Assembly of a flexible pipe and an end-fitting

Abstract

An assembly of an end-fitting ( ), having an axial extending through opening ( ), with a flexible pressure pipe ( ) which is of a non-bonded structure comprising a number of layers ( ) including an inner carcass ( ) of an interlocking structure made from metallic strips ( ) forming a screwthread, an end part of which extends, in the assembled condition, into the through opening ( ). The assembly comprises an annular holding groove ( ) which is formed in the wall of the through opening ( ), and a lock nut ( ). The metallic strips ( ) form a thread ( ) with windings ( ). When the pipe ( ) is to be assembled with the end-fitting ( ) the carcass ( ) is exposed by initially removing the layers ( ) surrounding the carcass ( ) at the end of the pipe ( ), whereafter the lock nut ( ) is screwed on to the end of the carcass. Finally the carcass ( ) is inserted into the through opening ( ) with the lock nut ( ) placed in the holding groove ( ) formed in the wall of the through opening ( ). In some applications the lock nut ( ) can also be embedded in a casting material (not shown), e.g. epoxy, for fixing the lock nut firmly in the holding groove. The joint between the carcass ( ) of the flexible pressure pipe ( ) and the end-fitting ( ) is a simple and cheap structure and provides a greater resistance to axial tensile loads acting on the carcass ( ) and against unwinding than has been known before.