Method of reeling and unreeling an internally clad metal pipeline

摘要

A method is disclosed for reeling a pipeline having an inner corrosion-resistant metallic liner that is tightly fitted within the pipeline. To minimize or avoid wrinkling of the liner during the reeling or unreeling, a length of the pipeline is internally pressurized by deploying a single sealing pig within the pipeline near to the trailing end of the pipeline and applying pressurized fluid within the pipeline, and then the length of pipeline is reeled onto a storage reel. In the pressurizing process, the length of the pipeline is filled with fluid at an elevated pressure within a range defined by a lower limit of 5 bar.

主权项

1. A method for winding a pipeline onto a reel, the pipeline having an inner corrosion-resistant metallic liner that is tightly fitted within an outer pipe that is less corrosion-resistant, comprising the operations of:
(a) providing a fluid connection between the pipeline and pumping/pressurizing equipment via a manifold mounted on the pipeline; (b) pumping, by means of pressurized fluid, a movable plug along a length of pipeline towards a trailing end to fill the length of pipeline with fluid; (c) locking the plug near the trailing end of the length of pipeline; (d) pressurizing the fluid in the length of the pipeline to an absolute pressure within a range defined by a lower value of 5 bar; (e) connecting a leading end of the pipeline to a reel via the manifold; (f) winding the pipeline onto a reel, while an absolute pressure within the range is maintained within the pipeline; (g) depressurizing the pipeline; (h) unlocking the plug; and (i) joining a further pipeline section to the trailing end followed by repetition of the pumping, locking, pressurizing and winding operations; wherein the absolute pressure in the pipeline is maintained in step (d) by an accumulator connected to the pipeline during the winding operation.