| 摘要 |
FIELD: oil and gas industry. ^ SUBSTANCE: invention refers to oil engineering and is duty for conventional pump jack in oil production. It provides lower metal consumption, height overall dimensions, ensures vertical axial stability and ecological safety of the device. The device contains plunger hydraulic cylinder forming under-plunger space and moving it upwards under excess pressure of working liquid and pulling it down under weight of pump rod column when pressure released in under-plunger space. Besides, the device accommodates lift string containing the specified executive section of the hydraulic drive, and working liquid feed pump under excess pressure. According to the invention executive section of the hydraulic drive is provided with central tube supplying working liquid into under-plunger space. As plunger pulled down, this working liquid is ejected through the same tube. Wellstream transportation channel represents annular gap between hydraulic cylinder and lift string. Moreover, vertical axial stability of executive section of the hydraulic drive is ensured with its arrangement on the wellhead below the hanger of downhole equipment. ^ EFFECT: lower metal consumption, height overall dimensions, ensures vertical axial stability and ecological safety of the device. ^ 1 dwg |
