Centrifugal pumps for dependable service in the process industries.

Eastern Centrichem pumps utilize mechanical seals exclusively on all models. Mechanical seals are the preferred sealing method in most applications, and offer many advantages over conventional packed stuffing boxes:
 

Eastern pumps are equipped with Type 21^® and Type 9^® seals to cover the widest range of services. These seals are dimensionally interchangeable. They operate in the same manner, using spring tension to keep their stationary and rotating faces in contact.

Primary sealing is accomplished by interaction of the lapped stationary and rotating faces. Secondary sealing occurs at the shaft by means of a tight fitting bellows in the Type 21^® design, or a PTFE wedge in the Type 9^® arrangement. The final sealing point occurs at the static seat by means of either an elastomeric o-ring, or a PTFE seat ring.

The Type 9^® seal is designed for demanding applications. The head is fixed to the shaft by anti-rotation pins, or set screws, and utilizes a PTFE wedge between the seal ring and shaft. The wedge improves sealing and extends a wide range of chemical compatibility. All metal components of the seal are either 316SS or Hastelloy C. The rotary face is either chemical grade carbon or PTFE and the seat is silicon carbide. The Type 9^® seal is also available in a double configuration for more demanding or hazardous applications.