SpudFiles

Just wondering how others figure out the bursting pressure of different size steel vessels from given yield and tensile strengths.

http://www.engineersedge.com/pipe_bust_calc.htm

Remember to include a safety factor, also taking into account any threads, holes, seams, deformations, finishes (eg. annealed, hot roll etc) and only use it as a rough ballpark figure.

inonickname wrote:http://www.engineersedge.com/pipe_bust_calc.htm

Remember to include a safety factor, also taking into account any threads, holes, seams, deformations, finishes (eg. annealed, hot roll etc) and only use it as a rough ballpark figure.

Cheers.

It seems to say my cylinder has a bursting pressure of 94,300psi which seems about right I hope.

Do you know of any way to calculate the thread specifics by any chance? (thread diameters and pitch) ie. Best suited for certain tasks?

Jolly Roger, if it says the bursting pressure is 94300psi, you've got a thick-walled vessel, which that calculator is not suited to. Also, a more useful figure to you is yielding pressure, not burst pressure. You can use btrettel's results from this thread to find the yield pressure of the vessel you're building to a very good approximation. Actual rupture of the vessel is a more complicated problem, but btrettel may be able to help you with it. As D_Hall comments in the thread I linked you to though, a bent part is often just about as useful as a broken part - you may want to simply design around preventing plastic deformation (with typical pressure vessel materials like softer steels there's a very large gap between permanent deformation and actual rupture).

Jolly Roger wrote:Just wondering how others figure out the bursting pressure of different size steel vessels from given yield and tensile strengths.

SoildWorks / Cosmos

I converted the formula from DYI's thread into a spreadsheet for my own convenience. It is attached to this message.

Cheers guys, I'll give that a go.

Also Velocity, I was just about to ask whether solid works can calculate such things. Didn't even have to ask

Any luck on the threads?

Jolly Roger wrote:Cheers guys, I'll give that a go.

Also Velocity, I was just about to ask whether solid works can calculate such things. Didn't even have to ask

Any luck on the threads?

Well, it depends. Tapered pipe threads seal easily, and are compatible with pre existing parts. Straight threads have less compatibility, and will require additional sealants like o rings, washers and adhesives. Coarser threads will give you more thread contact, but will cut deeper into your parts, and are more aggressive, opening up windows for damage. The size of the threads will come naturally with the part.

You should be able to calculate forces and stresses on threaded connections pretty easily, which will help you out in deciding thread type, size and length.