Abstract: An apparatus for expanding tubular elements includes a tool body, an axially compressible expansion body mounted on the tool body such that the outer surface of the expansion body is substantially the same outer diameter as that of the tool body, and means for axially compressing the expansion body such that its outer surface is expanded beyond the outer diameter of the tool body.

Abstract: A power transmission system for use with downhole equipment in a borehole includes a power source that is positioned at the surface providing a DC power supply, a downhole DC/DC converter and a two-conductor cable connecting the power source and the downhole DC/DC converter. The power transmission system receives the DC voltage supply as an input and provides an output DC supply at a different voltage to the DC power supply for provision to the downhole equipment.

Abstract: A tubular element can be expanded using an expander tool that includes a flexible sleeve having an outer diameter less than or equal to the inner diameter of the tubular element, a cone expander section on which the sleeve is mounted and an elongate mandrel. The cone expander section includes a first cone having a first narrow end that fits inside the sleeve and that increases in diameter from the first narrow end to a maximum at a base that is greater than the inner diameter of the sleeve but less than the inner diameter of the tubular element. The expander tool can be positioned at a predetermined location in the tubular element, fixed in place, and the expander section can be urged through the sleeve to expand the sleeve and thus the tubular element.

Abstract: A method for expanding a tubular in a wellbore uses an expansion apparatus that includes an expansion body disposed on a tool body. The expansion apparatus is positioned in the tubular. The method further includes compressing the expansion body such that an outer surface radially expands the tubular permanently and axially translating the compressed body within the tubular.