Pressure testing of floating ball valve, client side
Thread Content
Pressure testing of the floating ball valve: passed the inspection by the client’s factory； Before installation, a pressure test was conducted on-site; what is the reason for the leakage at the valve seat?
There were omissions in the factory inspections; not every item was checked, or the inspections were not thorough enough.
The 300LB floating ball passed the factory pressure test – why did it fail the customer’s pressure test?
The sealing ring is damaged; pressing the ball several times scratches the sealing ring, thus damaging it. This indicates that the internal design of the valve is unreasonable – perhaps it can be pressed successfully once, but not a second time. Additionally, the material of the sealing ring is of poor quality and does not meet the standards. At the factory, only a simple air-seal pressure test was carried out, but when testing at the client’s site, proper standard tests were conducted, including tests to determine strength and water pressure, with acceptance based on standard procedures. The high pressure damages the internal sealing elements and valve seats.
These reasons are impossible: 1. Sealing component manufacturers are suppliers that have withstood long-term testing, and such new products do not have problems with performance as poor as that of junk； 2. It is a legitimate valve manufacturing enterprise, not a home-based workshop: 1) Valves are tested strictly in accordance with standards before leaving the factory, 2) Pressure gauges are calibrated, 3) The testing requirements are higher than the standard ones.
I’ve encountered similar problems before; it was an 8\" 150LB floating ball valve. It worked fine during pressure testing in the factory, but 2 months later, after being shipped overseas to the customer, 80% of the valves started leaking. The valves passed all pressure test requirements in the factory, yet they were leaking heavily once they arrived at the customer’s location. Upon disassembly and analysis, it was found that the material of the valve seat seal had undergone cold flow deformation. The customer replaced all the valves with new seals, and eventually the leaks were stopped. The main reasons for leakage in ball valve seats are improper selection of materials for the seat and damage to the sealing elements.
Apart from what was mentioned on the 6th floor, are there any issues caused by transportation?
If it was working properly before installation, then if there is a leak when it’s installed on the pipe, it’s likely that it wasn’t installed properly, or the pipe wasn’t fitted carefully, resulting in a side leak
That makes sense; perhaps the customer chose the wrong material.