Help for leakage of liquid alkali pipeline valves and flanges
Thread Content
The valves and flanges of the 32% liquid alkali pipeline are leaking as shown in the picture. Can you please tell me what kind of sealing ring should be used in the flange and whether the ball valve is suitable for the liquid alkali pipeline. Thank you!
A PTFE sealing ring will suffice, and the ball valve will be fine.
What's the temperature? There is no problem with using liquid alkali for ball valves.
It looks like a split ball valve! Ball valves are mainly used to transport gas media.
The liquid alkali is not heated, it depends on the ambient temperature, but especially in winter, the valve and flange are all white liquid alkali crystals. Can you guys help me find out what is the reason? Thank you!
Your installation is obviously outdoor. According to your situation, it should be caused by the large annual temperature difference, which causes the thermal expansion and contraction of the gasket, including seasonal leakage caused by the thermal expansion and contraction of the residual liquid that penetrates into the sealing surface. Because in summer, the temperature of the metal surface under direct sunlight can even exceed 100°C. , at this time, the expansion expands the sealing surface of the sealing flange, and leakage occurs due to gaps after shrinkage at low temperatures in winter. Solution: 1. All packing seal gaskets and valve seats are made of ppl high-temperature resistant PTFE material. 2. All bolts, including the bolts on the flange valve body, must use high-strength bolts. 3. Seasonally lock all bolts again.
Thank you to the guys above for your guidance!
There is no problem at all with the 316L PTFE-lined ball valve. In your case, there is either a quality problem with the ball valve or a large temperature difference. The solution is to tighten the middle screw in the morning or evening when the temperature is low. If it still doesn't work, just replace the valve. If conditions permit, you can directly install the nickel 6 valve, which is more expensive. I have been engaged in caustic soda workshop maintenance work for 9 years