Why Are Torsion Bars Handed?

[309PUG 2 1 Cars]

Yes, there is a difference in the bars. Im pretty sure the torsional strength and spring rate in them only works twisting one direction. What you have to bear in mind is the splines are pitched differently at either end, so a right hand side bar wont fit a left, are you with me???? (Thats the way I understand it anyway)

 

Maxi

 

 

Sorry to piss on your bonfire but that is way off the mark. It is impossible to manufacture a torsion bar so it will only work twisting one way. Are you mad ?????

 

New TB's are are identicle in every way, absoulety no idea why Peugeot would gave diff part numbers, probably to confuse us all, it appears to be working.

 

Chris

Edited September 5, 2008 by 309PUG

[allanallen 528 2 Cars]

it appears to be working.

 

what, who, where am i

[gazzamec 0]

torsion bars are made by twisting bars of steel in one direction and passing them through heat cycles to give the "bar" spring characteristics, it is designed to only twist one way,

just like a spring, there are 2 types, compression and extension each is made differently,the TBs look like a solid bar but it isnt, a L/H TB will be made by twisting the "bar" anti-clockwise and the R/H one will be twisted clockwise.

 

however i fail to understand how the antiroll bar works properly as that is also of a spring design and is twisted in only one direction, this would in theory give one way a different rate of compensation against roll than the other.

 

good topic BTW

[jackherer 543]

absoulety no idea why Peugeot would gave diff part numbers

 

The different number of painted stripes is enough to justify different part numbers, even if the bars are otherwise identical.

[allanallen 528 2 Cars]

torsion bars are made by twisting bars of steel in one direction and passing them through heat cycles to give the "bar" spring characteristics, it is designed to only twist one way,

just like a spring, there are 2 types, compression and extension each is made differently,the TBs look like a solid bar but it isnt, a L/H TB will be made by twisting the "bar" anti-clockwise and the R/H one will be twisted clockwise.

 

however i fail to understand how the antiroll bar works properly as that is also of a spring design and is twisted in only one direction, this would in theory give one way a different rate of compensation against roll than the other.

 

good topic BTW

 

so if i buy bars off 205parts,xsport,shenpar etc will they have been heat treated in this manor?

[Pugnut 9 1 Cars]

i was wondering if its anything to do with where the bars sit on the swing arm . I cant fathom it out in my own little head , but you know how one bar is fwd and one aft of the pivot point , well is there different leverage on both of these due to their distance from the wheel , or is that nonsense due to the fact that they are both equal distances from the pivot point? it would explain different bars , different spring rates??

 

just a thought and probably bollocks!

 

Al

[allanallen 528 2 Cars]

i was wondering if its anything to do with where the bars sit on the swing arm . I cant fathom it out in my own little head , but you know how one bar is fwd and one aft of the pivot point , well is there different leverage on both of these due to their distance from the wheel , or is that nonsense due to the fact that they are both equal distances from the pivot point? it would explain different bars , different spring rates??

 

just a thought and probably bollocks!

 

Al

 

as you say, i dont think it would make a difference as they are the same distance from the pivot

[base-1 17]

torsion bars are made by twisting bars of steel in one direction and passing them through heat cycles to give the "bar" spring characteristics, it is designed to only twist one way,

just like a spring, there are 2 types, compression and extension each is made differently,the TBs look like a solid bar but it isnt, a L/H TB will be made by twisting the "bar" anti-clockwise and the R/H one will be twisted clockwise.

 

however i fail to understand how the antiroll bar works properly as that is also of a spring design and is twisted in only one direction, this would in theory give one way a different rate of compensation against roll than the other.

 

good topic BTW

 

Is the first part of your statement definite, absolute, 100% fact that you are experienced with? The bars are heat treated under torsional load? I'm not questioning your accuracy, just I don't know (and obviously nobody else who has posted so far does for certain!) so want to check.

 

Assuming it is true, that would explain any potential difference between left + right bars. My assumption for the Anti Roll bar would be that there is no load placed during heat treatment, so spring rate is the same in either direction.

[allanallen 528 2 Cars]

The bars are heat treated under torsional load

 

i'm not convinced

[gazzamec 0]

Is the first part of your statement definite, absolute, 100% fact that you are experienced with? The bars are heat treated under torsional load? I'm not questioning your accuracy, just I don't know (and obviously nobody else who has posted so far does for certain!) so want to check.

 

Assuming it is true, that would explain any potential difference between left + right bars. My assumption for the Anti Roll bar would be that there is no load placed during heat treatment, so spring rate is the same in either direction.

 

not under torsional load no, they are made from the raw "bar" the material they are made from, they are twisted to change the structure of the metal then heat treated to give them the strength needed.

 

different applications use slightly differring process.

 

to draw comparison think of it like a composite pole, if the fibres of the composite are all in line length ways the strength is very low, however wrap the fibre round the pole and its strength is vastly increased giving a much higher torsional strength also.

[309PUG 2 1 Cars]

not under torsional load no, they are made from the raw "bar" the material they are made from, they are twisted to change the structure of the metal then heat treated to give them the strength needed.

 

different applications use slightly differring process.

 

to draw comparison think of it like a composite pole, if the fibres of the composite are all in line length ways the strength is very low, however wrap the fibre round the pole and its strength is vastly increased giving a much higher torsional strength also.

 

I find it very hard to believe what you are saying, I thought that the main reasons for spring steel to have it's fundamental properties is down to the addatives mainly silicon, and the heat treatment processes it goes through. I don't believe they twist the bar to generate the 'torsion' / spring effect while being heat treated.

 

Chris

[Tom Fenton 1,525]

No permanent structural change occurs by simply applying torsion to the bar. Heat treating the bar will change the grain structure within it, which will in turn along with the alloys in the steel give it the properties required.

If you were to heat treat a twisted bar all that would happen is the grains would rearrange themselves in uniform fashion, giving absolutely no different end result.

All this talk of heat treating a twisted bar is poppycock.

 

Tom

Works in a steelworks.

[AdamP 0]

Tom = correct. The heat treatment would cancel out any effects of the twisting!

[gazzamec 0]

No permanent structural change occurs by simply applying torsion to the bar. Heat treating the bar will change the grain structure within it, which will in turn along with the alloys in the steel give it the properties required.

If you were to heat treat a twisted bar all that would happen is the grains would rearrange themselves in uniform fashion, giving absolutely no different end result.

All this talk of heat treating a twisted bar is poppycock.

 

Tom

Works in a steelworks.

 

good man for the gen, i was always taught that spring steel and torsion bars alike were in fact twisted before being heat treated to add the additional strength and characteristics.

 

i stand corrected