Patent ID: 8136845

Claim:
A coupling apparatus for coupling free ends of a pair of tubular ducts in flow communication with one another, the free ends of the ducts being separated by an axial gap having a known, approximate axial length, and the ducts adapted to flow a fluid therethrough, the apparatus comprising: a sleeve having a length sufficient to span said axial gap and to overlap portions of said free ends of said ducts when said sleeve is secured to said free ends of said ducts, said sleeve including: a first stretchable ply of material, a non-stretchable ply of material, and a second stretchable ply of material sandwiched together, with the non-stretchable ply of material disposed between the first and second stretchable plies of material, to form a unitary assembly, said non-stretchable ply of material having an axial length approximately equal to the known, approximate axial length of said axial gap to overlay said axial gap, and to overlay substantially a full length of said axial gap, while said sleeve has an inner diameter approximately the same as an outer diameter of said free ends of said ducts so as not to impede flow of said fluid between said free ends of said pair of tubular ducts; said first stretchable ply of material has a first seam, said non-stretchable ply of material has a second seam, and said second stretchable ply of material has a third seam; and wherein said second seam is circumferentially offset from said first seam by about 90 degrees, and said third seam is circumferentially offset from said second seam by about 90 degrees.