Unbalance Seals

Rubber Bellow Mechanical Seal

Elastomer bellow performs the dual role of spring force and secondary seal, reducing the seal to fewer moving parts
Unbalanced face design keeps construction simple and cost-effective for lower-pressure duty
No coil spring exposed to the process fluid, avoiding spring clogging in mildly contaminated media
Bellow flexibility accommodates minor shaft misalignment and axial movement without loss of sealing contact
Compact, single-piece rotating assembly simplifies fitting on standard pump shafts
Economical construction suited to high-volume, general-purpose pump applications
Available in multiple elastomer grades to match common water, chemical, and general fluid services

PRODUCT DESCRIPTION

A Simple, Economical Seal for General Duty Pumps

Installing a rubber bellow seal is straightforward — the pre-assembled rotating unit is pushed onto the shaft to the specified working length, with the elastomer bellow itself providing the closing force, so there's no separate spring to compress or align. Because the bellow also handles the sealing function against the shaft, fewer components need to be checked during fitment compared to spring-loaded designs. This seal earns its place in general-purpose pump applications — domestic water pumps, small process pumps, and equipment where operating conditions stay within moderate pressure and temperature limits. Its simplicity and lower cost make it a practical default choice wherever the fluid and duty conditions don't demand the pressure handling of a balanced or metal spring design. For complete step-by-step installation instructions and torque specifications, refer to our detailed installation guide on the blog.

TECHNICAL SPECIFICATIONS