Wedge-shaped seal for flanged joints

Claim 2

A flanged joint for joining the abutting ends of two cylindrical case structures, wherein the improvement comprises: a pair of outwardly convergent sidewalls, one on each of said cylindrical case ends forming a circumferentially extending groove between the case structures; a seal ring having a substantially wedge-shaped cross section disposed within said groove; wherein said seal ring is slidable in the outward direction along the convergent sidewalls of the groove in response to increasing temperature causing a compressive sealing force against the wedge-shaped cross section of the seal ring.

Claim 3

The flanged joint of claim 1 wherein the cross section of the seal ring has a length L and wherein the seal means moves outwardly relative to the case structures a distance greater than one-tenth L for a difference in temperature of one hundred degrees Fahrenheit (100° F.) between the seal means and the average temperature of the cylindrical case structures.

Claim 4

The flanged joint of claim 1 wherein the exteriors of the case structures are disposed in a fluid and cooled by convection and radiation.

Claim 5

The flanged joint of claim 1 wherein the coefficient of thermal expansion of the seal means is greater than the coefficient of thermal expansion of the cylindrical case.

Claim 6

The flanged joint of claim 1 wherein an angle θ is the acute angle between the convergent sidewalls and the angle lies in a range between twenty degrees and forty degrees (20°≦θ≦40°) and wherein the cross section of the seal means has a tip region, a first surface extending inwardly from the tip region, a second surface extending inwardly from the tip region, the second surface being angled with respect to the first surface at an acute angle θ' which lies in a range between twenty degrees and forty degrees (20°≦θ'≦40°).

Claim 7

The flanged joint of claim 5 wherein the seal ring has an axis of symmetry A, the inward portion of the seal ring is at a distance R o from the axis of symmetry A, the cross section of the seal ring has a radially oriented length L, a base dimension b, and is formed of two arms extending inwardly from the tip region, which diverge inwardly wherein the ratio of R o to the length L lies in the range of seventy-five to one hundred seventy (75≦R o /L≦170), and the ratio of the length L to the base dimension b is greater than or equal to one and one-half and less than or equal to three and one-half (1.5≦L/b≦3.0).

Claim 8

The stator structure of claim 5 wherein the base dimension has a value b u in the uninstalled condition, a value b i in the installed condition and the value b u is greater than the value b i (b u >b i ).

Claim 9

For an axial flow rotary machine of the type having an annular flow path for hot working medium gases bounded by a first stator structure and a second stator structure wherein the second stator structure is spaced radially from the first stator structure and has flanges extending circumferentially in abutting contact, an improved stator structure which comprises: a first flange, a second flange spaced from the first flange leaving a groove therebetween extending circumferentially about the flanges which is constricted in the outward direction and is in gas communication with the flow path, a seal ring having a wedge-shaped cross section extending circumferentially in the groove, the cross section having a base b which is adapted to engage the flanges, the seal means being adapted to be otherwise unrestricted against outward movement in the groove, wherein the wedge-shaped seal means is driven outwardly in the constricting groove by thermal expansion to compress the base of the seal means causing a sealing force between the seal means and the flanges.

Claim 10

For an axial flow rotary machine of the type having an annular flow path for hot working medium gases bounded by a first stator structure and a second stator structure wherein the second stator structure is spaced radially from the first stator structure and has flanges extending circumferentially in abutting contact, an improved stator structure which comprises: a first flange, a second flange spaced from the first flange leaving a groove therebetween extending circumferentially about the flanges which is constricted in the outward direction and is in gas communication with the flow path, a seal ring having a wedge-shaped cross section extending circumferentially in the groove, the cross section having a base b which is adapted to engage the flanges, the seal means being adapted to be otherwise unrestricted against outward movement in the groove, wherein the wedge-shaped seal means is driven outwardly in the constricting groove by thermal expansion to compress the base of the seal means causing a sealing force between the seal means and the flanges.

Claim 11

In an axial flow rotary machine of the type having circumferentially extending flanges spaced apart to form a groove which adapts the flanges to receive a seal ring, the improvement which comprises: a seal ring which extends circumferentially about an axis of symmetry, the seal ring having a wedge-shaped radial cross section formed of a tip region and a pair of diverging arms extending inwardly from the tip region and diverging inwardly one from the other at an acute angle, wherein each radial arm has a surface and an acute angle θ' is the angle between the surfaces, wherein each radial arm is spaced a distance R o from the axis A and the wedge-shaped cross section has a radially oriented length L and a base dimension b; and wherein the ratio of the distance R o to the length L is in a range of about seventy-five to about one hundred seventy (75≦R o /L≦170), the ratio of the length L to the base dimension b is in a range of one and one-half to three and one-half (1.5≦L/b u ≦3.5), and the acute angle θ' lies in a range of about twenty degrees to forty degrees.

Claim 12

In an axial flow rotary machine of the type having circumferentially extending flanges spaced apart to form a groove which adapts the flanges to receive a seal ring, the improvement which comprises: a seal ring which extends circumferentially about an axis of symmetry, the seal ring having a wedge-shaped radial cross section formed of a tip region and a pair of diverging arms extending inwardly from the tip region and diverging inwardly one from the other at an acute angle, wherein each radial arm has a surface and an acute angle θ' is the angle between the surfaces, wherein each radial arm is spaced a distance R o from the axis A and the wedge-shaped cross section has a radially oriented length L and a base dimension b; and wherein the ratio of the distance R o to the length L is in a range of about seventy-five to about one hundred seventy (75≦R o /L≦170), the ratio of the length L to the base dimension b is in a range of one and one-half to three and one-half (1.5≦L/b u ≦3.5), and the acute angle θ' lies in a range of about twenty degrees to forty degrees.