Patent ID: 6595280
Filing Date: 2003-07-22
Classification: E21B,F04B

Abstract:
A submersible well pumping system comprising:a) an axially elongated housing having a diameter less than the bore hole of the well; b) a plurality of rigid pumping chambers formed in the housing and enclosing pumping fluid and working fluid in a fixed volume; c) flexible diaphragm means dividing each pumping chamber into two sub-chambers thus separating the pumped fluid from the working fluid; d) pump inlet means connecting the pumped fluid sub-chambers and the bore hole of the well; e) pump outlet means connecting the pumped fluid sub-chambers and the surface of the earth; f) inlet check valve means per pumped fluid sub-chamber extending between the pump inlet and each pumped fluid sub-chamber allowing unidirectional flow of pumped fluid from the pump inlet means to the pumped fluid sub-chambers; g) outlet check valve means extending from the pump outlet means to each pumped fluid sub-chamber allowing the unidirectional flow of pumped fluid from the pumped fluid sub-chambers to the pump outlet means; h) a closed hydraulic system filled with working fluid; i) an auxiliary pump circulating working fluid through the closed hydraulic system; j) a two-state main valve engaged to the closed hydraulic system, extending between the auxiliary pump and the working fluid sub-chambers to alternately insert and simultaneously withdraw working fluid to the working fluid subchambers; k) main valve actuation means providing mechanical motion to change the state of the main valve; l) a plurality of control chambers comprising volumes of working fluid and located in the vicinity of matching pumped fluid and working fluid sub-chambers, having rigid boundaries except where separated from the pumped fluid sub-chamber by a flexible diaphragm; m) a plurality of control valves, each connected to the main valve actuation means and to the appropriate working fluid sub-chamber and control chamber; n) means to insure the main valve is completely switched; o) a plurality of control chambers engaged to the control valves; p) a plurality of fluid passageways extending from the auxiliary pump to the main valve, from the main valve to the control valves and from the main valve to the working fluid subchambers; q) prime moving means attached to the auxiliary pump and driving the auxiliary pump; r) a gas purging system comprising a plurality of gas traps, each gas trap further comprising a small orifice connecting a rigid chamber located at the highest point in the working fluid sub-chamber to the working fluid sub-chamber; and s) a relief valve located at the highest point in the rigid chamber, set to open at a pressure slightly higher than the system switch pressure.