Patent ID: 7827685
Filing Date: 2010-11-09
Classification: F01D,F05D,F16J,Y10T

Abstract:
1. A method of forming an air seal element constructed and arranged for sealing a static part to a rotating shaft of a gas turbine engine to prevent leakage of cooling air from regions of high pressure to regions of low pressure, comprising a seal edge constructed and arranged to be held in close proximity in use to the rotating shaft, the edge being reinforced by creases extending away from the edge, a distribution of perforations provided above the edge to provide an air pressure differential across the edge as the shaft rotates in relation to the edge and the rotating surface rides upon an enhanced back pressure created by air leakage through the perforations, the method comprising the steps of: folding a length of material backward and forward to form a number of creases and a seal edge constructed and arranged to be in close proximity to a rotating shaft, wherein angles of the folds are selected to determine a desired curvature of the seal edge, and using a sufficient length of material to provide a seal edge at least completely encircling the shaft; and forming the perforations in the seal element above the seal edge, the perforations being constructed and arranged to provide an air pressure differential across the edge as the shaft rotates in relation to the edge and the rotating surface rides upon an enhanced back pressure created by air leakage through the perforations.