Systems and Methods for a Gas-Driven Compressor

This application claims the benefit of U.S. Provisional Application No. 63/635,538, filed Apr. 17, 2024, and U.S. Provisional Application No. 63/635,541, filed Apr. 17, 2024, each of which are hereby incorporated by reference in their entirety.

Fluid systems, including pipelines and vessels, can store, transport, or otherwise dispense fluids, including pressurized gasses and liquids. Fluid control systems, such as valves and regulators, can be used to regulate fluid flow within fluid systems.

According to one aspect of the present disclosure, a gas-driven compressor system can include a compressor body defining a first piston cavity, a second piston cavity, and a shuttle valve cavity. The system can include a low pressure port in fluid communication with the first piston cavity, via the shuttle valve cavity, to vent the first piston cavity. A high pressure port can be in fluid communication with the first piston cavity, via the shuttle valve cavity, to provide pressurized inlet flow to the first piston cavity. The system can include a compressor inlet in fluid communication with the second piston cavity and a compressor outlet in fluid communication with the second piston cavity. A shuttle valve can be movable between a first position and a second position within the shuttle valve cavity. The system can include a piston having a first head portion movable within the first piston cavity by the pressurized inlet flow, and a second head portion movable within the second piston cavity by the movement of the first head portion within the first piston cavity to compress a fluid in the second piston cavity. The piston can fluidly couple a signal flow from the high pressure port selectively to a first side or a second side of the shuttle valve cavity, depending on a position of the piston, to selectively direct the pressurized inlet flow to the first piston cavity on, respectively, a first side or a second side of the first head portion of the piston to power reciprocating movement of the piston.

In some examples, the piston can be configured to move in a first direction to draw the fluid into the second piston cavity and in a second direction to compress fluid within the second piston cavity.

In some examples, the piston can define a first groove and a second groove arranged to fluidly couple the signal flow from the high pressure port selectively to the first side or the second side of the shuttle valve cavity.

In some examples, the first groove can be aligned with a first shuttle valve signal line when the first head portion of the piston is in a first position in the first piston cavity, and the second groove can be aligned with a second shuttle valve signal line when the first head portion of the piston is in a second position in the first piston cavity.

In some examples, the first groove can be spaced axially from the second groove along the piston and the high pressure port can be in communication with the piston along a first inlet signal line arranged to pressurize the first groove when the first head portion of the piston is at a first end of the first piston cavity, and a second inlet signal line arranged to pressurize the second groove when the first head portion of the piston is at a second end of the first piston cavity.

In some examples, the first and second grooves can be included on the second head portion of the piston.

In some examples, the system can further include a lever that couples the first head portion to the second head portion.

In some examples, the first head portion of the piston can separate the first piston cavity into a first volume and a second volume. The shuttle valve in the first position can provide the pressurized inlet flow to the first volume and vent the second volume to the lower pressure port, to move the piston in a first direction. The shuttle valve in the second position can provide the pressurized inlet flow to the second volume and vent the first volume to the lower pressure port, to move the piston in a second, opposite direction.

According to another aspect of the present disclosure, a method of compressing a fluid using a process gas driven compressor can include providing a high pressure port of a compressor body in communication with a first pressure, and providing a low pressure port of the compressor body in communication with a second pressure. The method can include moving a first piston with reciprocating movement within a first piston cavity, by moving a shuttle valve in response to a pressure differential between the high pressure port and the low pressure port, the movement of the shuttle valve selectively directing pressurized fluid from the high pressure port to opposite sides of the first piston within the first piston cavity, dependent on a position of a piston assembly that includes the first piston. The movement of the first piston can move a second piston of the piston assembly with reciprocating movement in a second piston cavity to compress a fluid within the second piston cavity.

