Double-acting, deep-well fluid extraction pump

A double-acting, deep-well fluid extraction pump assembly, comprising a power piston within which an inner conduit, a crescent space, pressure chambers and two manifolds are formed and a pumping piston through which interconnected fluid flow passages extend, set up by:

• (a) an inner tubular piston rod within which the inner conduit extends and around which the crescent space is formed by an outer tubular piston rod, a pair of gland membranes establishing horizontal borders of each manifold through which hydraulic power fluid enters and consecutively pumped fluid exits, and a number of double-acting, lineal, fluid motor pistons individually positioned between a pair of gland membranes to provide an upper pressure chamber of the power piston with a port through which fluid flows from and to the inner conduit and a lower pressure chamber of the power piston with a port through which fluid flows from and to the crescent space and to impart reciprocal fluid flow to the inner conduit and to the crescent space during upward and downward sliding movements of the fluid motor piston;
• and
• (b) a number of gravity-biased poppet-type check valves axially aligned in a central cavity of an upper portion of the pumping piston, except for an interruption by a plug, and interconnected by fluid-flow passages including a first flow path, via which fluid flows from a suction tube through a bottommost poppet-type check valve to a lower pressure chamber of the power piston, formed between bottom of the upper portion of the pumping piston and a gland membrane, and then through a higher poppet-type check valve to the crescent space, and a second flow path, via which fluid flows from the suction tube through a poppet-type check valve that is above the plug to an upper pressure chamber of the power piston, formed between top of the upper portion of the pumping piston and the lowest gland membrane of the power piston, and then through an uppermost poppet-type check valve to the inner conduit;
• whereby when hydraulic power fluid flows through the crescent space and under the fluid motor pistons and forces the power piston and the pumping piston to move upwards, pumped fluid flows into the lower pressure chamber of the power piston and forces the pumping piston to move upwards and to exert pressure on the previously-stored pumped fluid of the upper pressure chamber of the power piston and thereby pumped fluid exits the pumping piston via the inner conduit;
• whereby when hydraulic power fluid flows through the inner conduit and over the fluid motor pistons and forces the power piston and the pumping piston to move downwards, pumped fluid flows into the upper pressure chamber of the power piston and forces the pumping piston to move downwards and to exert pressure on the previously-stored pumped fluid of the lower pressure chamber of the power piston and thereby pumped fluid exits the power piston via the crescent space;
• and
• whereby flow of pumped fluid to the inner conduit is separated from flow of pumped fluid to the crescent space.

A double-acting, deep-well fluid extraction pump comprising:

• (a) a power piston having a tubular casing and housing
• an inner tubular piston rod providing an inner conduit,
• an outer tubular piston rod coaxially extending around and being separated by a crescent space from the inner tubular piston rod,
• gland membranes being permanently joined to the tubular casing and positioned in a slidable relationship with the outer tubular piston rod and dividing the power piston into pressure chambers and into a manifold that is connected via a path to a power control system and via a port to the inner conduit and another manifold that is connected via a path to the power control system and via a port to the crescent space, and
• a number of double-acting, lineal, fluid motor pistons permanently-joined in series to the outer tubular piston rod but positioned in a slidable relationship with the tubular casing, with each fluid motor piston being positioned between an upper pressure chamber of the power piston, topped by an upper gland membrane and connected to the inner conduit through a port, and a lower pressure chamber of the power piston bottomed by a lower gland membrane and connected to the crescent space through a port;
• and
• (b) a pumping piston being housed below and coupled with the power piston, being divided into a lower portion housing a suction tube and an upper portion with which a tubular casing is in a slidable relationship, that extends from bottom of an upper pressure chamber of the power piston, topped by the lowest gland membrane of the power piston, to top of a lower pressure chamber of the power piston, bottomed by a gland membrane which is permanently joined to the tubular casing and which is in a slidable relationship with the lower portion of the pumping piston, and having a number of gravity-biased poppet-type check valves that are interconnected by fluid-flow passages and that are arranged in a central cavity extending along the upper portion of the pumping piston except for an interruption by a plug which divides the poppet-type check valves into two groups.