Patent ID: 8328160

Claim:
A seal comprising: an annular jacket including a first annular pocket and a second annular pocket; a restrictor disposed in the first annular pocket and capable of restricting shrinkage of the first annular pocket to a predetermined diameter range, if the seal is exposed to a temperature within a predetermined temperature range; and a spring energizer disposed in the second annular pocket and configured to supply a force against the annular jacket to maintain the seal against a contact surface; wherein the restrictor comprises a first material and the annular jacket comprises a second material, wherein the first material has a coefficient of thermal expansion that is less than the second material; and wherein the restrictor has an outer surface that is contoured to correspond to a shape of an inner surface defining the first annular pocket, and wherein a radius of the restrictor and a radius of the first annular pocket are substantially equal, such that when the seal is exposed to a reduced temperature, the restrictor prevents the first annular pocket from shrinking to a greater extent than the restrictor.