HYDRAULICALLY ASSISTED TUBING EXPANSION

摘要

A method of expanding tubing comprises applying a varying fluid pressure across the wall of the tubing. The variation in pressure may be achieved by varying one or both of the fluid pressure within the tubing and the fluid pressure externally of the tubing. A body of varying volume may be located in a volume of fluid associated with the tubing. Alternatively, the volume of a body of fluid associated with the tubing may be varied by movement of a wall portion defining a boundary of the volume, which wall portion may be associated with an oscillator or a percussive or hammer device. In other embodiments a pressurised fluid source may be provided, and the fluid may be supplied at varying pressure from the source. An increase in pressure within the tubing may be accompanied by a reduction in pressure externally of the tubing.