Seeking help regarding seal leakage in centrifugal pumps
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I would like to ask fellow sea users: For a centrifugal pump equipped with a single-face mechanical seal (of the standard type with a large spring), leakage occurs from outside the shaft sleeve when the pump is in standby mode, but no leakage occurs when it is running. What could be the reasons for this? Thank you.
In my opinion, it’s likely that when the pump is in standby mode, the temperature inside the pump chamber is low; as a result, the O-ring located under the shaft sleeve wears out, creating a larger gap with the shaft, which leads to leakage. Once it starts running and the temperature rises, does the gap become smaller, which in turn results in no leakage? Could you describe the operating conditions in detail? I’d really like to know as well
After startup, the axial force increases, causing the shaft seal gasket to be pressed tightly! If the mechanical seal leaks when it is in standby mode, it might be due to a problem with the spring’s elasticity; this issue may be resolved after turning it on and off a few times. The shaft seal leak generally needs to be repaired
The elastic force of the spring is too low; once the pump starts operating, the pressure inside the pump exerts a compensating force on the spring, which reduces the leakage from the mechanical seal during pump operation or even eliminates such leakage altogether.
When in use, if the axial pressure is high, the gasket of the shaft sleeve will fail.