ASTM A 335 - Can we go with UT instead of Hydrotest

Hi All,
I would like to know can we go for UT instead for Hydro test ?
If yes then is there any thickness constraint ?
Pl mentioned the code reference....

Regards
HNJ

Hello All,

I am waiting for your reply...

Please reply , or whatever it is please put the openion..
Please reply

Regards
HNJ

UT testing is a "spot test" to determine the wall thickness at that point ONLY. My experience, this is done randomly down a pipeline or vessel to do a field check as to the condition of existing piping/equipment. I've never heard of it being used to verify the strength or continuity of a welded joint. However I do know that they can use X-ray testing to check welded joints, this is normally done on the "golden weld" (last weld where you are tying in a new system to an existing system ...the one you can't hydro-test). BUT I do see this type of testing being done more & more on whole systems; this is becoming a common occurrence in my area. Hydro-testing is cheaper, but with the X-ray testing is available (...and readily done in the field). Good Luck!

If the line class calls for 100% RT then it is OK. This happens with some pipe specs where all welds are to be X rayed. You had better check with your materials engineer if it isn't shown in the Pipe Spec or Line List.

Thanks a lot for reply.
But this question arises when i saw ASME SEC-II PART A SA335 Section 11. Please Refer

Just to make sure everybody is on the same page here …


UT testing is “Ultrasonic Testing” …it uses high frequency sound energy to conduct examinations, determines measurements (thickness), and provides instantaneous results.

RT testing is “Radiographic Testing” (X-ray testing) …radiation is used to examine welds by passing radiation through the weld to film in a holder on the opposite side for a determined amount of time. This produces a picture of the weld and any faults (if present).

…FYI