Finding the cause of a damaged mechanical seal

It might be defective in installation, with uneven tightness.

The stationary ring rotates along with the moving ring, and it breaks upon coming into contact with the pin. Looking in the direction shown in Figure 1, does the pump rotate counterclockwise?

I would like to ask under what circumstances does the static ring rotate along with the moving ring?

There are signs of polishing on the surface of the static ring, and it seems to have slightly changed color as well. Dry grinding should occur (that is, insufficient or no liquid in the annular area). This will result in considerable friction, causing the moving ring to rotate the stationary ring as well

The stationary ring and the stationary ring seat are in tight fit; can the moving ring drive the stationary ring to rotate?

You need to know that when two tori stick together, human strength simply isn’t enough to separate them. The friction force of dry friction is very high. It’s not as you might think – the static ring O-ring is press-fitted, so it can’t rotate.

:handshake Thank you for your advice

Was the gap between the static ring and its seat too large when you installed it, which caused the static ring to get distorted when the pump was started?

Is the compression level appropriate? Is it because the shaft alignment of the multi-stage pump isn’t properly adjusted? Is the rubber ring of the static ring suitable?

There are several reasons for the damage to the static ring of a mechanical seal: 1. Idle operation leads to damage to the mechanical seal； 2. Damage to the mechanical seal caused by improper operation by the operator: 3. Damage to the mechanical seal resulting from incorrect installation during its replacement ； 4. Reverse high-speed operation of the pump causes damage to the mechanical seal ； 5. Incorrect selection leads to easy damage of the mechanical seal ； 6. The above are several common reasons why the mechanical seal of a pump is prone to damage. Therefore, when selecting a pump, it is necessary to specify what type of material is being handled, what the temperature is, and what the operating conditions are. Additionally, it is strictly prohibited to run the pump at idle, to allow it to grind dry, or to operate it in reverse at high speed while there is material inside! Our experience shows that the dry running time should not exceed 25 seconds; if it exceeds 25 seconds, the mechanical seal will be damaged.