Patent ID: 9309998
Filing Date: 2016-04-12
CPC Classification: B29C,B29K,F16L

Claim Text:
1. A process for producing a flexible pipe of multilayer structure with unbonded layers effective for conveying a liquid or gas selected from the group consisting of crude oil, natural gas, methanol, and CO 2 at a temperature of at least 130° C., the process comprising: forming a layer by winding a tape helically onto a more internal layer, and simultaneously or subsequently welding an upper sublayer of the tape and a lower sublayer of the tape to one another at an overlap region of no more than about 10% of the width of the tape via introduction of electromagnetic radiation, wherein the tape comprises a plastics molding composition based on olefinic polymer, polyamide, fluoropolymer, polyphenyl sulphone, polyarylene ether ketone, polyphenylene sulphide, or a polyarylene ether ketone/polyphenylene sulphide blend, the portions of the upper sublayer of the tape and the lower sublayer of the tape not welded to one another at the overlap region being no more than frictionally bonded together, wherein the electromagnetic radiation absorption properties of the tape differ across the width of the tape, when helically winding the tape, a more electromagnetic radiation absorbent width of the tape is covered by a more electromagnetic radiation transparent width of the tape, and at least two of the layers of the multilayer structure are not bonded directly or indirectly together.