LONG-STROKE HYDRAULIC LIFT SYSTEM HAVING REDUCED HEIGHT

摘要

A lift and method for reciprocating a downhole pump includes an linear actuator, such as a piston-cylinder arrangement, located coaxially above the stuffing box of a well. The linear actuator includes a connecting rod that passes through and seals against the stuffing box, thereby taking the place of the traditional polished rod and allowing the linear actuator to be positioned lower and closer to the well. The connecting rod may be connected to the traditional polished rod below the stuffing box. A stopper may be selectively removed to allow the connecting rod to be pulled clear of the stuffing box while using the polished rod to seal the well, thereby allowing the linear actuator to be removed for maintenance.

主权项

1. A method of reciprocating a pump disposed within a well, said pump connected to a rod string, said rod string including a plurality of sucker rods and terminating at an upper end with a polished rod, said well terminating at the surface of the earth with a stuffing box that is arranged for providing a dynamic seal about said polished rod, the method comprising:
disposing an actuator above and substantially coaxial with said well, said actuator having a cylinder, a piston slideably disposed in said cylinder, a connecting rod connected to said piston, and a gland connected to a lower end of said cylinder and providing a dynamic seal about said connecting rod; connecting said connecting rod to an upper end of said polished rod; and positioning said connecting rod through said stuffing box, said connecting rod being characterized by an outer diameter and finish substantially similar to said polished rod so that said stuffing box is operable to provide a dynamic seal about said connecting rod.