Plunger pump issues
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It’s called a plunger pump, but it isn’t really one; it uses liquid alkali, and the flow rate becomes unstable. When the inlet and outlet check valves are inspected, there are no problems with them. Sometimes, by heating the inlet and outlet check valves as well as the piston area with steam, the flow rate becomes stable again. It’s really strange! ! ! Dear experts, what’s going on here? Those who have been through this, please offer some advice. Thank you~
It is likely that the medium being transported crystallizes easily at room temperature or its viscosity changes, resulting in internal leakage in the inlet and outlet valves of the plunger pump; therefore, heating it with steam resolves the issue
Hello, I also suspected that it was due to viscosity issues before. Later, I measured the viscosity of the liquid caustic in both the raw material tank and at the pump outlet, and the difference was not significant; the viscosities met the requirements specified for use in our company. If crystallization occurs, it shouldn’t happen in this weather; the concentration is 48%
Is it just single-direction alkali injection, or is the alkali reused? When we use single-direction injection, there’s no problem with fresh alkali, but when it’s reused, the phenomenon you mentioned occurs. We are engaged in desulfurization, and when the alkali is reused, there are many impurities present and it becomes more viscous; I’m not sure what’s the case for you
Check what material the ball inside the check valve is made of; if alkali corrodes the ball and causes it to shrink, it will cease to function, and it is possible to choose a different material for the ball. It’s also possible that the ball is stuck in the socket; knocking on it and blowing on it with steam should help
We have encountered similar situations with you before, but it was with diaphragm pumps; there were probably quite a lot of crystalline impurities in the plunger area
Hello, we disassembled the inlet check valve for inspection and found no abnormalities. I now suspect that impurities may be present at the inlet check valve and are causing the issue; now that it has been reinstalled, the flow rate is extremely stable.
One-way alkali injection is used, but the raw material tank has not been in use for a long time; it is likely to contain many impurities.
Hello, we are spring-type check valves
It’s much better when alkali is added in one direction, as the medium remains cleaner. We have a tank for preparing the alkali, equipped with mixing and heating functions, and the pipes are lined with copper for heat retention and insulation; so there are basically no problems. Winters in Shandong are very cold
Not only the check valve needs to be removed, but also the pump head