SINGLE CIRCUIT DOUBLE-ACTING PUMP

Removing water from a subterranean formation entails pumping hydraulic oil from a surface-located hydraulic oil pump through a hydraulic oil line to a downhole water pump piston to drive it in a first direction to pump water through a downhole water line to a water chamber of a hydraulic accumulator at the surface. A piston separates the water chamber and an oil chamber and moves to compress the hydraulic oil in the oil chamber of the hydraulic accumulator. The hydraulic oil pump may then pump hydraulic oil into the oil chamber causing the piston to move toward the water chamber, thereby moving water in the downhole water line and resetting the piston in the downhole water pump. A water valve in the downhole water line at the surface may open and release water when the piston in the downhole water pump reaches a predetermined or reset position.

DETAILED DESCRIPTION

Turning now toFIGS. 1-6, a detailed description of the preferred arrangement or arrangements of the present disclosure will be presented. It should be understood that the inventive features and concepts may be manifested in other arrangements and that the scope of the disclosure is not limited to the embodiments described or illustrated.

FIG. 1depicts a water evacuation system10for extracting water from a subterranean location12, such as an oil and gas well, or other well, that traverses a distance from an earthen surface14to a water source16located below earthen surface14. A subterranean water pump18may be located within water source16. A downhole hydraulic line20and a water removal line22may each be connected to the subterranean water pump18. Water removal line22may be connected to a hydraulic accumulator40, which may be part of a pumping unit24located on earthen surface14. Pumping unit24may be a hydraulic pumping unit and may employ a multitude of components to enable functioning of subterranean water pump18and hydraulic accumulator40. Pumping unit24may employ an electric motor26, which may drive or turn hydraulic pump28thereby forcing or pumping hydraulic fluid toward a hydraulic control valve30located in downhole hydraulic line20. A hydraulic pump line32may be valveless and lead from hydraulic pump28and branch into a hydraulic line that leads to hydraulic accumulator40and downhole hydraulic line20. Hydraulic pump line32that leads from hydraulic pump28may be a relatively high pressure hydraulic line that is a conduit that supplies pressurized hydraulic fluid for passage or distribution to downhole water pump18to energize or drive downhole water pump18. Downhole water pump18may have only one downhole hydraulic line20and only one water removal line22that are attached to it and that run between or fluidly link downhole water pump18and earthen surface14.

During a pumping stroke of water pump18, a water pump piston60within water pump18may have high pressure hydraulic fluid forced against a rod-side62of water pump piston60as depicted inFIG. 2. Rod64is connected to water pump piston60and thus, the side of water pump piston60to which rod64is connected is referred to as “rod-side.” Rod side of water pump piston60may also form part of a boundary of a rod side chamber34, which is a reservoir that varies in volume and that houses hydraulic fluid pumped in from downhole hydraulic line20. Force of hydraulic fluid against rod-side62of water pump piston60causes water pump piston60to move upwards, with reference to its normal installation orientation as depicted inFIG. 2, in accordance with arrow66(FIG. 1). As water pump piston60moves upward within piston sleeve68in accordance with arrow66, water within traveling valve chamber70moves upward and into water channel72, which may be vertical or substantially vertical within water pump18. Traveling valve chamber70may be formed within a plunger, which is commonly referred to as a plunger74, that is attached to an opposite end of rod64as water pump piston60; thus, water pump piston60, rod64and plunger74move together as a collective unit during pumping strokes and water drawing strokes of water pump18(FIG. 1). A pumping stroke occurs when water is forced into water removal line22and toward earthen surface14. A water drawing stroke occurs when water is drawn into water chamber114of water pump18when piston60moves in an opposite direction as a pumping stroke of piston60.

