Penstock Hydrostatic Test
Penstock Hydrostatic Test
(OP)
For Penstocks: Can the hydrostatic test be susbstituted by 100% UT inspection on all welded joints?
Or the hydrostatic pressure test is mandatory?
thanks
Or the hydrostatic pressure test is mandatory?
thanks





RE: Penstock Hydrostatic Test
sgarro, as a manner of general information for you, read these threads: thread404-277324: Time duration for a pressure test
thread378-269828: TIME OF DURATION OF HYDROSTATICS TEST PRESSURE
RE: Penstock Hydrostatic Test
RE: Penstock Hydrostatic Test
Actually I´ve looking for that document and I cannot find it anywhere, do you know where can I get it?
Thanks
RE: Penstock Hydrostatic Test
RE: Penstock Hydrostatic Test
RE: Penstock Hydrostatic Test
The purpose of the hydrostatic field test is primarily to determine if the field joints are watertight. So the question is then: Can being watertight be checked by the UT?
In doing hyd. test, the test pressure should be maintained for at least 2 hours and there are permissible values for leakages. This makes me suspect that UT can be interpreted as a sign for being watertight.
Engineering monograph No.3, Weld Steel Penstocks by US department of the interior bureau of reclamation, states: "A proof hydrostatic test on the penstock after installation if most desirable. If the entire penstock cannot be tested hydrostically, individual sections may be tested in the shop after they have been radiographed. Hydrostatic tests should be performed .... to prove adequacy of all plates and welds with the required margin of safety."
I would say that a UT cannot assure the intentions of a hydrostatic test.
RE: Penstock Hydrostatic Test