In some examples, the method can include aligning a first circumferential groove of the piston assembly with a first shuttle valve signal line when the piston assembly is in a first position, to direct the pressurized fluid from the high pressure port to a first side of the shuttle valve, to move the shuttle valve from a first position to a second position, and aligning a second circumferential groove of the piston assembly with a second shuttle valve signal line when the piston assembly is in the second position, to direct high pressure fluid to a second side of the shuttle valve to move the shuttle valve from the second position back to the first position.

In some examples, the method can include discharging the compressed fluid from the second piston cavity, through a compressor outlet port, when the compressed fluid reaches a predetermined threshold pressure.

In some examples, the method can include selectively blocking, with the piston assembly, fluid connection between the high pressure port and shuttle valve signal lines during the reciprocating movement of the first and second pistons.

In some examples, drawing fluid into the second piston cavity can include drawing fluid through an inlet port and a first check valve into the second piston cavity during movement of the piston from the first position to the second position.

In some examples, the fluid compressed in the second piston cavity can be further compressed in a second stage compression by the reciprocating movement of the piston assembly.

In some examples, the reciprocating movement of the piston assembly can direct the compressed fluid from the second piston cavity to a third piston cavity to be compressed by the reciprocating movement of the piston assembly.

According to yet another aspect of the present disclosure, a gas-driven compressor system can include a high pressure port, a low pressure port, and a piston assembly. The piston assembly can include a first piston movable within a first piston cavity in response to a pressure differential between the high pressure port and the lower pressure port, and a second piston moveable within a second piston cavity by movement of the first piston, to compress a fluid in the second piston cavity. The system can include a shuttle valve movable between a first position and a second position in response to the pressure differential between the high pressure port and the low pressure port to cause reciprocating movement of the piston assembly by selectively directing pressurized fluid from the high pressure port to opposite sides of the first piston, dependent on a position of the piston assembly.

In some examples, the system can include a lever mechanically coupled between the first piston and the second position to multiply a force applied by the first piston to the second piston.

In some examples, the shuttle valve can include extensions at opposing ends that extend into corresponding extensions of a shuttle valve cavity to selectively block flow from one or more signal lines into the shuttle valve cavity.

In some examples, the second piston can include a first diaphragm, and a second diaphragm secured together by a piston rod.

In some examples, the first diaphragm can form a first chamber including an inlet port and an outlet port, and the second diaphragm can form a second chamber including a port open to the atmosphere.

The following discussion is presented to enable a person skilled in the art to make and use embodiments of the invention. Given the benefit of this disclosure, various modifications to the illustrated embodiments will be readily apparent to those skilled in the art, and the principles herein can be applied to other embodiments and applications without departing from embodiments of the invention. Thus, embodiments of the invention are not intended to be limited to embodiments shown, but are to be accorded the widest scope consistent with the principles and features disclosed herein.

The following detailed description is to be read with reference to the figures, in which like elements in different figures have like reference numerals. The figures, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of embodiments of the invention. Skilled artisans will recognize the examples provided herein have many useful alternatives and fall within the scope of embodiments of the invention.

Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings.

As briefly described above, some natural gas products, such as valves and electronic regulators, use low pressure gas to operate. In use, some applications of valves and regulators require venting to atmosphere (e.g., auto resetting spring open regulators). With conventional valves and regulators, one challenge is the required low-pressure gas is at a lower pressure than the lowest pressure in the system and cannot be re-injected into the line. One method is to use low pressure, compressed air to operate these products. This requires some amount of gas compression infrastructure. In remote locations, this can be a challenge. Alternatively, process media can be reduced to the appropriate level then exhausted once it has been utilized. Venting process media to the atmosphere can be unfavorable for a variety of reasons, including negative environmental factors.

Aspects of the present disclosure can address these and other drawbacks of conventional operations of valves and regulators. For example, some implementations of the present disclosure provide a process gas driven compressor. The compressor can repressurize low pressure process gas and inject it back into the system (e.g., pipeline) after use. In particular, examples of the present disclosure can provide a compressor that uses process media to drive a piston of the compressor and generate pressurized fluid that can be reinjected back into the system. For example, the compressor may pressurize process fluid by moving the piston linearly back and forth to compress fluid within a piston cylinder. In some examples, incorporation of a second stage in the compression system can increase output pressure compared to a single-stage compression system.

