APPARATUS OF OIL WELL ROD TYPE PUMP Russian patent published in 1994 - IPC

FIELD: oil industry. SUBSTANCE: one partition is mounted in a cylinder and forms lower and upper chambers. Other partition is set in cavity of a rod. Working body is made as two pistons, connected by a hollow plunger. One of the pistons is mounted in the upper chamber and forms a supporting chamber and a collecting chamber. Another one is mounted in the lower chamber and forms sucking chambers. A hollow pipe is set in cavities of the plunger so as to be capable of communication of the lower sucking chamber with a central canal. The canal is made in the upper piston and communicates with the collecting chamber through radial canals, made in the rod under the partition. The lower piston has a canal, that provides communication of the upper sucking chamber with cavity of the plunger, connected with the supporting chamber by a radial canal, made over the partition. An additional sucking valve is mounted in a side wall of the cylinder from the upper chamber side. A delivering valve is mounted in cavity of the rod over the upper radial hole. One reverse valve is mounted at inlet of a pipe, one more - ar outlet of the canal of the lower piston, two more check valves are mounted at outlets of canal, made in the upper piston. Diameter of the rod is less than diameter of the plunger. EFFECT: apparatus is used in oil or water wells for pumping. 2 cl, 1 dwg