Closed system hydraulic expander

• Main Authors: MAGUIRE PATRICK G, TRAN KHAI
• Format: Patent
• Language: English
• Published: 11.09.2003
• Edition: 7
• Subjects: EARTH DRILLING; EARTH DRILLING, e.g. DEEP DRILLING; FIXED CONSTRUCTIONS; MINING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR ASLURRY OF MINERALS FROM WELLS

The present invention provides an apparatus and method for expanding a first tubular against a second tubular. In one aspect, an expander tool includes a mandrel coupled to a spline assembly such that an annular space is formed between the same. Seals are placed between the mandrel and the spline assembly to retain a fluid in the annular space. The fluid may be used to actuate one or more expander members disposed on the spline assembly. The spline assembly is movably connected to a housing, which is coupled to a torque anchor. In operation, the mandrel is rotated, which, in turn, rotates the expander members. Rotation of the mandrel also causes the spline assembly to extend axially, thereby pulling a first seal closer to a second seal. As a result, the pressure in the annular space rises due to the compression of the fluid in the annular space. The rise in pressure extends the expander members into contact with the first tubular and expands the first tubular against the second tubular.