LEAKAGE MONITORING FOR BOOSTER PUMP

Abstract

A pump system includes a cylinder, a piston disposed within the cylinder to define a first chamber portion and a second chamber portion within the cylinder, and a conduit system fluidly coupled to the second chamber portion. The piston is configured to move in a first direction within the cylinder to draw a working fluid into the first chamber portion, and the piston is configured to move in a second direction within the cylinder to pressurize the working fluid. The conduit system is configured to receive fluid discharged from the second chamber portion due to movement of the piston in the first direction within the cylinder, and the conduit system includes a sensor configured to determine a parameter of the fluid flowing through the conduit system, the parameter being indicative of leakage of the working fluid from the first chamber portion to the second chamber portion.

Claims

1. A pump system, comprising: a cylinder; a piston disposed within the cylinder to define a first chamber portion and a second chamber portion within the cylinder, wherein the piston is configured to move in a first direction within the cylinder to draw a working fluid into the first chamber portion, and the piston is configured to move in a second direction within the cylinder to pressurize the working fluid and discharge the working fluid from the first chamber portion; and a conduit system fluidly coupled to the second chamber portion, wherein the conduit system is configured to receive fluid discharged from the second chamber portion due to movement of the piston in the first direction within the cylinder, and the conduit system comprises a sensor configured to monitor a parameter of fluid flow through the conduit system, the parameter being indicative of leakage of the working fluid from the first chamber portion to the second chamber portion.

2. The pump system of claim 1, wherein the parameter monitored by the sensor comprises a flow rate of fluid flow through the conduit system.

3. The pump system of claim 1, wherein the parameter monitored by the sensor comprises a temperature of fluid flow through the conduit system.

4. The pump system of claim 1, comprising a control system configured to output a signal based on the parameter monitored by the sensor.

5. The pump system of claim 4, wherein the control system is configured to: compare the parameter to a threshold; and output the signal in response to determining the parameter exceeds the threshold and indicates that excessive working fluid is leaking from the first chamber portion to the second chamber portion.

6. The pump system of claim 5, wherein the control system is configured to operate in a calibration mode to establish the threshold, and the control system, in the calibration mode, is configured to: operate at a plurality of operating conditions having a first plurality of values; determine a second plurality of values of the parameter indicative of excessive leakage of the working fluid from the first chamber portion to the second chamber portion at each operating condition of the plurality of operating conditions; determine a relationship between the first plurality of values and the second plurality of values; and establish the threshold based on the relationship between the first plurality of values and the second plurality of values.

7. The pump system of claim 6, wherein the relationship associates respective first values of the parameter indicative of excessive leakage of the working fluid from the first chamber portion to the second chamber portion with corresponding second values of the plurality of operating conditions, and the control system is configured to: determine a current operating condition having one or more current values; determine a respective first value of the parameter associated with the one or more current values of the current operating condition based on the relationship; and establish the respective first value as the threshold.

8. The pump system of claim 1, comprising: an additional cylinder; and an additional piston disposed within the additional cylinder to define a third chamber portion and a fourth chamber portion within the additional cylinder, wherein the additional piston is configured to move in a third direction within the additional cylinder to draw an additional working fluid into the third chamber portion, and the additional piston is configured to move in a fourth direction within the additional cylinder to pressurize the additional working fluid and discharge the additional working fluid from the third chamber portion, wherein the conduit system is configured to receive fluid discharged from the fourth chamber portion due to movement of the additional piston in the third chamber portion.

9. The pump system of claim 8, wherein the conduit system comprises a conduit fluidly coupled to each of the second chamber portion of the cylinder and the fourth chamber portion of the additional cylinder, and the sensor is configured to monitor the parameter of fluid flow through the conduit.

10. The pump system of claim 9, comprising a first leg fluidly coupled to the second chamber portion of the cylinder, a second leg fluidly coupled to the fourth chamber portion of the additional cylinder, and a valve fluidly coupling the first leg, the second leg, and the conduit to one another to fluidly couple the conduit to each of the second chamber portion and the fourth chamber portion.

