Maximum stress during Hydro-test 1

[sagar251183]

Friends
What are the parameters to decide the permitted percentage of maximum stress during Hydrotest?
Mostly 90% of yield is maximum stress during test but sometimes 76% or less used.
Please reply if u know the answer.

 

[XL83NL]

Depends on your design Code. B31.3 345.4.2 (c) states;

if the test pressure as defined above would produce
a nominal pressure stress or longitudinal stress in
excess of the yield strength at test temperature or a
pressure more than 1.5 times the component rating at
test temperature, the test pressure may be reduced to
the maximum pressure that will not exceed the lesser
of the yield strength or 1.5 times the component ratings
at test temperature.

 

[stanweld]

Hydrostatic testing of cross country pipelines is often done at pressures along the line due to elevation differences at 105% of SMYS and greater.

 

[SnTMan]

Permanent deformation is to be avoided.

Regards,

Mike

 

[btrueblood]

We often test our castings to burst...

 

[zdas04]

I'm not buying tested castings from you.

David Simpson, PE
MuleShoe Engineering

"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
The plural of anecdote is not "data"

 

[handleman]

So... If you test to burst, you are looking for the test to fail, right? As in you couldn't burst it?

-handleman, CSWP (The new, easy test)