ROD PUMP UNIT Russian patent published in 2015 - IPC F04B47/02 

FIELD: oil and gas industry.

SUBSTANCE: pump unit contains string of the pump pipes and rods, lock support, cylinder with installed one above another stages with different diameters. On the string of the pump rods two hollow plungers are suspended, they are connected coaxially and movably located inside the cylinder, they have small and large diameter with suction and discharge valves. The suction valve is installed in the large diameter plunger, its cavity is connected with the cylinder cavity by means of the holes. The weight is connected with the bottom end of the large diameter plunger. The lock support has insert-scraper. The top part of the cylinder has toroidal weights. In the bottom end of the small diameter plunger the discharge valve box is installed with diameter exceeding this plunger diameter. The maximum distance from top of the valve box to place of the cylinder stages connection exceeds stroke of the plungers. The bottom part of the large diameter plunger the leaks compensation valve is provided. The toroidal weights are provided with rubber sealing rings, their seat is made with increased cleanness. Above the toroidal weights on the external surface of the cylinder the spring-loaded clamps are installed in form of the isoscales triangle, its top looks upward.

EFFECT: complete operability of the pump, exclusion of the mechanical admixtures ingress in the clearance between the pump wall and internal wall of the lock support.

1 dwg