Abstract: A stop collar and a centralizer assembly including the stop collar are provided. The collar includes a first portion, and a second portion coupled with the first portion such that the first and second portions are slidable one relative to the other along a longitudinal axis of the collar. The collar is axially expandable by sliding the first portion relative to the second portion. The collar also includes an anchor coupled with the second portion. The anchor defines one or more anchor windows extending therethrough and configured to expose a portion of a tubular when the tubular is received through the collar. The anchor is configured to bear on an anchoring material received radially inwards through the one or more anchor windows. The anchor does not force the anchoring material into engagement with the tubular when the tubular is received through the collar, the anchoring material being coupled with the tubular.

Abstract: A bow-spring centralizer (6) includes bow springs (34), moving collars (20) secured to each end of each bow spring, and interlocked stop collars (10). Extendable collars (8) may each be formed of a moving collar (20) movably interlocked with a stop collar (10). The centralizer (6) may be formed from a tube cut using a laser to create two extendable collars coupled by bow springs. Each extendable collar may include heads (12) integrally formed on extensions (26) protruding from a collar (stop collar or moving collar). The heads may be generally rectangular, arrow, or teardrop-shaped head or some other shape. Each head may be slidably captured within a chamber (24) on the interlocked collar (moving collar or stop collar). The extensions of each interlocked tubular member define the outer walls of the chamber in which a head of the interlocked tubular member is slidably captured.

Abstract: A bow-spring centralizer (6) includes bow springs (34), moving collars (20) secured to each end of each bow spring, and interlocked stop collars (10). Extendable collars (8) may each be formed of a moving collar (20) movably interlocked with a stop collar (10). The centralizer (6) may be formed from a tube cut using a laser to create two extendable collars coupled by bow springs. Each extendable collar may include heads (12) integrally formed on extensions (26) protruding from a collar (stop collar or moving collar). The heads may be generally rectangular, arrow, or teardrop-shaped head or some other shape. Each head may be slidably captured within a chamber (24) on the interlocked collar (moving collar or stop collar). The extensions of each interlocked tubular member define the outer walls of the chamber in which a head of the interlocked tubular member is slidably captured.

Abstract: A bow-spring centralizer includes a center assembly having a plurality of bow springs and a pair of generally tubular moving collars secured one to each end of each bow spring, the center assembly formed intermediate a pair of generally tubular stop collars. Each moving collar/stop collar combination forms an interlocking and axially extendable collar. The centralizer is formed from a single tube. The tube is cut using a laser according to a cut pattern that creates interlocked stop collar/moving collar combinations that are rotatably locked but axially movable one relative to the other. Each of the interlocked stop collars and moving collars includes a plurality of circumferentially spaced heads, each head integrally formed on one of a plurality of circumferentially spaced extensions protruding from the stop collar or moving collar. The heads may have a variety of projected shapes, such as a rectangular, arrow or a teardrop shaped.

Abstract: A bow-spring centralizer includes a center assembly having a plurality of bow springs and a pair of generally tubular moving collars secured one to each end of each bow spring, the center assembly formed intermediate a pair of generally tubular stop collars. Each moving collar/stop collar combination forms an interlocking and axially extendable collar. The centralizer is formed from a single tube. The tube is cut using a laser according to a cut pattern that creates interlocked stop collar/moving collar combinations that are rotatably locked but axially movable one relative to the other. Each of the interlocked stop collars and moving collars includes a plurality of circumferentially spaced heads, each head integrally formed on one of a plurality of circumferentially spaced extensions protruding from the stop collar or moving collar. The heads may have a variety of projected shapes, such as a rectangular, arrow or a teardrop shaped.

Abstract: A centralizer for laterally positioning a pipe in an opening larger in diameter than an opening through which the centralizer may freely pass is disclosed. The centralizer includes a plurality of helically shaped spring blades affixed at each end thereof to a slip collar. The slip collars are adapted to slide and rotate about the exterior surface of the pipe. A retaining device is disposed axially between the slip collars and is adapted to limit axial motion of the slip collars. One embodiment of the retaining device is a sleeve which is adapted to be affixed to the exterior surface of the pipe at a selected axial position.

Abstract: A centralizer for laterally positioning a pipe in an opening larger in diameter than an opening through which the centralizer may freely pass is disclosed. The centralizer includes a plurality of helically shaped spring blades affixed at each end thereof to a slip collar. The slip collars are adapted to slide and rotate about the exterior surface of the pipe. The retaining sleeve is disposed axially between the slip collars, the retaining sleeve and is adapted to be affixed to the pipe so as to limit axial motion of the slip collars.