The helix seal: Sealing concept and rib design

Abstract The helix seal is a radial shaft seal with enhancements for better sealing performance. A low angular torque is necessary to minimize kinetic energy loss of the shaft. This is achieved by a lubricating oil film, which is a potential source of leakage. To overcome this, the seal has moulded helix ribs to pump any leaked oil back to the sump. The design of these ribs therefore is a critical element in the seal's design. Here, the authors from NOK Corporation present an analytical method of assessing helix rib design.