Regarding the oil sealing pressure
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Why is the seal oil pressure at the drive end of a centrifugal pump lower than that at the non-drive end?
Is the pump a multi-stage pump, a two-stage pump, or something else? In two-stage and multi-stage pumps, the pressure in the sealing chambers on the non-driving sides is higher than that on the driving side; therefore, the pressure of the sealing oil is also higher accordingly. In the case of single-stage double-suction pumps, the pressure at both ends is the same.
Thank you for the reply. This pump is a constant-bottom oil pump; it might be a two-stage pump. I would like to ask why the pressure in the non-drive end sealing chamber needs to be a bit higher Is it related to the export and import interfaces?
I asked the experienced worker at the time, and he said it was related to back pressure, but I didn’t understand
This actually has to do with the structure of the pump; it is necessary to examine the pump’s cross-sectional diagram to see where the sealing chambers at both ends are located. Typically, the sealing chamber on the drive side is situated at the pump’s inlet, and the pressure in this chamber is equal to the inlet pressure. The sealing chamber on the non-drive side is located at the inlet of the second impeller, or behind the balance disk or drum in multi-stage pumps, where the pressure is higher than the inlet pressure.