GB1423728A - Method of producing a fibre reinforced resin pipe - Google Patents

Abstract

1423728 Making pipes SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ BV 9 April 1973 16891/73 Heading F2P A fibre-reinforced resin pipe is made by forming a number of tubular layers individually on a mandrel, one of the layers being a reservoir layer of material impregnated with a flowable and hardenable thermosetting resin and another layer being a constriction layer, which is applied under tension after formation of the reservoir layer, so that the resin is expelled from the latter into a reinforcement layer. In one way of performing the invention, a tape 16 of fibrous material, e.g. of square weave glass fibre, and a strip 17 of reservoir material, e.g. of flexible open-cell polyurethane or natural or synthetic elastomer foam, are wound on to a rotating mandrel 10 from a traverse 12, while strip 17 is being impregnated with a thermosetting resin, e.g. flowable epoxy, formaldehyde or polyester resin, from a spray nozzle or slit, arranged between reel 14 and mandrel 10. On the return run of traverse 12, a further tape (18) of fibrous material is wound, under tension caused by means of an adjustable friction clutch acting on reel 15. Many variations are described, thus, the constricting layer (18) which causes exudation of the resin, instead of remaining as part of the finished pipe, may be an endless band, which is continuously wound on the reservoir layer at one location and wound off at another. In order that the winding may be entirely performed with materials in an externally dry condition, the resin may be introduced between two strips of reservoir material, wound together in face-toface contact.