Patent ID: 7367391

Claim:
A hanger assembly for securing a string of expandable casing to an upper casing, the hanger assembly comprising: a radially expandable housing for securing to an upper end of the expandable casing and locating within a lower portion of the upper casing; an annular radially expandable seal on the housing; and a plurality of lengthwise expandable slips disposed around a circumference of a circularly-shaped portion of the housing, each of the lengthwise expandable slips comprising elongated strips having a run-in position in which each of the lengthwise expandable slips comprise a wave-shape with a peak having at least one gripping element and two valleys disposed on either side of the peak, the expandable housing being radially expandable from the run-in position to a partially expanded position, wherein the peak contacts an inner wall of the upper casing to anchor the expandable casing, and the seal is still spaced from the inner wall of the upper casing to provide a flow path for cement returns, and the expandable housing being further expandable from the partially expanded position to a set position, wherein the peak bites into the inner wall of the upper casing causing the lengthwise expandable slips to become compressed and the seals to seal against the upper casing.