PLAN53 pressure issue
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Regarding the pressure issue with PLAN53: it is said that the pressure in PLAN53 should be at least 1–2 bar higher than the pressure in the shaft seal chamber. But how is the pressure in the shaft seal chamber determined? I have a high-speed pump with a head of 560 m and a medium density of 0.89; it’s difficult to determine the pressure at the center of the impeller. I guess it could be calculated as (560 * 0.89) = 50 bar, but the maximum reading on the pressure gauge on the buffer tank is only 21 bar. I would appreciate some guidance from those who know more about this. Thank you very much. How does the pressure change as one moves radially from the center of the impeller? Is it approximately proportional to the radius? This post was last edited by liulang on 2008-2-22 at 16:54
In my humble opinion, the pressure in the sealed chamber is only slightly higher than the inlet pressure, due to its connection to the balance tube; moreover, the pump’s operating point is not necessarily at the most optimal position on its performance curve.
The pressure in the sealed chamber is generally lower than the outlet pressure of the pump; therefore, as long as the pump is operating properly, the pressure reading you see is normal. If you are concerned, you can install a pressure gauge in the sealed chamber.
The foreigners’ method for calculating the pressure in a sealed chamber is one-third of the head pressure plus the inlet pressure; you can add an additional 1 kilogram to this value for your tank. Additionally, the book “Questions and Answers on Practical Mechanical Sealing Technology” that you mentioned upstairs contains detailed answers. It doesn’t discuss the pressure in the sealing chamber of multi-stage pumps. I personally don’t agree with the foreigners’ view; it seems to me that the pressure in the sealing chamber should be around half of the pump’s head pressure Why don’t you install a pressure gauge at that sealed chamber to check?