Continuing with an explanation of water pump18, water within traveling valve chamber70, water located immediately above plunger74, water within water channel72, water within water channel78, and water located immediately above water pump piston60, is able to be lifted or pumped through water removal line22because ball76seats and seals against ball seat82of plunger74. Water channel72and water channel78permit water to pass around piston chamber80within which water pump piston60resides. Ball seat82and ball76of plunger74are also referred to as a travelling valve because plunger74moves within a sump casing, also known as a standing94. As water pump piston60, rod64and plunger74together translate upwards in accordance with arrow66, water is drawn into bottom sump84of water pump18. More specifically, water is drawn into bottom sump reservoir86when sump ball88lifts from sump ball seat90of standing94. Sump ball88and sump ball seat90of standing94are referred to as a stationary valve. Plunger74fits within standing94to permit movement of plunger74within interior walls of standing94. When plunger74moves away from sump ball valve chamber92within standing94, a volume of sump reservoir86increases while a vacuum is created within sump reservoir86. The vacuum causes water to be drawn from subterranean location12below standing94, past sump ball88and into sump ball valve chamber92and subsequently into sump reservoir86. Upward pumping movement of water pump piston60causes water to move through water removal line22, and with valve54closed during upward movement of water pump piston60during this stroke, water enters water chamber52of hydraulic accumulator40thereby causing floating piston42within hydraulic accumulator40to move upward, which is away from water inlet of hydraulic accumulator40, thereby causing displacement of hydraulic fluid out of hydraulic fluid chamber36of hydraulic accumulator40, subsequently through open accumulator drain line valve106(hydraulic accumulator fill valve100is closed when volume of hydraulic fluid chamber36is decreasing), and into hydraulic fluid tank46.

When downhole hydraulic line20is energized by hydraulic pump28with hydraulic pressure sufficient to generate enough force to cause water pump piston60to move upwards in a pumping stroke that removes water from xxx16, hydraulic fluid is drawn from hydraulic fluid tank46, into hydraulic pump feed line27, through hydraulic pump28, through hydraulic pump line32, through an open downhole hydraulic line valve30and into downhole hydraulic line20to a rod side of water pump piston60of water pump18.

At the same time that downhole hydraulic line valve30permits hydraulic fluid to flow into downhole hydraulic line20, hydraulic fluid is prevented from flowing into hydraulic fluid tank46through hydraulic drain line96because hydraulic drain line valve98is closed. Additionally at the same time, hydraulic fluid is prevented from flowing into hydraulic fluid chamber36of hydraulic accumulator40during upward motion of water pump piston60because hydraulic accumulator fill valve100is also closed, thus preventing pumped hydraulic fluid and associated hydraulic pressure intended for downhole hydraulic line20from escaping into hydraulic accumulator40or into hydraulic accumulator drain line102. Upon water pump piston60moving during a pumping stroke (upward stroke to move water to hydraulic accumulator40), water moves upward toward earthen surface14through water removal line22and into water chamber52of hydraulic accumulator40with water valve54closed. A pumping stroke of water pump piston60occurs from a lowest possible position of piston60within piston chamber80of water pump18, also known as a lowest bottom position, to a highest possible position, also known as a highest top position, of water pump piston60within piston chamber80of water pump18. When piston60reaches its highest top position, which is completion of a pumping stroke, a pressure sensor104located within hydraulic pump line32, such as near hydraulic pump28, senses hydraulic pressure within hydraulic pump line32and causes a control module112to actuate hydraulic drain line valve30to a closed position and to actuate hydraulic accumulator fill valve100to an open position.

During each pumping or upward stroke of water pump piston60of downhole water pump18, floating transfer piston42moves within hydraulic accumulator40causing a progressive increase in the volume of water chamber52and a corresponding progressive decrease in the volume of hydraulic fluid chamber36. Piston42maintains a contact fit against the cylindrical interior wall of hydraulic accumulator40to maintain a leak-proof sealing fit between water chamber52and hydraulic fluid chamber36so that water and hydraulic fluid are always separated and are prevented from mixing. Despite such a leak-proof seal, floating transfer piston42may move when subjected to a force; such as a force caused by hydraulic pressure, such as hydraulic water pressure within water removal line22and water chamber52, or hydraulic oil pressure generated within hydraulic fluid chamber36from hydraulic fluid pumped through hydraulic accumulator hydraulic oil line38from hydraulic pump28. Thus, each upward movement of water pump piston60of water pump18causes floating transfer piston42to move so as to increase the volume of water chamber50with water valve54closed. Also, during movement of floating transfer piston42due to water chamber52filling with water, a volume of hydraulic fluid equal to a volume of hydraulic fluid displaced by movement of floating transfer piston42flows out of hydraulic fluid chamber36and into hydraulic accumulator hydraulic oil line38, through accumulator drain line valve106resident within hydraulic accumulator drain line102and into hydraulic fluid tank46. When hydraulic accumulator drain line valve106is open, hydraulic accumulator fill valve100is closed. Hydraulic accumulator fill valve100is located in a fluid path between hydraulic pump28and hydraulic fluid chamber36of hydraulic accumulator40and is normally closed when hydraulic fluid is flowing into hydraulic fluid tank46during movement of floating transfer piston42due to water filling water chamber52of hydraulic accumulator40.

