WELLHEAD HYDRAULIC DRIVE UNIT

摘要

The present invention provides a wellhead hydraulic drive unit to operate various styles of downhole pumps, which is installed as an integral part of a wellhe ad thereby eliminating the need for a stuffing box. The wellhead hydraulic drive unit comprises a hollow hydraulic cylinder having a piston positioned therein, a hydraulic fluid supply means attached to the hydraulic cylinder for producing reciprocation of the piston within the hydraulic cylinder, a hollow ram means slideably received within the inn er wall of the hydraulic cylinder and connected to the piston for reciprocation in response to the piston; and a production tube means inserted through the ram means for enabling well fluid to be discharged from the well.