Suspension spheres. How do they work?

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ktaylor21662
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Suspension spheres. How do they work?

Post by ktaylor21662 »

I've never fully understood how the spheres operate. Mine need replacing; that is obvious to me. But could someone discribe their operation to me. It will give me a better understanding of the ride problem I have. Kevin.
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Post by jeremy »

Have a look at this link - it should tell you all you need to know about Citroens - including the hydraulics.
http://citroen2.triger.com.pl/kc/pdf/citguide.pdf
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Post by JohnT »

In simple terms there is a bag of fluid which is under pressure from the weight of the system and the stress put upon it. Within this sphere there is a pocket of gas which can be compressed or deflate against this pressure, so there is flexibility which is what the system is about..... the forces of pressure and that of resistance, working together. Clear as mud eh?
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Post by JohnT »

If you want a better understanding of the system and you have time have a look at this well informed website,
www.tramontana.co.hu./citroen/ It is very good.
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Post by Peter.N. »

I will do my best. The metal 'sphere' contains a diaphragm behind which is nitrogen gas or air would do as well. When the hydraulic pressure starts to rise, fluid enters through the orifice that you can see when the sphere is removed, and pushes on the diaphragm compressing the gas behind it, as the pressure increases it moves the diaphragm back until the pressure is equal in front and behind. As the suspension moves up it pushes more fluid into the sphere and compresses the gas which act like a spring, pushing fluid back into the suspension strut as the suspension falls. It in effect works like blowing up a balloon. When the car is at rest with the engine running the pressure is equal in the sphere and the strut, as soon as you start to move the movement of the suspension is effectivly passed on to the sphere.
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Post by Peter.N. »

All these other replys came in while I was typing this! Well done lads.
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Post by citronut »

quarter inch thick nylon blader not diaphragm pumped up to aprox 700 psi with nitrogen,some people say the sphere is the spring and the ram is the damper others say its the other way around regards malcolm
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Post by JohnT »

Isn't this what it is all about? Great post Peter.N.
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Post by Peter.N. »

Thank you! I stand corrected
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Post by Chrispy »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by citronut</i>

quarter inch thick nylon blader not diaphragm pumped up to aprox 700 psi with nitrogen,some people say the sphere is the spring and the ram is the damper others say its the other way around regards malcolm
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
I think the sphere kind of acts as both doesn't it? The air in the sphere itself acts as the spring (boucing up and down) and the valve baffle in the sphere's opening acts as the damper, effectivly slowing the movement of LHM to restrict the bounce. All the ram does is to transfer the movement of the wheel/ hub assembly up to the sphere. It contains nothing bouncy inside like a spring and no damping of it's own as the sphere's baffle does that.
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Post by rbruce1314 »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Chrispy</i>
and the valve baffle in the sphere's opening acts as the damper, effectivly slowing the movement of LHM to restrict the bounce.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Which is why accumulator spheres are different because they have no baffle/restrictor so no damping effect.
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Post by Chrispy »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by rbruce1314</i>

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Chrispy</i>
and the valve baffle in the sphere's opening acts as the damper, effectivly slowing the movement of LHM to restrict the bounce.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Which is why accumulator spheres are different because they have no baffle/restrictor so no damping effect.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Precisely. [:D]
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Post by ktaylor21662 »

Many thanks. It is much clearer now. Kevin.
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