In some examples, the compressor system includes a compressor body with first and second piston cavities that receive portions of a piston. The head of the piston separates the first cavity into first and second volumes. The system includes high and low pressure inlets connected to respective pressure lines, with transfer lines directing pressurized fluid to the first or second volumes based on shuttle valve orientation and correspondingly venting the other volume to the low pressure inlet. In some examples, the shuttle valve controls fluid flow direction. The shuttle valve moves via high pressure fluid supplied through shuttle valve signal lines, which direct fluid to either side of the shuttle valve depending on a current state of the compressor to control movement of the shuttle valve.

In some examples, a second piston cavity includes an inlet port with a first check valve permitting one-way fluid flow in, and an outlet port with a second check valve permitting one-way fluid flow out. This arrangement permits fluid compression as the piston moves.

In some examples, during use, the piston moves through a series of stages. For example, in a first stage, the piston and shuttle valve are in first positions. High pressure fluid enters the first volume through the first transfer line, while the second volume is vented to lower pressure through the second transfer line. When the piston is in the first position, a first circumferential groove in the piston shaft (or other feature) aligns with the high pressure line and first shuttle valve signal line, allowing high pressure fluid to flow to the first side of the shuttle valve to move the shuttle valve.

In a second stage, the shuttle valve moves to a second position (e.g., moved by pressure, as above), redirecting high pressure fluid to the second volume and venting the first volume to lower pressure. This initiates piston movement (e.g., a third stage), which begins drawing fluid into the second piston cavity through the inlet port.

In a fourth stage, a second circumferential groove of the piston shaft (or other feature) aligns with the high pressure line and second shuttle valve signal line, directing high pressure fluid to the second side of the shuttle valve to move the shuttle valve towards the first position.

In a fifth stage, the shuttle valve returns to the first position, redirecting high pressure fluid to the first volume and venting the second volume to lower pressure. This causes the piston to move towards the first position, compressing fluid in the second piston cavity until it reaches sufficient pressure to exit through the second check valve and outlet port.

In some examples, the system may utilize a lever to connect a first piston to a second piston in order to provide a mechanical advantage to generate higher output pressure from low differential input pressure. In other examples, other systems for mechanical advantage can also or alternatively be used (e.g., providing a larger acting surface areas on the first piston than on the second piston, etc.).

In some examples, the compressor system may be a two-stage compressor system. For example, movement of a piston in a first direction can cause a first stage compression (e.g., in the second piston cavity, as described above). This first-stage compressed fluid can be routed to another piston cavity (e.g., similar to the second piston cavity, as described above) and then further compressed by movement of the piston (e.g., in a second direction). In some examples, the shuttle valve may include extensions with radial passageways to control fluid flow while preventing pressure bleed.

illustrate an example of a compressor system(e.g., a process fluid driven compressor system). The compressor systemmay be in the form of a process fluid driven compressor including a compressor bodydefining a first piston cavityand a second piston cavity. In some example, the first and second piston cavities,may each receive a portion of a piston(e.g., a main piston). For example, a first headof the pistonmay translate within the first piston cavity, while a second head (e.g., narrower shaft)of the piston may translate within the second piston cavity. In some examples, the headof the pistonmay have a larger diameter than the shaftof the piston, or other differently sized pistons or piston heads can be provided. Correspondingly, the first piston cavitymay have a larger diameter than the second piston cavity.

