Analysis on centrifugal pump leakage

What should we do if our centrifugal pump leaks

1. Leakage during installation and static test 

If the leak is not serious, it is most probably caused by seal ring problems of dynamic ring or static ring, while serious leaks indicate problems between the friction pairs of the two rings. After primary observation on the amount of leakage and judgment on the point of leakage, you can turn the pump with hand and observe the change of leakage amount. If the leakage doesn’t change obviously, then the problem must be in static and dynamic ring, friction pairs and the seal ring of the dynamic ring. Maybe the seal ring of static ring has become ineffective. Besides, it is also possible for the existence of leakage channels.

2. Leakage during test run

After static test on the mechanical seal of a centrifugal pump, the centrifugal force generated when the pump runs at high speed will hinder the leakage of fluid. Therefore, despite of ineffective seal in shaft and end cap, most leakage are caused by the damages to the friction pairs of dynamic ring and static ring. In most cases, you need to dismantle the friction pairs, change for a new one and reassemble it. 

3. Sudden leakage in normal operation 

If a centrifugal pump leaks suddenly during operation, it is most probably caused by tremendous change of working conditions or inappropriate operation or maintenance.  If the pump is exhausted, or holds pressure for rather a long time, or suffers from cavitation, the seal will be broken. If the practical output of the pump decreases, it will leave a large amount of fluids circulating inside the pump with heat accumulated simultaneously. That will vaporize the fluids and lead the seal to lose efficiency. If the pump has been idle for a long time, and you didn’t turn it with hand before starting it, the friction pair will be adhesive and tear the the surface of seal. If the medium begins to contain more corrosive, polymerism and gummy materials, or the environmental temperature changes sharply, the seal will also break. 

Faced with all the above kinds of leakage, we should find out a solution respectively, either change the seal or repair it. We should not mend it casually so as to make the centrifugal pump barely work for a longer time, and overhaul it until a more serious problem occurs.

Leak again?

Still leaking?

Come on,

Change for a shield pump, a magnetic pump for good.