Thus, with continued reference toFIGS. 1-4, in an exemplary cycle of water evacuation system10, with accumulator drain line valve106open, hydraulic accumulator fill valve100closed, hydraulic drain line valve98closed, water valve54closed, and hydraulic control valve30open, hydraulic pump28pumps hydraulic fluid to rod side chamber34thus pressurizing rod side chamber34. As water pump piston60rises, water that plunger74forces into water channel78and water channel72, which route water around cylinder housing piston60, is forced into water removal line22. More specifically, water pump piston60may force water into water removal line22, which leads in a vertical or generally vertical direction toward earthen surface14.

Because hydraulic pump28operates continuously and thereby continuously draws fluid from hydraulic tank46, upon water pump piston60reaching its upper stroke limit within xxx18, such as when water pump piston60resides adjacent interior cylinder end110, pressure within downhole hydraulic line20and hydraulic pump line32will increase, which pressure sensor104will detect. Upon pressure sensor104sensing an increase in hydraulic pressure at or above a predetermined or threshold pressure within hydraulic pump line32, which may exhibit the same pressure as downhole hydraulic line20, a control module112(FIG. 5) in communication with sensor104causes a series of valve changes to occur. With hydraulic pump28continuing to operate and pump hydraulic fluid, accumulator drain line valve106switches from open to close, hydraulic accumulator fill valve100switches from closed to open, hydraulic drain line valve98switches from closed to open, water valve54switches from open to close, and hydraulic control valve30switches from open to close. Thus, upon valves30,54,98,100, and106changing positions as noted above, hydraulic fluid exiting hydraulic pump28flows only through hydraulic accumulator fill valve100, through hydraulic accumulator hydraulic oil line38and into hydraulic fluid chamber36. With hydraulic fluid flowing into hydraulic fluid chamber36and thus increasing pressure within hydraulic fluid chamber36, floating transfer piston42begins to move within hydraulic accumulator40thereby increasing a volume of hydraulic fluid chamber36and decreasing a volume of water chamber52. With water valve54closed, water pressure builds within water removal line22as hydraulic pressure in hydraulic fluid chamber36increases and floating transfer piston42moving to evacuate water from water chamber52. Increasing water pressure in water chamber52and water removal line22forces water pump piston60downward in accordance with a direction of arrow67, which is also a direction opposite that of a water-pumping stroke as depicted with direction of arrow66.

As depicted inFIG. 3, as water pump piston60moves in accordance with direction of arrow67, water pump piston60is returned back to a position from which a pumping stoke may begin. Because water valve54in water tank filling tube56is closed, water is prevented from exiting through water valve54and permitting water pressure to build within water removal line22and fully act upon water pump piston60as pressure builds within hydraulic fluid chamber36of hydraulic accumulator40. When water pump piston60moves due to increasing force against the non-rod-side of piston60, volume of rod side chamber34decreases and hydraulic fluid is forced into downhole hydraulic line20in a direction that is opposite from the flow direction during a pumping stroke. That is, because of motion of water pump piston60, hydraulic fluid is forced into downhole hydraulic line20, through open hydraulic drain line valve98of hydraulic drain line96and into hydraulic fluid tank46while hydraulic control valve30is closed. That is, hydraulic control valve30is closed at the time of a non-pumping stroke, otherwise known as a return stroke, of water pump piston60to require hydraulic fluid to pass through hydraulic drain line valve98of hydraulic drain line96and into hydraulic fluid tank46. Thus, by reversing the direction of water flow through water removal line22and by reversing the direction of hydraulic fluid flow through downhole hydraulic line20during a return stroke of water pump piston60, water pump piston60may quickly be returned to either a lower position within piston chamber80, or its lowest position within piston chamber80, to begin a new pumping stroke. As an example, the lowest possible position that water pump piston60might achieve before beginning its pumping stroke may be when plunger end surface118resides adjacent to sump reservoir end interior surface120or when surfaces118,120actually contact. When water pump piston60is at its position, such as its lowest possible position, before beginning its return to a water-pumping stroke, water valve54changes from a closed position to an open position to permit water from hydraulic accumulator40and water removal line22to exit through water tank filling tube56and into water repository58. In some cycles, water valve54may only be opened to permit water to exit hydraulic accumulator40and water removal line22into water repository58when water pump piston60is at its lowest position in its cycle, which is before water pump piston60begins its pumping stroke or movement toward interior cylinder end110of piston chamber80.

