Face seal for pump or mixing vessel shaft - has hard seat mounted by graphite backing ring and sealed to associated components by wedge ring

摘要

The rotary mechanical face seal has a seat (12) of hard material, such as sintered silicon carbide or tungsten carbide or tungsten carbide. The seat is made by arranging that only the rubbing face is machined and the remaining surfaces are left rough. The seat is mounted by means of a graphite backing ring (13) which can be of moulded-on expanded graphite powder or tape. It can be sealed to its associated components by a wedge ring (14) also of moulded or compacted graphite, bearing against a rough unmachined face of the seat.