CLAMP FOR SUSPENSION OF SUCKER-ROD STRING Russian patent published in 2000 - IPC

FIELD: oil-producing industry, particularly, devices used for suspension of sucker-rod strings in performance of repairs of wells equipped with sucker-rod pumps, regulation of pump stroke, etc. SUBSTANCE: clamp body has mouth for polished rod. Slider in body is installed on one side of mouth. Movable slip is engageable with rod and through wedge joint with slider. Clamp has changeable plates whose working surface is made in compliance with diameter of clamped member of sucker-rod spring. One plate is installed on front side of movable slip. The other plate is installed directly on side opposite to movable slip. Clamp is designed for self-clamping that increases its reliability and convenience in operation. Equipment of clamp with changeable plates made of plastic material provides for clamp versatility and makes it possible to avoid damage to working surface of polished rod and in this way to enhance reliability and service life of casing-head stuffing box. EFFECT: higher efficiency. 2 dwg