3908704 is referenced by 107 patents and cites 7 patents.

The invention is concerned particularly with the production of corrugated tubing made from polytetrafluoroethylene or from the copolymer of tetrafluoroethylene and 5-35 percent of hexafluoropropylene which can be bent on a short radius to any desired shape and will retain its shape with or without substantial springback. In the preferred embodiment the corrugations extending outward from the tube have side walls of unequal length and in close-packed condition the side walls are inclined to the axis at an acute angle, producing a contour called cross-cut saw toothing or oil canning which will permit one corrugation to fold in under an adjoining corrugation in order to make very close bends. The tubing is then heat set in close-packed condition.

Corrugated tubing
Application Number
Publication Number
Application Date
September 12, 1966
Publication Date
September 30, 1975
McCaw Walter J
Clement Ira T
Dressler Goldsmith Clement & Gordon
Penntube Plastics Company
F16L 11/11
F16J 03/04
F16J 03/00
F16L 11/00
F16L 11/11
F16L 11/02
B29C 71/02
B29C 53/30
B29C 53/00
A61F 02/06
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