FIG. 4depicts exemplary positions of floating transfer piston42within hydraulic accumulator40during a pumping stroke of water pump piston60and a subsequent return stroke of water pump piston60during operation of water evacuation system10. When water pump piston60of water pump18begins to move toward water removal line22to force or pump water through water removal line22, and toward and into water chamber52of hydraulic accumulator40, floating transfer piston42initially may be at a position42A, and may begin to move toward position42B throughout such a pumping stroke. Initial position42A may be a position closest to an end23of hydraulic accumulator40that connects to water removal line22. Exactly how far floating transfer piston42may move within hydraulic accumulator40depends upon the size, such as a length and internal volume, of hydraulic accumulator40, and the acceleration, speed and force of water against piston42.

Floating transfer piston42moves upward in accordance with arrow66due to a hydraulic force created during such pumping stroke of water pump piston60. As a result, floating transfer piston42may reach a position42B, as depicted inFIG. 4. Position42B may be a position anywhere between position42A and an end25of hydraulic accumulator40. When water pump piston60reaches its maximum pumping stroke position and pressure sensor104senses an increase in hydraulic pressure that is above a predetermined or threshold pressure limit, control module (FIG. 5) may trigger a switching of valves30,54,98,100and106so that water pump piston60may reverse direction to be reset for continued pumping of water from water source16of subterranean location12, as previously described. Pressure may be used to optimize the cycle time, but pressure measurement is not required. Although floating transfer piston42may be hydraulically forced to position42A from position42B, for example, to cause water pump piston60to return to its position within water pump18such that plunger end surface118is immediately adjacent sump reservoir end interior surface120, water valve54may not necessarily be opened on every pump cycle when water pump piston60is so positioned. Opening of water valve54may be accomplished upon sensing a position of floating transfer piston42. More specifically, sensing a position of floating transfer piston42within hydraulic accumulator40may be accomplished by using a tube122centered longitudinally in hydraulic accumulator40that spans the entire length of the hydraulic accumulator40. The tube may house a sensor coil124, which may communicate with control module112and traverse some length, an entire length, or specific portions of tube122, to detect a magnet126in floating transfer piston42. In this manner the position of floating transfer piston42within hydraulic accumulator40may be known at all times and communicated to control module112. Sensing positions of floating transfer pistons within hydraulic accumulators is known in the art. Water valve54may or may not be opened upon water pump piston60reaching a specific position within piston chamber80of water pump18because opening of water valve54to expel water into water repository58is dependent upon a position of floating transfer piston42within hydraulic accumulator18and not only a position of water pump piston60reaching a specific position within piston chamber80. Such a specific position of water pump piston60may be a position within piston chamber80that is immediately before water pump piston60begins a new pumping stroke. Thus, water pump piston60may be in a position to immediately begin a pumping stroke with plunger end surface118located immediately adjacent to sump reservoir end interior surface120such that no further travel of plunger end surface118toward sump reservoir end interior surface120is possible or effective.

In another example of a specific position of water pump piston60at which water pump piston60is in a position within piston chamber80to begin a new pumping stroke, piston rod-side surface62of water pump piston60may be aligned with an inside diameter of hydraulic line inlet into rod-side chamber34of piston chamber80such that the full diameter or complete cross-sectional area of hydraulic fluid inlet into rod-side chamber34is capable of delivering fluid into rod-side chamber34in an unobstructed delivery by any part of water pump piston60.

In yet another example of a specific position of water pump piston60at which water pump piston60is in a position within piston chamber80to begin a new pumping stroke, piston rod-side surface62of water pump piston60may be aligned with an inside diameter of hydraulic line inlet into rod-side chamber34of piston chamber80such that the full diameter or complete cross-sectional area of hydraulic fluid inlet into rod-side chamber34is capable of delivering fluid into rod-side chamber34in an unobstructed delivery by any part of water pump piston60, and plunger end surface118is located immediately adjacent to sump reservoir end interior surface120such that no further travel of plunger end surface118toward sump reservoir end interior surface120is possible or effective. As previously stated, water valve54may not be opened on every pump cycle, or water valve may be opened on every pump cycle. A pump cycle may be defined as the motion of plunger end surface118moving from an initial position adjacent to sump reservoir end interior surface120to its farthest possible location from sump reservoir end interior surface120, and then returning to the same position adjacent to sump reservoir end interior surface120from which plunger end surface118began.

