PD two-bearing housings are designed for two sealing solutions:
Table 1 provides an overview of the properties and suitability of each sealing solution. This information should be used as a guideline, which cannot substitute for testing the seal in its application.
Housings in the PDN 3 and PDR series have felt strips, which are mounted in a groove in the cover. At circumferential speeds above 4 m/s, a small gap forms between the felt and the seal counterface.
The outboard V-ring seals (for all housing series) provide additional protection against contaminants. They can accommodate circumferential speeds up to 7 m/s.
PD housings are supplied with seals but the seals can also be ordered separately.