In some examples, the headof the pistonmay separate the first piston cavityinto a first volumeand a second volume. Correspondingly, to actuate (e.g., move) the pistonwithin the first and second piston cavities,, varying pressures may be applied to the headof the piston(e.g., via the influx of high pressure fluid into the first or second piston cavities, and corresponding venting of the other). In some examples, in order to provide high/low pressure fluid to the system, the bodymay include a high pressure port (e.g., inlet)and a low pressure port (e.g., inlet). In some examples, one or more high pressure lines(or other inlet flow paths) can be in communication with the high pressure inlet. Correspondingly, one or more low pressure lines(or other inlet flow paths) can be in communication with the low pressure inlet.

In some examples, depending on an orientation of a shuttle valve, fluid from the high pressure linesmay pass into either the first volumeor the second volumevia either a first transfer lineor a second transfer line, and likewise for fluid vented from the volumes,to the low pressure lines. Thus, in some examples, based on the orientation of the shuttle valve, the direction of travel of the pistonmay be controlled (e.g., via alternating flow of high pressure fluid into either the first volumeor the second volume).

In some examples, in addition to the piston, the systemmay include a shuttle valve, which may be housed within a shuttle cavity, separate from the first and second piston cavities,. In some examples, the shuttle valvemay be moveable within the shuttle cavityvia high pressure fluid from the high pressure inlet. For example, the shuttle cavitymay receive high pressure fluid from the high pressure inletvia one or more shuttle valve signal lines. For example, a first shuttle valve signal linemay apply high pressure fluid signal to a first side of the shuttle valve(e.g. to move the shuttle valvein a first direction), while a second shuttle valve signal linemay apply high pressure fluid signal to a second side of the shuttle valve(e.g., to move the shuttle valvein a second, opposite direction). As further detailed below, depending on the position of the shuttle valve, lands and grooves (or other features) on the shuttle valvecan cause selective pressurization and venting of the first piston cavityto drive reciprocating movement of the piston.

In some examples, in order to facilitate fluid flow into and out of the second piston cavity, the compressor systemmay include an inlet port(or other compressor inlet) and an outlet port(or other compressor outlet). In some examples, the inlet portmay include a first check valve(e.g., a suction valve), which may permit one-way flow of fluid into the second piston cavity. Correspondingly, the outlet portmay include a second check valve(e.g., a discharge valve), which may permit one-way flow of fluid out of the second piston cavity. For example, the inlet portand corresponding check valvemay permit the inflow of low pressure fluid into the second piston cavityduring movement of the pistonin a first direction. Correspondingly, the outlet portand corresponding check valvemay permit the outflow of high pressure fluid out of the second piston cavityas the fluid is compressed due to movement of the pistonin a second, opposite direction. In general, the check valvemay be configured to permit the outlet of compressed fluid (e.g., to the outlet port) once the compressed fluid reaches a predetermined threshold pressure.

With continued reference to, an example process for compressing fluid (e.g., process fluid from a pipeline, air, etc.) using the compressor systemwill be described. For example,illustrates a first stage of a fluid compression process. In the first stage, each of the pistonand the shuttle valveare arranged in respective first positions,. That is, with respect to the orientation shown in, each of the pistonand the shuttle valveare arranged the right side of their respective cavities,. In some examples, for the pistonto reach the first position, the high pressure inletmay supply high pressure fluid from the high pressure linethrough the first transfer lineto the first volume. Correspondingly, the low pressure inletmay vent the second volumeto low pressure via the low pressure lineand the second transfer line.

In some examples, due to the orientation of the shuttle valvein the first position, the first transfer lineis configured as a high pressure line (e.g., is fluidically connected to the high pressure line). However, as the shuttle valve movesto a second position, the first transfer linemay transition to a low pressure line (e.g., fluidically connected to the low pressure line).

Generally, features on the pistonor the bodycan cooperate to selectively route signal pressure to opposite sides of the shuttle valve, depending on a position of the piston. In some examples, when the pistonis in the first position, a first circumferential grooveformed in the shaftof the pistonmay be aligned with the high pressure lineand a first shuttle valve signal line. Thus, high pressure fluid from the high pressure linemay flow through the first shuttle valve signal lineand to a first side of the shuttle valve. Correspondingly, the shuttle valvemay begin to actuate within the shuttle valve cavityin the direction shown by arrow.