11. The pump system of claim 8, wherein the conduit system comprises a first conduit fluidly coupled to the second chamber portion of the cylinder and a second conduit fluidly coupled to the fourth chamber portion of the additional cylinder, the sensor is configured to monitor the parameter of fluid flow through the first conduit, and the conduit system comprises an additional sensor configured to monitor an additional parameter of fluid flow through the second conduit, the additional parameter being indicative of flow of the additional working fluid from the third chamber portion to the fourth chamber portion.

12. The pump system of claim 8, wherein the additional working fluid comprises the working fluid pressurized by the piston and discharged from the first chamber portion.

13. A conduit system for a pump system comprising a cylinder and a piston disposed within the cylinder to define a rod-side chamber and a piston-side chamber, opposite the rod-side chamber, wherein the conduit system comprises: a conduit that is fluidly couplable to the rod-side chamber of the pump system, wherein the piston is configured to move in a first direction within the cylinder to draw a first fluid into the piston-side chamber and discharge a second fluid from the rod-side chamber, the piston is configured to move in a second direction within the cylinder to pressurize the first fluid and discharge the first fluid from the piston-side chamber, and the conduit is configured to receive the second fluid discharged from the rod-side chamber via movement of the piston in the first direction within the cylinder; and a sensor configured to monitor a parameter of the second fluid flowing through the conduit from the rod-side chamber, wherein the parameter is indicative of flow of the first fluid from the piston-side chamber to the rod-side chamber.

14. The conduit system of claim 13, comprising a control system communicatively coupled to the sensor, wherein the control system is configured to: receive the parameter monitored by the sensor; and compare the parameter to a threshold that indicates the second fluid is comprised, at least in part, of the first fluid.

15. The conduit system of claim 14, wherein the control system is configured to output a signal in response to determining the parameter exceeds the threshold.

16. The conduit system of claim 15, wherein the control system is configured to output the signal to provide a notification.

17. A non-transitory computer-readable medium, comprising instructions that, when executed by one or more processors, are configured to cause the one or more processors to: receive a parameter from a sensor of a pump system, wherein the pump system comprises a piston disposed within a cylinder to define a first chamber portion and a second chamber portion within the cylinder, the piston is configured to move in a first direction within the cylinder to draw a working fluid into the first chamber portion, the piston is configured to move in a second direction within the cylinder to pressurize the working fluid in the first chamber portion, a conduit system of the pump system is configured to receive fluid discharged from the second chamber portion, and the parameter is associated with fluid flow through the conduit system and is indicative of working fluid flow between the first chamber portion and the second chamber portion; compare the parameter to a threshold; and output a signal based on comparison of the parameter to the threshold.

18. The non-transitory computer-readable medium of claim 17, wherein the instructions, when executed by the one or more processors, are configured to cause the one or more processors to output the signal to suspend operation of the pump system in response to determining the parameter exceeds the threshold.

19. The non-transitory computer-readable medium of claim 17, wherein the instructions, when executed by the one or more processors, are configured to cause the one or more processors to: determine a first plurality of values of a plurality of operating conditions; determine a second plurality of values of the parameter, wherein each value of the second plurality of values indicates excessive working fluid flow between the first chamber portion and the second chamber portion for a respective operating condition of the plurality of operating conditions; determine a relationship between the first plurality of values and the second plurality of values, wherein the relationship associates respective first values of the parameter indicative of excessive working fluid flow between the first chamber portion and the second chamber portion with corresponding second values of the plurality of operating conditions; and establish the threshold based on the relationship between the first plurality of values and the second plurality of values.

20. The non-transitory computer-readable medium of claim 19, wherein the instructions, when executed by the one or more processors, are configured to cause the one or more processors to: determine a current value of a current operating condition; and establish the threshold as the respective first value of the parameter associated with the current value of the current operating condition based on the relationship.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] To complete the description and provide a better understanding of the present disclosure, a set of drawings is provided. The drawings form an integral part of the description and illustrate an embodiment of the present disclosure, which should not be interpreted as restricting the scope of the disclosure, but just as an example of how the disclosure can be carried out.

