摘要 |
The present invention includes a subterranean pump assembly (100) in fluid communication with a production zone (150). The assembly includes a body (110) defining a cavity (190) therein and an elastic, collapsible bladder (155) suspended longitudinally within the cavity. The flexible bladder is in one-way communication at a lower end (125) with production fluid (165) from the well and in one-way communication at an upper end (120) with a collection line for transportation of the production fluid to the surface of the well. After the bladder fills with production fluid due to hydrostatic pressure in the well, control fluid in the annular area therearound is pressurised, causing the bladder to collapse. In this manner, production fluid in the bladder is forced upwards through the valve at the upper end thereof and into the collection line. |