Turning now to, a second stage of the fluid compression process is shown. In the second stage, the pistonremains in the first position, while the shuttle valvehas moved to a second position. With the shuttle valvein the second position, high pressure fluid from the high pressure lineis now in fluid communication with the second volumevia the second transfer line. Correspondingly, the low pressure inletmay vent the first volumeto low pressure via the low pressure lineand the first transfer line. As a result, the pistonmay begin to move in the direction shown by arrow(sec, e.g.,), which may begin to draw fluid into the second piston cavityvia the inlet port(e.g., through the first check valve). Further, during movement of the piston in the direction shown by arrow, the fluid connection between the high pressure lineand the shuttle valve signal lines,may be blocked by the shaftof the piston.

As shown in, at a third stage of the fluid compression process, the pistonmay be in a second position, while the shuttle valveremains in the second position. When the pistonis in the second position, a second circumferential grooveformed in the shaftof the pistonmay be aligned with the high pressure lineand the second shuttle valve signal line. Thus, high pressure fluid from the high pressure linemay flow through the second shuttle valve signal lineand to a second side of the shuttle valve. Correspondingly, the shuttle valvemay begin to actuate within the shuttle valve cavityin the direction shown by arrow(e.g., towards the first position).

As shown in, at a fourth stage of the fluid compression process, the pistonmay be in the second position, while the shuttle valvehas returned to the first position. As mentioned previously, when the shuttle valveis in the first position, the high pressure inletmay supply high pressure fluid from the high pressure linethrough the first transfer lineto the first volume. Correspondingly, the low pressure inletmay vent the second volumeto low pressure via the low pressure lineand the second transfer lineto the second volume. As a result, the pistonmay begin to move in the direction shown by arrow(e.g., towards the first position, see, e.g.,). In some examples, as the pistonmoves in the direction shown by arrow, the fluid within the second piston cavitymay be compressed, which may pressurize the fluid. In some examples, once the fluid reaches a predetermined pressure, the fluid may pass out of the second check valveand out of the outlet port.

In some examples, a discharge flangecan direct pressure back into the body. In general, the discharge flangecan be used to build up a steady pressure for release, rather than an oscillating pressure. However, in some examples, the discharge flangemay not be included.

illustrate an example of a process gas driven compressor system, which is an example implementation of the process gas driven compressor systemas described in. As will be recognized, the systemshares a number of components in common with and operates in a similar fashion to the examples illustrated and described previously (e.g., the systemin). For the sake of brevity, these common features will not be again described in detail. Rather, previous discussion of commonly named or numbered features, unless otherwise indicated, also applies to example configurations of the system.

Similar to,shows an example of the systemin a first stage, with the pistonin a first positionand the shuttle valvein a first position. Similar to,shows an example of the systemin a second stage, with the pistonin the first positionand the shuttle valvein a second position. Similar to,shows an example of the systemwith the pistonmoving between the first positionand the second position(e.g., drawing fluid into the second piston cavitythrough the inlet port) and the shuttle valvein the second position. Similar to,shows an example of the systemwith the pistonin the second positionand the shuttle valvein the second position. Similar to,shows an example of the systemwith the pistonin the second positionand the shuttle valvein the first position. Correspondingly, as mentioned above, the pistonmay begin to move between the second positionand the first position. As a result, fluid within the second piston cavitymay be compressed, which may pressurize the fluid. In some examples, once the fluid reaches a predetermined pressure, the fluid may pass out of the second check valveand out of the outlet port.

shows another example of a process gas driven compressor system. As will be recognized, the systemshares a number of components in common with and operates in a similar fashion to the examples illustrated and described previously (e.g., the system). For the sake of brevity, these common features will not be again described below in detail. Rather, previous discussion of commonly named or numbered features, unless otherwise indicated, also applies to example configurations of the system.