[0007] FIG. 1 is a cross-sectional side view of a pump system, in accordance with an embodiment of the present disclosure.

[0008] FIG. 2 is a schematic diagram of a fluid circuit of a pump system, in accordance with an embodiment of the present disclosure.

[0009] FIG. 3 is a schematic diagram of another fluid circuit of a pump system, in accordance with an embodiment of the present disclosure.

[0010] FIG. 4 is a schematic diagram of yet another fluid circuit of a pump system, in accordance with an embodiment of the present disclosure.

[0011] FIG. 5 is a flowchart of a method for operating a fluid circuit of a pump system, in accordance with an embodiment of the present disclosure.

[0012] FIG. 6 is a flowchart of another method for operating a fluid circuit of a pump system, in accordance with an embodiment of the present disclosure.

[0013] Like numerals have been used throughout the Figures.

DETAILED DESCRIPTION

[0014] The present disclosure is directed to monitoring leakage of working fluid between chamber portions defined by a piston within a cylinder of a pump system, such as a booster. During operation of the booster, the piston moves within the cylinder to increase a pressure of the working fluid. For example, the piston is disposed within the cylinder to define a first chamber portion and a second chamber portion, the first chamber portion being configured to receive the working fluid. Movement of the piston to reduce a size of the first chamber portion pressurizes the working fluid and discharges the pressurized working fluid from the first chamber portion to another part of the pump system.

[0015] Unfortunately, the working fluid may leak between the first chamber portion and the second chamber portion. For example, there may be a gap (e.g., a gap caused by seal wear/erosion) between the piston and the cylinder through which the working fluid may flow. As a result, the working fluid may flow from the first chamber portion to the second chamber portion, thereby reducing an amount of the working fluid in the first chamber portion. Consequently, the amount of working fluid pressurized by the pump system in the first chamber portion may also decrease, and efficiency of the booster is therefore reduced.

[0016] Detecting potential leakage of the working fluid from the first chamber portion to the second chamber portion may trigger a corresponding action to address such leakage that, in turn, may improve operation of the booster. Therefore, in accordance with embodiments of the present disclosure, a conduit is fluidly coupled to the second chamber portion. Movement of the piston within the cylinder to reduce a size of the second chamber portion may cause fluid (e.g., a mixture of different fluids, such as ambient air) to discharge from the second chamber portion into the conduit. A parameter of fluid flow through the conduit from the second chamber portion is monitored to determine possible leakage of the working fluid from the first chamber portion to the second chamber portion. In some instances, the parameter is volume and/or fluid quantity. This is because leakage of the working fluid from the first chamber portion to the second chamber portion may increase a total amount of fluid in the second chamber portion, and resulting movement of the piston to reduce the size of the second chamber portion may discharge an increased amount of fluid flow into the conduit. Additionally or alternatively, the parameter may be temperature of another fluid property that can be compared to a baseline or known parameter of the fluid that is intended to be present in the second chamber and conduit system.

[0017] Regardless of the parameter, the monitored parameter may indicate that working fluid is leaking from the first chamber portion to the second chamber portion. By way of example, if the parameter is below a threshold value or within a threshold range, this may indicate that there is no excessive or undesirable leakage of the working fluid from the first chamber portion to the second chamber portion. However, if the parameter exceeds the threshold value or is beyond the threshold range, this may indicate that there is excessive or undesirable leakage of the working fluid from the first chamber portion to the second chamber portion. In response, a control system of or associated with the booster may take an action, such as notifying a user to address the leakage of the working fluid and/or suspending operation of the booster to prevent or reduce further leakage of the working fluid from the first chamber portion to the second chamber portion. Accordingly, monitoring the parameter of fluid flow through the conduit may improve operation of the booster.

