FACILITY FOR EXPANDING PIPES IN WELL Russian patent published in 2009 - IPC E21B29/10 

FIELD: mining.

SUBSTANCE: facility consists of case with central channel, coupling and nipple ends for connection with well equipment and with lengthwise grooves wherein rollers with spherical surface are installed; rollers are arranged uniformly around circumference and in step-by step manner on axes perpendicular to case axis, axes are secured in separator equipped with openings for rollers and made spring-loaded downward; lengthwise movement of separator relative to case is limited with upper and lower stops. Diametres of circumferences around rollers in each step decrease downright. The case is made stepped with extension on top and is designed to interact with the separator and rollers, when the separator moves up. The internal openings of the rollers for axes are made with bigger diametre relative to corresponding axes. The lower stop is made in form of a cylinder and is designed to limited traveling up relative to the case, a ring extension of which is made in form of a piston inserted into the cylinder. Internal space between the cylinder and the piston is communicated with the central channel of the case.

EFFECT: extended sphere of application, simplified design, and reduced costs.

4 dwg