LONG STROKE PUMPING UNIT

摘要

A long stroke pumping unit (1k) includes: a tower (11); a counterweight assembly (10) movable along the tower; a crown (7) mounted atop the tower; a drum (8) supported by the crown and rotatable relative thereto; a belt (9) having a first end connected to the counterweight assembly, extending over the drum, and having a second end connectable to a rod string; and a linear electromagnetic motor (6) for reciprocating the counterweight assembly along the tower. The linear electromagnetic motor includes: a traveler (18a, 18b) mounted to an exterior of the counterweight assembly; and a stator (16a, 16b) extending from a base of the tower to the crown and along a guide rail (17) of the tower. The pumping unit further includes a sensor (15t) for detecting position of the counterweight assembly.