[0018] FIG. 1 is a cross-sectional view of a pump system 100. The pump system 100 is a booster configured to increase pressure of a working fluid, such as a gas. The pump system 100 includes a pump portion 101 with a first cylinder 102 defining a first chamber 104 within which at least one working fluid may be pumped/pressurized. More specifically, a first piston 106 is disposed within the first chamber 104 to divide the first chamber 104 into a first chamber portion 104A and a second chamber portion 104B, with one on either side of the first piston 106. The first piston 106 is configured to move within the first chamber 104 to adjust a volume of the first chamber portion 104A and of the second chamber portion 104B. The pump portion 101 also includes a second cylinder 112 defining a second chamber 114. A second piston 116 is disposed within the second chamber 114 to divide the second chamber 114 into a third chamber portion 114A and a fourth chamber portion 114B, with one on either side of the second piston 116.

[0019] The pump portion 101 includes a first end cap 118 (e.g., a first outer cap) and a first inner cap 120 coupled to opposite ends of the first cylinder 102 to enclose the first chamber 104. The first chamber portion 104A is formed between a first end wall 122 (e.g., a first inner wall) of the first end cap 118 and a first side or surface 123 (e.g., a first pressurization side) of the first piston 106, and the second chamber portion 104B is formed between a second end wall 124 (e.g., a first outer wall) of the first inner cap 120 and a second side or surface 126 (e.g., a backside) of the first piston 106. The pump portion 101 also includes a second end cap 128 (e.g., a second outer cap) and a second inner cap 130 coupled to opposite ends of the second cylinder 112 to enclose the second chamber 114. The third chamber portion 114A is formed between a second end wall 132 (e.g., a second inner wall) of the second end cap 128 and a third side or surface 133 (e.g., a second pressurization side) of the second piston 116, and the fourth chamber portion 114B is formed between a fourth end wall 134 (e.g., a second outer wall) of the second inner cap 130 and a fourth side or surface 136 (e.g., a backside) of the second piston 116.

[0020] In some embodiments, the first chamber portion 104A and the third chamber portion 114A are configured to receive working fluid for pressurization by the first piston 106 and by the second piston 116, respectively. For example, movement of the first piston 106 away from the first end cap 118 in a first direction 138 increases a volume of the first chamber portion 104A to draw working fluid flow into the first cylinder 102 at the first chamber portion 104A. Movement of the first piston 106 in a second direction 140, opposite the first direction 138, toward the first end cap 118 reduces the volume of the first chamber portion 104A to increase the pressure of the working fluid in the first chamber portion 104A and discharge the pressurized working fluid out of the first chamber portion 104A. Movement of the second piston 116 in the second direction 140 away from the second end cap 128 increases a volume of the third chamber portion 114A to draw working fluid flow (e.g., the same or different fluid as that in the first cylinder 102) into the second cylinder 112 at the third chamber portion 114A. Movement of the second piston 116 in the first direction 138 toward the second end cap 128 reduces the volume of the third chamber portion 114A to increase the pressure of the working fluid in the third chamber portion 114A and discharge the pressurized working fluid out of the third chamber portion 114A. The first end cap 118 and the second end cap 128 include first passageways 142 and valves (e.g., one-way valves, such as check valves) to allow the working fluid to flow into and out of the first chamber portion 104A and the third chamber portion 114A, respectively.

[0021] In some embodiments, a working fluid flow directed through the pump portion 101 is pressurized by each of the first piston 106 and the second piston 116. For example, the working fluid flow is initially pressurized by the first piston 106 (e.g., a low-pressure piston) within the first chamber 104 (e.g., a low-pressure chamber), and the pressurized working fluid flow is directed from the first chamber 104 into the second chamber 114 (e.g., a high-pressure chamber) for further pressurization by the second piston 116 (e.g., a high-pressure piston). In such embodiments, the pump system 100 is a two-stage booster that pressurizes the same working fluid flow via each of the pistons 106, 116. In additional or alternative embodiments, different working fluid flows are pressurized by one of the pistons 106, 116. That is, in some instances, separate working fluid flows are directed into the first chamber 104 and into the second chamber 114 for pressurization. In such embodiments, the pump system 100 is a single-stage booster. The pump system 100 might also operate in any other stage arrangement now known or developed hereafter.

