Design with 1% of yield strenght

[raulcc]

thread794-467405

Good morning Eng Comunity.

I would like to know in which case is possible to use 1,0 % proof strength in the design thinkness of a tank.

Kind regards,

 

[LittleInch]

Your title seems to be misleading.

I think what you mean is design using a yield stress based on 1% strain?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[raulcc]

Yes, you can also view it in that way.

1% offset yield strength is obtained by moving in the strain (x) 1% and draw a parallel line from the elastic range.

Normally is used 0.2%

My question is, what is the criteria to use 1% offset yield strength? (more that the ovious higher yield value)

 

[MJCronin]

Wild, kinda off the wall question here ..... WHAT IS YOUR CODE OF RECORD FOR THE DESIGN THIS TANK ?

... or are you just kinda messin around in the back yard with some scrap sheet metal seein what you can build.

You are not doing this for a client or anything like that ?.... Right ??

MJCronin
Sr. Process Engineer

 

[LittleInch]

Why bother?

I can't see the difference between 0.2% and 1% strain being significant enough to make any difference??

Strain based design is used where you get rare but very high loads. The issue is that once strained it doesn't go back so then what do you do? Scrap the vessel?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[DriveMeNuts]

An obvious answer is, if the code says you can.

 

[EdStainless]

Considering that virtually none of the alloys that we use actually have a linear section to the tensile curve, and that yield strength is an engineering construct and not a material property this is a minor issue.
Read the rules (Code).

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