Expansion joints

Claim 2

An expansion joint for connecting a pair of adjacent spaced ducts and the like in a fluid tight relationship, said expansion joint comprising a circumferentially continuous belt of flexible material and means for connecting said belt between said spaced ducts in a fluid tight relationship, said belt being composed of a laminated sheet material comprising a layer of stretchable knit metallic wire mesh embedded on both sides with a cured fluoroelastomer sheet, said expansion joint being capable of recoverable elongation in excess of 75 percent and being capable of substantially continuous exposure to temperatures in the order of about 300 to about 400 degrees F. and excursions up to about 600 to about 700 degrees F. without substantial loss of flexibility.

Claim 3

The expansion joint of claim 1 wherein said fluoroelastomer is selected from the group consisting of copolymers of vinylidene fluoride and hexafluoropropylene, terpolymers of vinylidene fluoride, hexafluoropropylene and tetrafluoroethylene, and alternating copolymers of propylene and tetrafluoroethylene.

Claim 4

The expansion joint of claim 1 wherein said belt has a thickness of from about 0.06 to about 0.250 inches.

Claim 5

The expansion joint of claim 1 wherein said wire mesh is provided in two layers, with a pair of opposite edges of said layers being connected.

Claim 6

The expansion joint of claim 1 wherein a layer of insulation is provided on one side of said belt.

Claim 7

The expansion joint of claim 1 wherein said belt is provided with flanges at opposite edges thereof, said flanges being connected to flanges on said ducts.

Claim 8

The expansion joint of claim 1 wherein said fluoroelastomer covers both sides of said wire mesh and is connected through said mesh.

Claim 9

An expansion joint for flexibly connecting a pair of adjacent spaced ducts in a fluid tight relationship, said expansion joint comprising a continuous belt of sheet material in the form of a tube and means adjacent the edges of said tube for connecting said expansion joint between said spaced ducts in a fluid tight relationship, said belt comprising a fluoroelastomer sheet and a reinforcing material embedded in said sheet, said fluoroelastomer being selected from the group consisting of copolymers of vinylidene fluoride and hexafluoropropylene, terpolymers of vinylidene fluoride, hexafluoropropylene and tetrafluoroethylene, and alternating copolymers of propylene and tetrafluoroethylene, said reinforcing material consisting essentially of knitted wire mesh, said belt being capable of recoverable elongation in excess of 75 percent and being capable of exposure to heat at temperatures in the order of about 300 to about 400 degrees F. and excursions up to about 600 to 700 degrees F.

Claim 10

An expansion joint for flexibly connecting a pair of adjacent spaced ducts in a fluid tight relationship, said expansion joint comprising a continuous belt of sheet material in the form of a tube and means adjacent the edges of said tube for connecting said expansion joint between said spaced ducts in a fluid tight relationship, said belt comprising a fluoroelastomer sheet and a reinforcing material embedded in said sheet, said fluoroelastomer being selected from the group consisting of copolymers of vinylidene fluoride and hexafluoropropylene, terpolymers of vinylidene fluoride, hexafluoropropylene and tetrafluoroethylene, and alternating copolymers of propylene and tetrafluoroethylene, said reinforcing material consisting essentially of knitted wire mesh, said belt being capable of recoverable elongation in excess of 75 percent and being capable of exposure to heat at temperatures in the order of about 300 to about 400 degrees F. and excursions up to about 600 to 700 degrees F.

Claim 11

The expansion joint of claim 8 wherein said wire mesh comprises a pair of layers of said mesh, with opposite ends of said layers being connected in the form of a flattened tube.