Method of treating a pipe and product produced thereby

Claim 2

In a pipe made of a metal which is subject to ductile fracture propagation in a predetermined direction as a result of carrying fluid under pressure, the pipe having means for preventing said ductile fracture propagation, and said preventing means including a reinforcing wrapping on the pipe, the improvement comprising: said reinforcing wrapping extending substantially the entire length of the pipe and including a plurality of continuous, high strength nonmetallic fibers wrapped helically around the pipe under a limited tension which is less than a wrapping tension which would cause a prestress in the pipe, said fibers being parallel to one another, said fibers weighing less than half as much as a ductile fracture propagation preventing means made of steel and having an equal ductile fracture propagation preventing capability, said fibers being non-corrodible to protect the pipe from the atmosphere, soil and chemicals, and said fibers being electrically non-conductive to protect the pipe from gallvanic and cathodic corrosion; and said reinforcing wrapping further including a curable viscous matrix encapsulating said fibers to define a continuous composite material, said curable viscous matrix being deformable to absorb the energy of impacts.

Claim 3

The pipe of claim 1, further comprising adhesive holding said fibers to the pipe.

Claim 4

The pipe of claim 1 wherein said fibers are glass fibers.

Claim 5

The pipe of claim 3 wherein each of said fibers has a diameter less than 0.001 inch.

Claim 6

The pipe of claim 3 wherein said glass fibers are made of E type fiberglass.

Claim 7

The pipe of claim 1, further comprising means for bonding the wrapping to the pipe.

Claim 8

The pipe of claim 6 wherein said bonding means is the curable viscous matrix.

Claim 9

In a method of increasing the ductile fracture propagation resistance of a pipe made of a metal which is subject to ductile fracture propagation as a result of carrying fluid under pressure by helically wrapping the pipe with a high tensile strength material, the improvement comprising: encapsulating a plurality of continuous, high strength nonmetallic fibers in a curable viscous material, and wrapping said fibers substantially along the entire length of the pipe under a limited tension which is less than a tension which would cause a prestress in the pipe to a thickness sufficient to define a means for preventing the ductile fracture propagation, wherein said fibers weigh less than half as much as a ductile fracture propagation preventing means made of steel and having an equal ductile fracture propagation preventing capability, said fibers are non-corrodible to protect the pipe from the atmosphere, soil and chemicals, said fibers are electrically non-conductive to protect the pipe from galvanic and cathodic corrosion, and said curable viscous material is deformable to absorb the energy of impacts.

Claim 10

In a method of increasing the ductile fracture propagation resistance of a pipe made of a metal which is subject to ductile fracture propagation as a result of carrying fluid under pressure by helically wrapping the pipe with a high tensile strength material, the improvement comprising: encapsulating a plurality of continuous, high strength nonmetallic fibers in a curable viscous material, and wrapping said fibers substantially along the entire length of the pipe under a limited tension which is less than a tension which would cause a prestress in the pipe to a thickness sufficient to define a means for preventing the ductile fracture propagation, wherein said fibers weigh less than half as much as a ductile fracture propagation preventing means made of steel and having an equal ductile fracture propagation preventing capability, said fibers are non-corrodible to protect the pipe from the atmosphere, soil and chemicals, said fibers are electrically non-conductive to protect the pipe from galvanic and cathodic corrosion, and said curable viscous material is deformable to absorb the energy of impacts.

Claim 11

The method of claim 8, further comprising, prior to the step of wrapping: coating the pipe with a hot viscous material.

Claim 12

The method of claim 9, wherein the step of encapsulating comprises: pre-impregnating said fibers with additional viscous material and drying the additional viscous material prior to the step of wrapping, wherein the wrapping is performed while said hot viscous material is hot.

Claim 13

The method of claim 9, further comprising: winding a wrapping of protective material around the pipe over said fibers.

Claim 14

The method of claim 8, further comprising: curing said viscous material.

Claim 15

The method of claim 8, wherein the step of encapsulating includes: pre-impregnating said fibers with viscous material, and drying said viscous material to form a web of said fibers impregnated with said viscous material, and the method further comprises applying an adhesive to one surface of said web, wherein the step of wrapping is performed by placing in contact with the pipe the surface of said web having the adhesive.

Claim 16

In a pipeline carrying fluid under pressure including pipe made of a metal which is subject to ductile fracture propagation in a predetermined direction as a result of carrying said fluid under pressure, the pipe having means for preventing said ductile fracture propagation, and said preventing means including a reinforcing wrapping on the pipe, the improvement comprising: said reinforcing wrapping extending substantially the entire length of the pipe and including a plurality of continuous, high strength nonmetallic fibers wrapped helically around the pipe under a limited tension which is less than a wrapping tension which would cause a prestress in the pipe, said fibers being parallel to one another, said fibers weighing less than half as much as a ductile fracture propagation preventing means made of steel and having an equal ductile fracture propagation preventing capability, said fibers being non-corrodible to protect the pipe from the atmosphere, soil and chemicals, and said fibers being electrically non-conductive to protect the pipe from galvanic and cathodic corrosion; and said reinforcing wrapping further including a curable viscous matrix encapsulating said fibers to define a continuous composite material, said curable viscous matrix being deformable to absorb the energy of impacts.

Claim 17

In a pipeline carrying fluid under pressure including pipe made of a metal which is subject to ductile fracture propagation in a predetermined direction as a result of carrying said fluid under pressure, the pipe having means for preventing said ductile fracture propagation, and said preventing means including a reinforcing wrapping on the pipe, the improvement comprising: said reinforcing wrapping extending substantially the entire length of the pipe and including a plurality of continuous, high strength nonmetallic fibers wrapped helically around the pipe under a limited tension which is less than a wrapping tension which would cause a prestress in the pipe, said fibers being parallel to one another, said fibers weighing less than half as much as a ductile fracture propagation preventing means made of steel and having an equal ductile fracture propagation preventing capability, said fibers being non-corrodible to protect the pipe from the atmosphere, soil and chemicals, and said fibers being electrically non-conductive to protect the pipe from galvanic and cathodic corrosion; and said reinforcing wrapping further including a curable viscous matrix encapsulating said fibers to define a continuous composite material, said curable viscous matrix being deformable to absorb the energy of impacts.