[0022] The pump portion 101 of the depicted embodiment further includes a pump drive system 146 configured to actuate the pistons 106, 116. The pump drive system 146 includes a drive shaft or rod 148 coupled to each of the first piston 106 and the second piston 116. For instance, the drive shaft 148 includes a first end 150 that extends into the second chamber portion 104B to couple to the first piston 106, as well as a second end 152 that extends into the fourth chamber portion 114B to couple to the second piston 116. As such, each of the second chamber portion 104B and the fourth chamber portion 114B is a rod-side chamber exposed to the drive shaft 148, whereas each of the first chamber portion 104A and the third chamber portion 114A is a piston-side chamber exposed to one of pistons 106, 116 and not the drive shaft 148. Movement of the drive shaft 148 drives movement of each of the pistons 106, 116, at least in the depicted embodiment. However, in other embodiments, a respective drive shaft 148 may be connected to and configured to drive the pistons 106, 116.

[0023] In the embodiment depicted in FIG. 1, movement (e.g., translation) of the drive shaft 148 in the first direction 138 drives movement of the second piston 116 toward the second end cap 128 and movement of the first piston 106 away from the first end cap 118. Accordingly, movement of the drive shaft 148 in the first direction 138 reduces a volume of the third chamber portion 114A to pressurize the working fluid in the third chamber portion 114A and increases a volume of the first chamber portion 104A to draw working fluid into the first chamber portion 104A. Movement (e.g., translation) of the drive shaft 148 in the second direction 140 drives movement of the first piston 106 toward the first end cap 118 and movement of the second piston 116 away from the second end cap 128. The drive shaft 148 may alternate between moving in the first direction 138 and in the second direction 140 to alternatively pressurize fluid in the first chamber portion 104A and in the third chamber portion 114A.

[0024] The pump drive system 146 also includes a housing 154 defining an interior 156. The drive shaft 148 extends through the interior 156, and the housing 154 shields the drive shaft 148 from an external environment, thereby protecting the drive shaft 148 from dust, debris, or other contaminants in the external environment. The housing 154 may also align the drive shaft 148 with the first chamber 104 and with the second chamber 114.

[0025] For example, in the depicted embodiment, a first adapter 158 is coupled to the housing 154 and to the first inner cap 120, and the first inner cap 120 (e.g., the second end wall 124) is coupled to the first cylinder 102 to couple and align the housing 154 to the first cylinder 102. A second adapter 160 is also coupled to the housing 154 and to the second inner cap 130, and the second inner cap 130 (e.g., the fourth end wall 134) is coupled to the second cylinder 112 to couple and align the housing 154 to the second cylinder 112. The drive shaft 148 extends through the adapters 158, 160 and into the cylinders 102, 112 aligned with the housing 154. Moreover, the first end cap 118 (e.g., the first end wall 122) is coupled to the first cylinder 102, and first stay rods 162 are coupled to the first adapter 158 and to the first end cap 118, thereby providing further securement between the housing 154 coupled to the first adapter 158 and the first cylinder 102 coupled to the first end cap 118. The second end cap 128 (e.g., the second end wall 132) is coupled to the second cylinder 112, and second stay rods 164 are coupled to the second adapter 160 and to the second end cap 128, thereby providing further securement between the housing 154 coupled to the second adapter 160 and the second cylinder 112 coupled to the second end cap 128. However, in other embodiments, the housing 154 may be coupled to one or more cylinders in any manner now known or developed hereafter.

[0026] In some circumstances, working fluid may leak from the first chamber portion 104A to the second chamber portion 104B and/or from the third chamber portion 114A to the fourth chamber portion 114B. Consequently, an amount of working fluid pressurized by the pump system 100 in the first chamber portion 104A and/or in the third chamber portion 114A may be reduced, thereby reducing efficiency of operation of the pump system 100. In accordance with embodiments of the present application, leakage of working fluid from the first chamber portion 104A to the second chamber portion 104B and/or from the third chamber portion 114A to the fourth chamber portion 114B is detected. For example, an increased amount of working fluid in the second chamber portion 104B and/or in the fourth chamber portion 114B, as caused by leakage from the first chamber portion 104A to the second chamber portion 104B and/or from the third chamber portion 114A to the fourth chamber portion 114B, may change a parameter related to fluid flow discharged from the second chamber portion 104B and/or from the fourth chamber portion 114B. Thus, the parameter may be monitored to determine the increased amount of working fluid in the second chamber portion 104B and/or in the fourth chamber portion 114B corresponding to leakage from the first chamber portion 104A to the second chamber portion 104B and/or from the third chamber portion 114A to the fourth chamber portion 114B.