Turning now toFIG. 6, a detailed description of another embodiment of the present disclosure will be presented.FIG. 6depicts a water evacuation system150for extracting water from a subterranean location12, such as an oil and gas well, or other well, that traverses a distance from an earthen surface14to a water source16located below earthen surface14. As can be seen in a comparison ofFIGS. 1andFIG. 6,FIG. 6shares many of the same components as the apparatus depicted inFIG. 1. One difference, however, is in a backflow mechanism152, which includes water repository154, surface water pump156, water pump draw pipe158, water pump feeder pipe160, water tank filling tube162and water dump valve164.

Water evacuation system150may have subterranean water pump18located within water source16. Downhole hydraulic line20and downhole water removal line22may each be connected to the subterranean water pump18. Downhole water removal line22may be connected to water tank filling tube162, which may be located at earthen surface14(i.e. not subsurface) and which may be part of a pumping unit166located on earthen surface14. Downhole water removal line22may also be part of a backflow mechanism152of pumping unit166. Pumping unit166may be a hydraulic pumping unit and may employ a multitude of components to enable functioning of subterranean water pump18and backflow mechanism152, including surface water pump156. Pumping unit166may employ an electric motor26, which may drive or turn hydraulic pump28thereby forcing or pumping hydraulic fluid into downhole hydraulic line20and into water pump18to energize or drive downhole water pump18. Downhole water pump18may utilize only one downhole hydraulic line20and only one downhole water removal line22for operation. Downhole hydraulic line20and downhole water removal line22run between or fluidly link downhole water pump18and components on earthen surface14. Details of internal components of water pump18are explained above in conjunction withFIGS. 2 and 3.

When downhole hydraulic line20is energized by hydraulic pump28with hydraulic pressure sufficient to generate enough force to cause water pump piston60to move upwards in a pumping stroke that removes water from water source16, hydraulic fluid is drawn from hydraulic fluid tank46, into hydraulic pump feed line27, through hydraulic pump28, through hydraulic pump line32and into downhole hydraulic line20to a rod side of water pump piston60of water pump18. At the same time that hydraulic fluid to flows into downhole hydraulic line20during a water pumping stroke of water pump18, hydraulic fluid is prevented from flowing into hydraulic fluid tank46through hydraulic drain line96because hydraulic drain line valve98is closed. Upon water pump piston60moving during a pumping stroke (upward stroke inFIG. 2), water moves upward toward earthen surface14through downhole water removal line22and into water tank filling tube162with water valve164in water tank filling tube162open. A pumping stroke of water pump piston60occurs from a lowest possible position of piston60within piston chamber80of water pump18, also known as a lowest bottom position, to a highest possible position, also known as a highest top position, of water pump piston60within piston chamber80of water pump18. When piston60reaches its highest top position, which is completion of a pumping stroke, a pressure sensor104located within hydraulic pump line32, such as near hydraulic pump28, senses hydraulic pressure within hydraulic pump line32and causes a control module112to actuate hydraulic drain line valve30to a closed position and to actuate hydraulic accumulator fill valve1500to an open position.

During each pumping or upward stroke of water pump piston60of downhole water pump18, hydraulic pump28pumps hydraulic fluid to rod side chamber34thus pressurizing rod side chamber34. As water pump piston60rises, water that plunger74forces into water channel78and water channel72, which route water around cylinder housing piston60, is forced into downhole water removal line22. More specifically, water pump piston60may force water into downhole water removal line22, which leads in a vertical or generally vertical direction toward earthen surface14.

Because hydraulic pump28continuously operates and draws fluid from hydraulic tank46, upon water pump piston60reaching its upper stroke limit within downhole water pump18, such as when water pump piston60resides adjacent interior cylinder end110, pressure within downhole hydraulic line20and hydraulic pump line32will increase, which pressure sensor104will detect. Pressure within downhole hydraulic line20and hydraulic pump line32could also be measured by a human-readable pressure gage. Upon pressure sensor104or a gage sensing or indicating an increase in hydraulic pressure at or above a predetermined or threshold pressure within hydraulic pump line32, a series of valve changes may occur. With hydraulic pump28continuing to operate and pump hydraulic fluid, hydraulic drain line valve98switches from closed to opened, and water valve164switches from open to close. Additionally, surface water pump156pumps water into water pump feeder pipe160and into downhole water removal line22toward downhole water pump18. Water pressure builds within downhole water removal line22which forces water pump piston60downward in accordance with a direction of arrow67, which is also a direction opposite that of a water-pumping stroke as depicted with direction of arrow66.

