Is the pump outlet pressure too high, and is the mechanical seal leaking?
Thread Content
Recently, I encountered an issue with a hot water pump where the mechanical seal was leaking. The normal pressure is around 6 MPa, and the current does not exceed the rated value. Where can I find information on the pressure that the mechanical seal can withstand? Is the pressure indicated on the nameplate of the centrifugal pump the same as the pressure for the mechanical seal?
No! One can only find the manufacturer’s samples or books related to sealing by looking up the standard models of mechanical seals! Take a photo and I’ll check it for you!
Another thing to keep in mind is that the pressure in the sealed chamber is not equal to the pressure at the pump outlet – remember this! !
The pressure in the sealed chamber can be consulted with the sealing manufacturer. Anyway, a leak in the mechanical seal isn’t necessarily caused by high pressure, right?
What was said on the fourth floor is correct; there is a common formula stating that the pressure in the sealed chamber equals one-third of the pump’s outlet pressure plus the pump’s inlet pressure. For specific values, it is recommended to consult the manufacturer
On the nameplate of your pump, the head is only 60 m, and the outlet pressure is not 6 MPa
How is it calculated? ? ? Please let me know; thank you very much. However, the outlet pressure of our regular circulation water pumps is around 6.2 MPa
The pump outlet pressure is 0.6 MPa, which can be achieved by standard mechanical seals; the medium is circulating water, which is relatively clean, so ordinary material O-rings will suffice. Cause analysis: 1. No shaft rotation was performed before startup, resulting in dry friction damage to the sealing surfaces due to prolonged contact without lubrication. 2. There are impurities near the sealing surface, which enter the sealing surface during startup and cause damage to it.
The outlet pressure can be calculated as: head * fluid density. The outlet pressure of your pump can be roughly calculated as: 60m*1g/cm3=0.6MPa