[0027] FIG. 2 is a schematic diagram of a fluid circuit 200 that may be implemented in the pump system 100. The fluid circuit 200 includes a conduit system 202 fluidly coupled to the pump portion 101. Certain components of the pump system 100, such as the end caps 118, 128, the inner caps 120, 130, and the adapters 158, 160, are not shown for visualization purposes. Additionally, a working fluid source 204 (e.g., a working fluid reservoir, a working fluid processing system) is shown directing working fluid into the pump portion 101 in the illustrated embodiment, but the working fluid source 204 need not be a part of the pump system 100. In the illustrated embodiment, separate working fluid flows are directed to the respective cylinders 102.

[0028] That is, the working fluid source 204 directs a first working fluid flow 206 into the first cylinder 102, such as into the first chamber portion 104A (e.g., via the first passageway 142 of the first end cap 118), and a second working fluid flow 208 into the second cylinder 112, such as into the third chamber portion 114A (e.g., via the first passageway 142 of the second end cap 128). Therefore, the pistons 106, 116 separately pressurize the working fluid flows 206, 208. For example, movement of the drive shaft 148 in the first direction 138 causes the second piston 116 to pressurize the second working fluid flow 208 in the third chamber portion 114A, and movement of the drive shaft 148 in the second direction 140 causes the first piston 106 to pressurize the first working fluid flow 206 in the first chamber portion 104A.

[0029] After the first working fluid flow 206 and second working fluid flow 208 are pressurized by the pump portion 101, these working fluid flows 206, 208 are discharged from the cylinders 102, 112, respectively, and directed to a working fluid target 210 (e.g., another component of the pump system 100, a component external to the pump system 100). To this end, a first valve 212, which may be a one-way valve, such as a check valve, blocks the first working fluid flow 206 from exiting the first cylinder 102 toward the working fluid source 204, thereby forcing the pressurized first working fluid flow 206 to discharge toward the working fluid target 210, and a second valve 214, which may be a one-way valve, such as a check valve, blocks the second working fluid flow 208 from exiting the second cylinder 112 toward the working fluid source 204, thereby forcing the pressurized second working fluid flow 208 to discharge toward the working fluid target 210.

[0030] As an example, the pressurized working fluid flows 206, 208 discharged from the cylinders 102, 112, respectively, may be combined and directed to the same working fluid target 210. Additionally or alternatively, the pressurized working fluid flows 206, 208 may be separately directed (e.g., in parallel with one another) to the same working fluid target 210 or to different working fluid targets 210. In either example, the pump system 100 is a single-stage booster in which each working fluid flow 206, 208 undergoes a single pressurization by one of the pistons 106, 116. A valve 216, which may be a one-way valve, such as a check valve, blocks pressurized working fluid flows 206, 208 from re-entering the first cylinder 102, and a fourth valve 218, which may be a one-way valve, such as a check valve, blocks pressurized working fluid flows 206, 208 from re-entering the second cylinder 112. Thus, the pressurized working fluid flows 206, 208 are forced toward the working fluid target 210.

[0031] The conduit system 202 is fluidly coupled to the second chamber portion 104B and to the fourth chamber portion 114B and is therefore configured to receive fluid from the second chamber portion 104B and from the fourth chamber portion 114B. For example, movement of the first piston 106 in the first direction 138 (e.g., caused by movement of the drive shaft 148 in the first direction 138) reduces a size of the second chamber portion 104B and causes fluid to flow from the second chamber portion 104B into a first leg or segment 220 of the conduit system 202. Additionally, movement of the second piston 116 in the second direction 140 (e.g., caused by movement of the drive shaft 148 in the second direction 140) reduces a size of the fourth chamber portion 114B and causes fluid to flow from the fourth chamber portion 114B into a second leg or segment 222 of the conduit system 202. By way of example, the first leg 220 and the second leg 222 may be fluidly coupled to the second passageways 144 of the inner caps 120, 130.