As depicted inFIG. 3, as water pump piston60moves in accordance with direction of arrow67, water pump piston60is returned back to a position from which a full and complete pumping stoke may begin. Because water valve164in water tank filling tube162is closed, water is prevented from exiting through water valve164and permits water pressure to build within downhole water removal line22and cause motion of water pump piston60. When water pump piston60moves due to increasing force against the non-rod-side of piston60, hydraulic fluid is forced into downhole hydraulic line20in a direction that is opposite from the flow direction during a pumping stroke. That is, because of motion of water pump piston60, hydraulic fluid is forced into downhole hydraulic line20, through open hydraulic drain line valve98of hydraulic drain line96and into hydraulic fluid tank46. Pump28may continue to pump and discharge hydraulic fluid into hydraulic drain line96and into hydraulic fluid tank46. Thus, during a non-pumping stroke of downhole water pump18hydraulic fluid passes through hydraulic drain line valve98of hydraulic drain line96and into hydraulic fluid tank46. Thus, by reversing the direction of water flow through downhole water removal line22using surface water pump156and by reversing the direction of hydraulic fluid flow through downhole hydraulic line20during a return stroke of water pump piston60, water pump piston60may quickly be returned to either a lower position within piston chamber80, or its lowest position within piston chamber80, to begin a new pumping stroke.

With reference again includingFIGS. 2 and 3, as an example, the lowest possible position that water pump piston60might achieve before beginning its pumping stroke may be when plunger end surface118resides adjacent to sump reservoir end interior surface120or when surfaces118,120actually contact. When water pump piston60is at its position, such as its lowest possible position, before beginning its return to a water-pumping stroke, water valve164changes from an open position to a closed position to permit water from water removal line22to only flow toward downhole water pump18to move piston from the end of a pumping stroke to the beginning of a pumping stroke. A complete cycle or pumping cycle of water pump piston60, may be the greatest linear length of motion possible during a pumping stroke and subsequent return stroke or resetting of water pump piston60to begin a subsequent pumping stroke. For instance, a complete cycle water pump piston60may be the combined motion of rod-side surface62from alignment with surface of tube122to non-rod-side surface of piston60positioned adjacent to interior cylinder end110and then rod-side surface62re-aligning with surface of tube122. Thus, water pump piston60may be in a position to immediately begin a pumping stroke with plunger end surface118located immediately adjacent to sump reservoir end interior surface120such that no further travel of plunger end surface118toward sump reservoir end interior surface120is possible or effective.

In another example of a specific position of water pump piston60at which water pump piston60is in a position within piston chamber80to begin a new pumping stroke, piston rod-side surface62of water pump piston60may be aligned with an inside diameter of hydraulic line inlet into rod-side chamber34of piston chamber80such that the full diameter or complete cross-sectional area of hydraulic fluid inlet into rod-side chamber34is capable of delivering fluid into rod-side chamber34in an unobstructed delivery by any part of water pump piston60. A pump cycle also may be defined as the motion of plunger end surface118moving from an initial position adjacent to sump reservoir end interior surface120to its farthest possible location from sump reservoir end interior surface120, and then returning to the same position adjacent to sump reservoir end interior surface120from which plunger end surface118began.

In yet another example of a specific position of water pump piston60at which water pump piston60is in a position within piston chamber80to begin a new pumping stroke, piston rod-side surface62of water pump piston60may be aligned with an inside diameter of hydraulic line inlet into rod-side chamber34of piston chamber80such that the full diameter or complete cross-sectional area of hydraulic fluid inlet into rod-side chamber34is capable of delivering fluid into rod-side chamber34in an unobstructed delivery by any part of water pump piston60, and plunger end surface118is located immediately adjacent to sump reservoir end interior surface120such that no further travel of plunger end surface118toward sump reservoir end interior surface120is possible or alternatively, effective.

In the above-described embodiments, in closing and opening all valves, and turning on or off all electric pumps, a controller may be employed to automate such processes. Manually causing closing and opening all valves, and turning on or off all electric pumps is also envisioned.