RADIAL SEAL AND METHOD OF MAKING

A dynamic radial seal includes a rigid casing. The seal also includes an elastomeric casing positioned interior of and bonded to the rigid casing. The elastomeric casing has an axial spring member which extends radially inwardly from and axially along the rigid casing. The axial spring member includes a neck portion which extends from the elastomeric casing and a seal attachment portion that is attached to the neck portion and has a bonding surface. The seal also includes a pre-stressed fluoropolymer seal which has a bonding surface and a sealing surface. A bond joins the bonding surface of the pre-stressed fluoropolymer seal to the bonding surface of the seal attachment portion. The seal attachment portion of the spring member is operative to provide sealing contact of the fluoropolymer seal along the entirety of its sealing surface when engaged with a mating surface of a shaft. The fluoropolymer seal may be formed from PTFE and may include a groove or grooves formed in the sealing surface to enhance the sealing performance of the seal. The elastomeric casing may also incorporate a static seal or temporary dynamic seal to facilitate in-process testing or dirt exclusion, as well as one or more additional dirt exclusion features to protect the fluoropolymer seal from damage caused by environmental contaminants during the use of the seal.