Sometimes outside springs get painted by maintenance people. This is more common with dual cartridge seals. The sliding elastomer moves to a dirty service, causing the lapped faces to separate. A discharge recirculation line is aimed at the seal faces or a sliding component restricting its movement. These high velocity solids can erode metal bellows plates causing a drastic failure.
Vibration damping can prevent normal vibration from opening some seal designs.
This is an important consideration in metal bellows seal designs where the elimination of elastomers has made the seal sensitive to vibration. The rotating shaft is not centered in the stuffing box. Misalignment between the pump and its driver. The shaft is bent. The shaft assembly is not dynamically balanced.