[0032] The illustrated first leg 220 and the second leg 222 are fluidly coupled to a valve 224, such as a three-way valve, of the conduit system 202. The third valve 224 is fluidly coupled to a third leg or segment 226 of the conduit system 202 and is therefore configured to direct the fluid from each of the first leg 220 and the second leg 222 (e.g., a combined flow of fluid from the legs 220, 222) to the third leg 226. Thus, as the pistons 106, 116 move, such as in a reciprocating motion driven by the drive shaft 148, fluid flows from the second chamber portion 104B and from the fourth chamber portion 114B through the third leg 226.

[0033] In certain embodiments, the second chamber portion 104B and the fourth chamber portion 114B may at least be partially filled with an additional fluid during operation of the fluid circuit 200 in which the pistons 106, 116 move within their respective cylinders 102, 112. By way of example, movement of the first piston 106 in the second direction 140 (e.g., as caused by movement of the drive shaft 148 in the second direction 140) increases a size of the second chamber portion 104B. The increased size of the second chamber portion 104B may cause the additional fluid, such as ambient air and/or process fluid (e.g., fluid dedicated to pressurizing the second chamber portion 104B, such as to block undesirable intake of external contaminants) from a process fluid source, to be drawn into the second chamber portion 104B. Further, movement of the second piston 116 in the first direction 138 (e.g., as caused by movement of the drive shaft 148 in the first direction 138) increases a size of the fourth chamber portion 114B. The increased size of the fourth chamber portion 114B may cause additional fluid, such as ambient air and/or process fluid (e.g., the same or different process fluid as that in the second chamber portion 104B), to be drawn into the fourth chamber portion 114B. For this reason, the fluid directed from the second chamber portion 104B and/or from the fourth chamber portion 114B into the conduit system 202 may include at least a portion of the additional fluid.

[0034] Furthermore, in some circumstances, the working fluid may flow or leak from the first chamber portion 104A to the second chamber portion 104B and/or from the third chamber portion 114A to the fourth chamber portion 114B. By way of example, a gap or space may form between the first piston 106 and the first cylinder 102 and/or between the second piston 116 and the second cylinder 112 (e.g., caused by wear of the pistons 106, 116 and/or of the cylinders 102, 112). This leakage may reduce an amount of working fluid in the first chamber portion 104A and/or in the third chamber portion 114A, thereby reducing efficiency of operation to pressurize working fluid in the first chamber portion 104A and/or in the third chamber portion 114A. Additionally, this leakage may cause the working fluid to mix or combine with the additional fluid in the second chamber portion 104B and/or in the fourth chamber portion 114B. Thus, there may be an increased total amount of fluid in the second chamber portion 104B and/or in the fourth chamber portion 114B. Consequently, there is also an increased amount of fluid flow from the second chamber portion 104B and/or from the fourth chamber portion 114B into the conduit system 202 caused by movement of the pistons 106, 116 within their respective cylinders 102, 112. For example, there may be an increased amount of fluid flow through the third leg 226.

[0035] An increased amount of fluid flow from the second chamber portion 104B and/or from the fourth chamber portion 114B to the conduit system 202 may change a parameter related to fluid flow through the conduit system 202. By way of example, the increased amount of fluid flow through the third leg 226 may increase a fluid flow rate through the third leg 226. Additionally or alternatively, the increased amount of fluid flow through the third leg 226 may increase a temperature of the fluid in the third leg 226. Thus, one or more parameters may be monitored to determine an increased amount of fluid flow through the conduit system 202 (e.g., through the third leg 226), which indicates leakage of working fluid from the first chamber portion 104A to the second chamber portion 104B and/or from the third chamber portion 114A to the fourth chamber portion 114B.

[0036] For this reason, the conduit system 202 includes a sensor 228 configured to determine the parameter at the third leg 226. In some embodiments, the sensor 228 includes a flowmeter configured to determine a fluid flow rate through the third leg 226. In additional or alternative embodiments, the sensor 228 includes a temperature sensor configured to determine a temperature of fluid flowing through the third leg 226. In further embodiments, the sensor 228 may include any other suitable type of sensor configured to determine a corresponding parameter, such as pressure, a fluid composition, a flow speed, and so forth, at any suitable location of the conduit system 202.

