DEVICE FOR EXPANSION OF PIPES IN WELL Russian patent published in 2010 - IPC E21B29/10 

FIELD: oil and gas production.

SUBSTANCE: device comprises hollow rod with coupling and nipple threads at the ends, arranged with the possibility of rotation at the middle part of rod, case with windows, in which rolls are arranged at the angle to rod axis, interacting with rod and arranged in the form of cylinders, which are equipped with radial faces in lower part. The middle part of rod is arranged in the form of cone narrowing downwards. The case is arranged with the possibility of limited axial displacement relative to the middle part of rod. Hollow rod above narrowing down cone is equipped with outside piston, inserted with the possibility of axial displacement downwards in hydraulic cylinder, which is connected to case on top with the possibility of rotation. Inside hydraulic cylinder there is bore arranged for fixator, spring-loaded towards outside and installed above the piston in rod. Between rod and hydraulic cylinder there is a pusher tightly installed with the possibility of longitudinal displacement downwards and interaction with fixator for its inside pressing. Cavity of hydraulic cylinder above the pusher is communicated with central channel of hollow rod.

EFFECT: simplified design, increased reliability, lower accident rate.

2 dwg