hollow LHS axle

[rickp78]

hey guys just wondering if anyone knows why Nissan use a hollow axle on the LHS front?? I snapped it a few weeks back and have since found out after my mechanic made several calls no body has ever heard of a hollow axle. Just wondering if there is a swap for it or what can be done to make it stronger.thanx

 

[Chubby]

hollow LHS front axle

I broke mine on the weekend after fitting a front diff locker. Went out for a 4wd after fitting and snapped on first test but pushed it hard. Now i know it is a weak spot i will be a bit easier on it from now.

 

[shan_b]

Just food for thought,
From an engineering aspect, you would be surprised how strong a hollow tube is compared to a solid.
Without going to extremes, weight saving Vs strength, hollow tubes perform extremely well in pretty much all loading conditions

 

[fourocker]

Agreed, hollow tubes are more resistant to torsional stress and lateral bending, it's not necessarily a weakness, drive shafts are that way now and have been for ages, it requires better engineering practice but saves on raw material weight. It's common practice in industry these days I'm finding.

 

[bjsnavara]

got two

got two in my yard im in shepp also two used cv woulld make good spares

 

[Dave]

Any pics ?

 

[bjsnavara]

farrrk

i will send you phone number in private messages and i can text you a photo

 

[180degrees]

Just food for thought,
From an engineering aspect, you would be surprised how strong a hollow tube is compared to a solid.
Without going to extremes, weight saving Vs strength, hollow tubes perform extremely well in pretty much all loading conditions

Agreed, hollow tubes are more resistant to torsional stress and lateral bending, it's not necessarily a weakness, drive shafts are that way now and have been for ages, it requires better engineering practice but saves on raw material weight. It's common practice in industry these days I'm finding.

You guys talking strength to weight ratio right? cause 2 bars of the same diameter 1 hollow and 1 solid the solid is always going to be stronger, you can prove it mathematically.

Not disputing the usefulness of a hollow tube though.

 

[Old.Tony]

You guys talking strength to weight ratio right? cause 2 bars of the same diameter 1 hollow and 1 solid the solid is always going to be stronger, you can prove it mathematically.

Not disputing the usefulness of a hollow tube though.

There are differences between solid and hollow.

A solid pipe will take more weight along the length of the pipe (that means suspending the weight from the pipe which is held vertically -> || <- like that. A hollow pipe doesn't have as much material to spread that sort of load over thus will fail to hold as much strain when used like that.

If you use the pipes horizontally like this -> = <- and suspend a weight from the middle, a solid pipe will bend much easier. The reason is that the solid pipe has something to bend on - itself. The hollow pipe will fracture after you've exceeded the tension limit of one side of the pipe (the outer radius of the bending moment) - the inner will compress.

Solid pipes perform slightly worse than hollow for similar reasons to the bend - there's something that the pipe can twist around centrally where a large amount of force acts on a small cross-section (the centre). In the hollow pipe, there is no small cross-section for the force to act on, so if the pipe is manufactured well, it will withstand considerable torsional stress.

Our axles are never subjected to the bending actions unless you land really badly on an unfortunately-shaped hard obstacle. They are subjected to twisting actions which hollow pipes perform better at.

 

[fourocker]

Generally yes, perfect example, just imagine the tow bar assembly on the nav if it was made from completely solid steel, just not practical or necessary.

 

[180degrees]

There are differences between solid and hollow.

A solid pipe will take more weight along the length of the pipe (that means suspending the weight from the pipe which is held vertically -> || <- like that. A hollow pipe doesn't have as much material to spread that sort of load over thus will fail to hold as much strain when used like that.

Of course stress = force/area

If you use the pipes horizontally like this -> = <- and suspend a weight from the middle, a solid pipe will bend much easier. The reason is that the solid pipe has something to bend on - itself. The hollow pipe will fracture after you've exceeded the tension limit of one side of the pipe (the outer radius of the bending moment) - the inner will compress.

Being soild or hollow has little to do with that, the hollow pipe has a low moment of inertia, its why I beams can carry huge loads, they have very high moments of inertia.

Solid pipes perform slightly worse than hollow for similar reasons to the bend - there's something that the pipe can twist around centrally where a large amount of force acts on a small cross-section (the centre). In the hollow pipe, there is no small cross-section for the force to act on, so if the pipe is manufactured well, it will withstand considerable torsional stress.


Our axles are never subjected to the bending actions unless you land really badly on an unfortunately-shaped hard obstacle. They are subjected to twisting actions which hollow pipes perform better at.

No they don't, two pipes of the same size one solid one hollow, the soild pipe has a much higher polar moment of inertia and is therefore able to resist twisting more effectively (looking normal to a vertical cut through the bar)

its just the stress varies linearly from the center (0%) to the extreme fibers (100%) so you can actually cut out a large portion of the solid pipe as it doesn't really do that much. what you and everyone else are talking about is strength to weight ratio im pretty sure.

 

[shan_b]

Didn't mean to start a mechanics discussion.

my bad

 

[180degrees]

lol yea sorry I came across as a bit of a dick, just wanted to clarify (from what I have read in text books anyway) the properties of two bars the same size but hollow/solid.