Why is material flowing out of the emergency cooling water pipeline for the centrifugal pump’s seal?
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This post was last edited by lovestory on 2011-3-15 at 22:37. Today, I suddenly noticed that the temperature of the water coming out of the seal cooling system of a centrifugal pump was quite high (around 50°C). So I increased the supply of cooling water, but the temperature of the water exiting the system remained high. When I closed the cooling water valve, water (which seems to be the material being processed) continued to flow out from the cooling water outlet pipe, and its temperature was still high. After removing the seal from the cooling water inlet pipe, material sprouted out from inside it. What could be the reason for this? Please give me some advice. Thank you!
Reply to 1# Yienuo Zhang: Could the original poster explain in more detail? I’m not quite understanding it. “When the cooling water valve was closed, water (which should be the material) continued to flow out of the cooling water outlet pipe, and the temperature of this water was high.” After removing the cooling water inlet pipe from the pump, material actually sprayed out from it”
Close the valve that supplies cooling water; water is still flowing out from the pump’s cooling water outlet (what should be flowing out is the material, whose properties are similar to those of water). Remove the cooling water inlet pipe from the pump, and the cooling water inlet pipe of the pump starts spraying the material outside. Simply put, the material is leaking out from the inlet and outlet of the mechanical seal cooling water. What could be the reason?
Reply to 3# Yienuo Zhang: The material has leaked into the cooling water chamber, which means there are holes in that chamber; moreover, the medium being transported is corrosive! Meeting this for the first time!
It’s likely that there’s a sand hole on the pump head side; a defect from the casting process caused corrosion and a hole, which led to the medium leaking into the cooling chamber. I’ve indeed encountered this issue before……
On either side of the mechanical seal are cooling water and the material. Typically, the pressure of the cooling water is higher than that of the material on the back side of the impeller; the cooling water serves to cool and lubricate, while also ensuring that only water enters the material and that no material leaks out. The problem, as posed by the original poster, is likely that the mechanical seal is damaged; meanwhile, the pressure of the sealing fluid may be lower than that of the material, which causes the material to leak through the mechanical seal. The poster can check the specified pressure for the cooling water as well as the pressure at the pump inlet, and analyze it
If it’s a dual-machine seal, then it’s the internal seal that’s leaking
Of course, it must be the mechanical seal that’s leaking
With a mechanical seal, such phenomena are 100% caused by a leak in the mechanical seal. Be careful to install the mechanical seal correctly when replacing it
First, replace the machine seal； Second, increasing the flushing pressure