Patent ID: 7757764
Filing Date: 2010-07-20
Classification: E21B

Abstract:
1. A method of cementing a casing string in a well, comprising: (a) providing an annular groove in a tubular sub and attaching the sub to a lower portion of a casing string, the sub having an inner diameter that is at least equal to an inner diameter of the casing string, the groove having an inner diameter larger than an inner diameter of the casing string; (b) deploying the casing string and sub in the well; then (c) providing a tubular body with an engaging assembly mounted thereon, pumping the tubular body and engaging assembly down the casing string and anchoring the body to the groove by radially expanding the engaging assembly into the groove relative to a longitudinal axis of the sub; then (d) pumping cement through the body and up an annulus surrounding the casing string, and preventing cement from flowing down the annulus and back through the body into the casing string; and wherein step (d) further comprises: providing the body with a check valve that allows downward flow through the body after the body has anchored to the groove, and which blocks upward flow through the body.