Patent ID: 9194512
Filing Date: 2015-11-24
Classification: B23K,E21B,F16L,H02G

Abstract:
1. A method of manufacturing coiled tubing from a strip of metal flat plate comprising: welding two or more heat resistant conduits, at least one of which is a heat resistant cable and at least one which is an empty tubular, to the flat plate, the heat resistant conduits being heat resistant for withstanding at least temperatures for annealing of the coiled tubing and the cable; forming the flat plate into a slit tubular having a longitudinal joint; sealing the longitudinal joint by welding to form coiled tubing; annealing the coiled tubing and the one or more conduits at an annealing temperature for an annealing time; and following annealing pumping a secondary conduit into the empty tubular.