Hydraulically assisted tubing expansion

A method of expanding tubing, the method comprising:

• applying a varying fluid pressure to tubing having an internal volume, the varying fluid pressure serving at least in part to increase said volume;
• and
• advancing a mechanical device through the tubing to occupy said increased volume.

An apparatus for expanding tubing downhole, the apparatus comprising:

• a pulse generator configured to generate and apply a varying fluid pressure to the tubing such that the tubing is expanded, and
• at least one seal for isolating a portion of tubing to be expanded from ambient fluid, said at least one seal being adapted to permit a degree of leakage thereacross.

An apparatus for expanding tubing downhole, the apparatus comprising:

• pressurizing system for applying a varying fluid pressure to the tubing;
• and
• an expansion cone adapted to retain expansion induced by elevated fluid pressure, the expansion cone includes a plurality of fluid outlets on a sloped surface thereof for communicating pressurized fluid from the pressuring system to an inner diameter of the tubing.

A method of expanding tubing, the method comprising:

• applying a varying fluid pressure to the tubing, wherein a portion of tubing to be expanded is at least partially isolated from ambient fluid by at least one seal, and a varying pressure differential is maintained across the at least one seal, and wherein the at least one seal is arranged to provide for a degree of leakage thereacross and lubricates the at least one seal;
• and
• producing a pressure pulse, and an associated elevated fluid pressure, which then decays as leakage occurs across the seal.

An apparatus for expanding tubing downhole, the apparatus comprising:

• a pressurizing system configured to apply a varying fluid pressure to the tubing such that the tubing is expanded;
• and
• at least one first seal member disposed proximate an end of the pressurizing system and at least one second seal member disposed proximate another end of the pressurizing system, wherein the seal members are configured to isolate a portion of tubing to be expanded from ambient fluid, wherein each seal member is configured to leak.

An apparatus for expanding tubing downhole, the apparatus comprising:

• a pressurizing system configured to apply a varying fluid pressure to the tubing such that the tubing is expanded, wherein the pressurizing system comprises a member for increasing the pressure within the tubing while reducing the pressure externally of the tubing;
• and
• at least one first seal member disposed proximate an end of the pressurizing system and at least one second seal member disposed proximate another end of the pressurizing system, wherein the seal members are configured to isolate a portion of tubing to be expanded from ambient fluid.