Steel pipe used for transport of fluids under high pressure, has outer corrosion-proof protective sheath including plastic layer and crack stopper zone formed by wrapping bandage made of fiber material, around pipe

摘要

The steel pipe (1) has an outer corrosion preventive protective sheath (2) including a plastic material surface layer and a crack stopper zone (3). The stopper is formed by a bandage wrapped around pipe and made of high-strength fiber material embedded in a compacted matrix of thermo-setting or thermoplastic plastic. The bandage has wound layers joined to one another via a matrix, by welding and gluing. The crack stopper zone extends over a portion of the length of the pipe. The bandage has thickness of 10-15 mm and has at least 20 wound layers. Independent claims are also included for the following: (a) Process of making the pipe with a crack stopper zone; (b) Crack stopper zone; (c) Process of protecting pipe against propagation of cracks