The pumping fluid is located at the inside diameter of the seal faces. Solids will be thrown into the lapped faces destroying some face materials. Solids will pile up in front of the movable faces, preventing them from compensating for wear. Most seal faces are weak in tension. Poor packaging that allows face damage during shipment and storage.
High speed requires the use of stationary seal designs.
Centrifugal force can open rotating designs above 5000 fpm. The seal is positioned too far from the bearing housing. Lack of a self-aligning feature is causing excessive face movement. A tapered stuffing box can cause face damage. No vent has been provided to vent the stuffing box in a vertical application.