Flexibox Limited

Neil M Wallace

John P Harrington

Jacobus A Ten Houte De Lange

Centrifugal couplings

In a mechanical seal, a seal face member is compressed by a shrink fitted squeeze ring onto a spigot of a carrier forming one of two seal elements. This arrangement reduces distortion of the seal face and shrouds the seal member from attack by a fluid product in the space. Distortion of the seal face is further discouraged by also shrink fitting the squeeze ring onto the carrier. The squeeze ring circumferentially abuts the face seal member and either radially or circumferentially abuts the carrier to provide structural stability and to shroud the face seal member on three sides leaving only the seal face exposed. The squeeze ring can be arranged internally of the seal face member with the spigot on the carrier arranged externally. In either event the seal face member, usually constructed from carbon is held under radial compression for increased strength.

Mechanical seals

A backup seal for a main seal (not shown) sealing a rotary shaft (10) to a housing (12) comprises a rotary seal element (20) sealed (22) to the shaft (10) and a stationary seal element (16) sealed (18) to the housing (12). The seal elements (16,20) have opposing annular seal surfaces (41,42) surrounding the shaft (10) and these are adapted to be urged together to form a running seal therebetween substantially only by the pressure of fluid product leaking through the main seal should that fail. A second aspect of the invention provides a close fit bush (50) which helps to close the seal faces (41,42) together when the main seal fails and before any leak occurs between them.

Growing community of inventors

Stockport, United Kingdom

Neil M Wallace