DEVICE FOR EXPANSION OF CASINGS IN WELL Russian patent published in 2002 - IPC

FIELD: expansion of casings in wells, particularly, articles from shaped pipes with cylindrical ends. SUBSTANCE: device has conical body with central channel and wall hollows located in steps over body length. Installed in hollows perpendicular to device geometric axis are rollers with convex surface and spaced uniformly over body circumference. Dies are installed between rollers and detachably connected with roller axles and locked from longitudinal motions. Rollers and dies in steps are mounted so that dies of next step are located under rollers of previous step. Diameters of circumferences circumscribed round rollers and dies reduce in each step from large base of body conical surface to small one. EFFECT: higher efficiency and serviceability. 3 cl, 3 dwg