SWABBING MANDREL FOR TUBING STRING Russian patent published in 2015 - IPC E21B43/00 E21B37/00 

FIELD: oil and gas industry.

SUBSTANCE: device includes a metal rod representing a pump rod, a head that is attached by means of a threaded connection to the lower part of the metal rod, a cuff installed on the metal rod with a possibility of being moved along its axis, a cotter pin installed in the metal rod and the head so that unscrewing of the head can be prevented, and a limit stop. The latter has a possibility of being fixed at the pre-set point on the metal rod so that movement of the cuff can be provided in the pre-set range. The limit stop represents a ring with a trapezoidal cross-section; with that, diameter of the ring in the part that is the closest to the head corresponds to the head diameter, and a fluid medium passage is provided in the limit stop.

EFFECT: improving reliability and convenience of operation of a swabbing mandrel.

4 cl, 2 dwg