Use of Non-Standard Blind for Hydrotest
Use of Non-Standard Blind for Hydrotest
(OP)
Hi,
Contractor proposed to use non-standard blind in lieu of standard blind for hydotest? They claimed that the thickness calculation is still follwoing ASME B31.3.
Is it common to use non-standard blind for the hydrotest?
ppm
Contractor proposed to use non-standard blind in lieu of standard blind for hydotest? They claimed that the thickness calculation is still follwoing ASME B31.3.
Is it common to use non-standard blind for the hydrotest?
ppm





RE: Use of Non-Standard Blind for Hydrotest
I would not let this become the normal operating procedure.
If there is any question check around and see if someone rents the blinds especially the larger diameter and higher Class flanges.
RE: Use of Non-Standard Blind for Hydrotest
In my experience, it is quite normal to fabricate a non-standard blind on site for a test.
David
RE: Use of Non-Standard Blind for Hydrotest
http://
This topic has been discussed repeatedly in these fora..
-MJC
RE: Use of Non-Standard Blind for Hydrotest
http://www.usaindustries.com/PIPING-PRODUCTS.pdf
Banu, in what area of the world is your facility ?
RE: Use of Non-Standard Blind for Hydrotest
If this is true I would require that they send a copy of their calculations of the blind adequacy for approval.
If they pass the requirements of B31.3 for blinds (appropriate use of materials, stresses correct for rated temp, ect), I would approve their use and be done with the matter.
Under no circumstances would I take their word that their NS flange "will be OK " without seeing calculated proof that I could verify. If you don't have access to the code, get a copy.
Just my two cents worth.
Always remember, free advice is worth exactly what you pay for it!
RE: Use of Non-Standard Blind for Hydrotest
My caution is that it is quite common for people to also fabricate non pressure rated "vapor barriers" which can easily be confused with fabricated pressure rated blinds. Consequently, I much prefer purchased, stamped and marked blinds. I would request proof and confirmation of blind adequacy prior to accepting field fabricated blinds.
RE: Use of Non-Standard Blind for Hydrotest
jt
RE: Use of Non-Standard Blind for Hydrotest
It has already been discussed.
thread378-215611: Hydrotest Failure & Fatality