Abstract: A centralizer for use in a wellbore includes a body for disposing around a periphery of a downhole tubular. The body has a plurality of bow springs biased toward an expanded position and a pair of end rings connecting the bow springs. The centralizer further includes an indentation or row of indentation segments formed in a surface of and along each bow spring. The indentations or indentation segments are operable to reduce a stiffness of the centralizer as the bow springs move from the expanded position to a restricted position.

Abstract: A shoe for use with a casing or liner string includes: a tubular body; a nose: mounted to an end of the tubular body, and having: a plenum formed therein, a front port extending longitudinally from the plenum to an exterior of the nose, and a side port extending transversely from the plenum to the exterior of the nose; and a valve repeatedly shiftable between a deployment position where the front port is open and the side port is closed and a cleaning position where the front port is closed and the side port is open. The valve shifts to the deployment position in response to forward flow through the shoe being less than a threshold flow rate. The valve shifts to the cleaning position in response to the forward flow through the shoe being greater than the threshold flow rate.

Abstract: A centralizer for use in a wellbore includes a body for disposing around a periphery of a downhole tubular. The body has a plurality of bow springs biased toward an expanded position and a pair of end rings connecting the bow springs. The centralizer further includes an indentation or row of indentation segments formed in a surface of and along each bow spring. The indentations or indentation segments are operable to reduce a stiffness of the centralizer as the bow springs move from the expanded position to a restricted position.

Abstract: A flow-actuated valve for use in a wellbore includes: a body; a poppet movable relative to the body between an open position and a closed position; a spring biasing the poppet toward the closed position; and a shifter having a drogue and a detent engaged with a detent profile of the poppet and a locking receptacle of the body when in an auto-fill mode, thereby keeping the poppet in a partially open position. The valve is operable to shift to a float mode in response to a first flow rate moving the poppet toward the open position to disengage the detent from the locking receptacle and a second flow rate imparting a drag force on the drogue sufficient to disengage the detent from the detent profile. The second flow rate is different than the first flow rate.

Abstract: A stop collar for mounting to a downhole tubular includes: a cylindrical housing having a threaded inner surface and a tapered inner surface; a compressible slip ring having teeth formed in an inner surface thereof and a pair of tapered outer surfaces; a solid cam ring having a tapered inner surface; and a cylindrical bolt having a threaded outer surface. A natural outer diameter of each ring is greater than a minor diameter of the threaded surfaces. Screwing the threaded surfaces of the housing and the bolt is operable to drive the tapered surfaces together, thereby compressing the slip ring such that the teeth engage a periphery of the tubular.

Abstract: A stop collar for mounting to a downhole tubular includes: a cylindrical housing having a threaded inner surface and a tapered inner surface; a compressible slip ring having teeth formed in an inner surface thereof and a pair of tapered outer surfaces; a solid cam ring having a tapered inner surface; and a cylindrical bolt having a threaded outer surface. A natural outer diameter of each ring is greater than a minor diameter of the threaded surfaces. Screwing the threaded surfaces of the housing and the bolt is operable to drive the tapered surfaces together, thereby compressing the slip ring such that the teeth engage a periphery of the tubular.