US Patent 7124827 Expandable whipstock anchor assembly

A whipstock assembly includes a tubular anchor 36 which is expanded into engagement with the casing string 8, and a tubular expander 24 which is forcibly moved into the tubular anchor to expand the tubular anchor downhole into secure engagement with the casing string. The tubular anchor and tubular expander remain downhole. An orientation sleeve 18 at the upper end of the expander 24 includes an orientation surface 20. A whipstock 70 engages the sleeve 18 to orient the whipstock face for diverting a tool into a hole in the side of the casing string. Once the whipstock 70 is removed from the well, the orientation sleeve may receive a sealing nipple 130 at the lower end of a production tubing string.