Will the mechanical seal of a centrifugal pump leak when it runs in reverse?
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Will the mechanical seal of a centrifugal pump leak when it runs in reverse?
New ones generally don’t leak, but those that have been in use for a long time may leak.
If there is a Plan11 flushing scheme, leakage is likely to occur. P11 uses the outlet medium for self-flushing and cooling; when it reverses direction, the pressure at the pump outlet is too low, which effectively cuts off the flushing fluid. This often leads to damage to the rotating and stationary rings due to frictional heat
Why should a centrifugal pump be run in reverse? Does running a centrifugal pump in reverse damage it badly?
In that case, 21, 13, and 14 could all be missed
Another example is that the flow rate of the pump driven by the outlet valve is too high
It will leak. Sealing springs are designed according to the pump’s rotation direction; reversing it will inevitably cause the spring to fail and lead to leakage. Furthermore, reversal can cause the impeller nut to loosen or even fall off; in mild cases, it may lead to the loosening of the seals between the impeller and the shaft sleeve, resulting in leakage from the shaft sleeve, while in severe cases the impeller can scrape against the pump body and cause the shaft to break!
If it is a single reed, leakage will occur; whereas with multiple reeds or bellows, leakage generally does not happen. However, prolonged reverse rotation of the centrifugal pump can cause the temperature of the liquid in the pump chamber to rise, leading to vaporization, and ultimately exceeding the compression force of the mechanical seal, resulting in leakage. Moreover, if it is rotated in the reverse direction, the mechanical seal will be damaged due to a lack of fluid – in systems with a flushing mechanism, the mechanical seal usually has a pumping ring.
This post was last edited by Zigong Mechanical Seals on 2017-5-2 at 13:40. The rotating element that transmits power through springs cannot rotate in the reverse direction 【as shown in the figure】. Other structural reversals have no effect on mechanical seals