Seal accommodating thermal expansion between adjacent casings in gas turbine engine

Claim 1

In a gas turbine engine having an upstream casing and a downstream casing the improvement comprising: one of said upstream and downstream casings having a cylindrical extension coextensive with and concentrically surrounding a cylindrical portion of the other of said upstream and downstream casings, whereby at the coextensive location there is formed an outer shell, an inner shell and an annular space between said outer shell and said inner shell, said annular space exposed from one side to pressure inside said upstream and downstream casings, and on the second side to external pressure; a circumferential radially extending seal surface extending from one shell of said inner and outer shells toward the other shell of said inner and outer shells, said surface axially facing toward said internal pressure side; a plurality of arcuate seal segments circumferentially arranged within said annular space; each seal segment including an L-shaped section with one leg in sealing contact with said radially extending seal surface and the other leg in sealing contact with said other shell; and locating means for securing each seal segment to said one shell loosely adjacent said seal surface.