High temperature spring seals

A spring seal for sealing in high temperature applications includes a jacket and a spring member disposed within the jacket. The spring member is constructed to control a sealing load or spring rate of the spring seal relative to opposing flanges while the jacket is constructed to provide a sealing surface relative to the opposing flanges. The spring member is manufactured from a cast blade alloy, thereby allowing the spring member to maintain its spring back characteristics at relatively high temperatures of about 1300° F. and greater. Accordingly, the spring member minimizes the formation of a leak path between the spring seal and the opposing flanges. In one embodiment, the spring member is manufactured with a substantially U-shaped cross-section. With such a configuration, the spring seal provides substantially balanced, opposing forces on the jacket to minimize the formation of gaps between the spring seal and the flanges.