DIP Leakage Test - Pressure Increasing
DIP Leakage Test - Pressure Increasing
(OP)
I am currently witnessing a leakage test on an 8" DIP. The test requires the contractor to maintain a constant pressure in the line (by adding more water if leakage occurs), and then to measure the total volume of water added over the course of the test.
The first go-a-round, over the course of 4 hours, the pressure in the pipeline increased from 150 PSI to 200 PSI. I pointed out that the pipe was not buried and that the temperature increase was most likely causing the pressure increase. The contractor buried part of the line (but not the entire line, as they have work that requires portions of this trench to remain open) and began the test again today. Less than an hour in, the pressure is still rising (although not as dramatically as before). Without making the contractor fill in the entire trench, is there a way to perform this test properly?
The first go-a-round, over the course of 4 hours, the pressure in the pipeline increased from 150 PSI to 200 PSI. I pointed out that the pipe was not buried and that the temperature increase was most likely causing the pressure increase. The contractor buried part of the line (but not the entire line, as they have work that requires portions of this trench to remain open) and began the test again today. Less than an hour in, the pressure is still rising (although not as dramatically as before). Without making the contractor fill in the entire trench, is there a way to perform this test properly?





RE: DIP Leakage Test - Pressure Increasing
You probably have air in the pipes. Have the pipe flushed adequately prior to the test.
RE: DIP Leakage Test - Pressure Increasing
About only other thing I can think of (and this would admittedly/probably be a very rare case) is if by any chance your happen to be testing against a test boundary consisting of a closed valve with higher pressure on the "other" side, and you have a leak bleeding by that side onto your new test section!
[All that being said, I wouldn't be surprised if you have a good line with still increasing pressure after 4 hours!]
RE: DIP Leakage Test - Pressure Increasing
RE: DIP Leakage Test - Pressure Increasing
One would suspect that a slug of water pushed down the pipe to get that kind of pressure drop. I don't think it was the sun.