Patent ID: 7516796
Filing Date: 2009-04-14
Classification: E21B,F04B

Abstract:
1. A pumping assembly for elevating liquid through a well having a riser for channeling liquid, a discharge device for removal of liquid from the riser, a piston device for elevating liquid toward the discharge device and including an actuating rod, the actuating rod formed of a flexible material enabling it to be coiled prior to installation, a piston valve unit disposed at a first end of the riser and drivably connected to the actuating rod, and a stationary valve unit disposed at the second end of the riser, adjacent the piston valve unit and operable to remain in a substantially fixed position relative to the riser during movement of the piston valve unit, comprising: the riser being a continuous flexible pipe formed of a material capable of being coiled prior to installation, and then when installed in an elongated generally vertical orientation, capable of forming an essentially straight section with essentially no coil memory so as to substantially avoid any wear by the movement of the unitary actuating rod therewithin; and wherein the piston valve unit has an outer diameter that is greater than an inner diameter of the riser.