which could degrade the effectiveness of the shock absorber.

In the twin- tube shock absorber, at top of the reserve tube, nitrogen under relatively low-pressure. This low pressure is to improve the efficiency of the shock absorber.

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Some basic principles need to be respectedwhen installing shock absorber: Consult the main catalogue. Air wrenches Tools Cartridge replacement Tighten the mounting Torque wrenches Check and adjust

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DESIGN

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Incorrect spring action may produce a fork angle that is too steep or too flat. This in turn will give a tendency for over steering or under steering, which could seriously affect the handling characteristics of the motorcycle.

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1. MEASURING

 

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Instantaneous response

Better fade resistance

Better durability

No need for re-adjustment

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At high speed, when shock occurs there will be mixing of fluid and air and also continuous use of the fluid increases the temperature will reduces damping effect. Hence by using gas shock absorber we can overcome from these problems and increases efficiency.

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THANK YOU

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