absorbers/dampers

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Sat 20 Aug 2005 15:19
absorbers/dampers - dannydamanny
Hi

I have a 95 nissan 100NX and while looking for a nail in my tyre i noticed the rear suspension could probably do with replacing.
i showed 2 people, 1 said 1 need new shocks, 1 said dampers.

are these the same thing or 2 seperate parts?

Thanks
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Sat 20 Aug 2005 16:40
absorbers/dampers - Cyd
'Dampers' is the proper physics term. Otherwise known as shock absorbers or shochers or shocks.

If this is the first time the car has required dampers you should really replace all four at the same time. Two new at one end with two worn at the other will result in the car being unstable under load or tricky situations and may lengthen your braking distance considerably in the event of an emergency stop. Tyres can only grip the road to their maximum capability if they are held down effectively - dampers contribute enourmously to this process by damping the high frequency, low amplitude oscillations of the unsprung mass system.
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Sat 20 Aug 2005 18:59
absorbers/dampers - trymybest
Not meaning to be pedantic but the term shock absorber applies to the spring.You have only to follow a vehicle with faulty dampers to se the effect they have.
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Sat 20 Aug 2005 19:05
absorbers/dampers - SjB {P}
'Dampers' is the proper physics term.


Indeed.

The springs are shock absorbers as they absorb the shock of driving over an irregularity in the road surface, whereas the dampers (an oil or gas filled tube, usually) stop the spring and assembly attached to it oscillating as it otherwise would.

For some reason that I know not though, all around me seem to call springs "springs" (fine) but dampers "shock absorbers" (not fine!)

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Sat 20 Aug 2005 19:34
absorbers/dampers - none
Prior to the 60's they always used to be called dampers. When the MOT was introduced, the authorities decided to call them shock absorbers, and this has become the everyday term for dampers.
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Mon 22 Aug 2005 13:51
absorbers/dampers - Old Banger
Prior to the 60's they always used to be called dampers.
When the MOT was introduced, the authorities decided to call them
shock absorbers, and this has become the everyday term for dampers.



The term "shock absorber" should refer to the combination of both spring and damper. Individually, they're not much use!
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Mon 22 Aug 2005 22:22
absorbers/dampers - none
Old Banger,
I suppose that the road spring takes the initial shock, and then the damper absorbs the energy within the stressed road spring.
Maybe they should be called ' shock dampers'. That would suit everyone. !
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Mon 22 Aug 2005 22:38
absorbers/dampers - Number_Cruncher


I suppose that the road spring takes the initial shock, and then the damper absorbs the energy within the stressed road spring.



Quite a good way of putting it I think.

In terms of energy, the spring can temporarily store an excess of energy, while the damper can convert energy to heat, and therefore remove it from the dynamic system.

Another way to seperate the behaviour of spring and damper is to say that a spring produces force which depends only on position. A damper produces force which depends only on the velocity with which it is being opened or closed.

To complicate matters a little, there is usually more rebound damping than bump damping.

The term shock absorber is, despite being all too common, technically illiterate.

Number_Cruncher

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Tue 23 Aug 2005 01:18
absorbers/dampers - Aprilia
When I was a lad (1960's) we generally called them dampers. I think the term 'shock absorber' came in from the USA.
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