Why hydrotest

Once the test procedure is approved, the test arrangement is set up. This includes test equipment like manifolds, gauges, chart recorders and temperature recorders, as well as temporary vent valves etc as needed.

A typical test set up and manifold arrangement is shown below:. Systems to be hydrostatically tested are filled gradually from a water source or tanker ensuring the fill rate is according to test procedure.

System is also vented during filling to ensure elimination of air pockets. Pressurisation starts after the entire system has been filled and isolated. This is also the time when we inspect for any leaks of buckling. Some tests allow pressure to be topped up during test with make-up water. During draining vent valves are usually kept open at the highest point of the system to prevent vacuum. If a piping system is to be dried by blowing, drains or vents are opened in order to avoid pressuring the system.

Piping that is hydrostatically tested, is dried by either hot air blowing, or with nitrogen. Hydro test records and test reports are then generated and signed off signalling the successful conclusion of the test and system proceeds to the next stage of completion.

Jump to content. Low Flow in Pipes - posted in Ankur's blog. Posted 05 October - AM. Why not other fractions i. Is there any reason for specifing 1. Thanks and Regards, Chandru. Posted 06 October - PM. Posted 07 October - AM. Posted 08 October - AM. Chandru, Due to the hazard of released energy stored in compressed gas , i think ASME piping codes e. Hope, you would be satisfied by this explanation. Posted 10 October - AM. Posted 20 February - PM. So obiously the Allowable material Stress value is high at R.

T rather than design temp.? So what is the use of doing hydrotest at room temp? About your second question you should be informed in all cases hydro test pressure would be calculated along with the correction due to allowable stress difference in room temperature and design temperature As falllah explains, for e.

A creep test is a pressure test variation used to locate component leaks. Creep, a. A creep test is one of the final steps of quality control in the welding process before the product arrives to the customer. A creep test entails the blocking and sealing of tubing. Next, the technician pumps nitrogen into the tube. Nitrogen prevents moisture forming during the test, keeping metal from oxidizing.

A plastics creep test occurs at least 12 hours after welding, giving the weld 12 to 16 hours to cure. Then, a creep test for leaks takes place using the same method as metal creep testing.

On the flip side from pressure testing, is vacuum testing where the product is tested from the outside-in. First, the product is evacuated, and then helium is lightly sprayed onto a potential leak area.

Helium that can be detected on the inside of the device, after the test is administered, confirms there is a leak. The product will need to be repaired or even discarded, depending on the intensity of the leak. The test involves creating a vacuum, as opposed to applying pressure.

Then, the product is tested for leaks.