[0037] The conduit system 202 also includes or is communicatively coupled to a control system 230 (e.g., control circuitry). The control system 230 includes a memory 232 and a processor 234 (e.g., processing circuitry). The memory 232 includes read only memory (ROM), random access memory (RAM), magnetic disk storage media devices, optical storage media devices, flash memory devices, electrical, optical, or other physical/tangible (e.g., non-transitory) memory storage devices. Thus, in general, the memory 232 includes one or more computer-readable storage media (e.g., a memory device) encoded with software with computer executable instructions that may be executed to effectuate the operations described herein. For example, the memory 232 stores or is encoded with instructions for operating the pump system 100. The processor 234 includes a collection of one or more microcontrollers and/or microprocessors, for example, each configured to execute respective software instructions stored in the memory 232. The processor 234 is configured to, for example, execute the instructions stored in the memory 232 to operate the pump system 100.

[0038] By way of example, the control system 230 may be communicatively coupled to the sensor 228 and may be configured to operate the pump system 100 based on the parameter monitored by the sensor. For instance, the pump system 100 may be configured to compare a value of the parameter to a threshold value or a threshold range indicative of leakage of working fluid from the first chamber portion 104A to the second chamber portion 104B and/or from the third chamber portion 114A to the fourth chamber portion 114B.

[0039] In response to determining that the value of the parameter exceeds the threshold value or is outside of the threshold range (either or both of which may be indicative of working fluid leakage), the control system 230 may be configured to operate to mitigate the working fluid leakage. For example, the control system 230 may be configured to output a notification to prompt a user (e.g., an operator, a technician) to perform an action to mitigate the working fluid leakage, such as to inspect and/or repair the pump portion 101. The notification may include a visual output (e.g., a light), an audio output (e.g., an alarm sound), a haptic output (e.g., a vibration), or any other suitable type of output. In some embodiments, the notification may be transmitted to a user device, such as a mobile phone or tablet. Additionally or alternatively, the control system 230 may be configured to adjust operation of the pump system 100. For example, the control system 230 may be configured to suspend operation of the pump portion 101 (e.g., to stop movement of the drive shaft 148) to avoid continued operation with working fluid leakage. In any of these operations of the control system 230, further working fluid leakage may be prevented or at least discouraged.

[0040] Additionally, in some embodiments, the control system 230 may be configured to operate in a calibration mode to establish the threshold value and/or the threshold range of the parameter. In the calibration mode, the pump system 100 operates under multiple combinations of different values for various operating conditions. The values of a specific parameter indicative of working flow leakage are determined at those combinations to determine a relationship between the value of the specific parameter and the value of other operating conditions that would indicate working fluid leakage. The threshold value and/or threshold range is then established based on the relationship (i.e., empirically).

[0041] In an example, the pump system 100 may operate under different combinations of ambient air temperatures surrounding the conduit system 202 and fluid pressures in the conduit system 202. At each of those combinations, the fluid temperature in the third leg 226 indicative of working fluid leakage is determined. In other words, at a particular combination of ambient air temperature and fluid pressure, the fluid temperature in the third leg 226 during a working fluid leakage is determined. Since changes in ambient air temperature and/or fluid pressure may cause corresponding changes in the fluid temperature in the third leg 226 (e.g., an increased ambient air temperature may naturally increase the temperature of the fluid flow in the third leg 226), the fluid temperature in the third leg 226 during a working fluid leakage (e.g., an intentionally induced working fluid leakage) is determined to confirm that the particular fluid temperature is effectuated by the working fluid leakage, rather than by the ambient air temperature and/or fluid pressure condition. Thus, the threshold value and/or the threshold range may be dynamically adjusted based on the combination of operating conditions to provide a more accurate reference point indicating potential working fluid leakage.

[0042] Put another way, the relationship between the value of the specific parameter and the values of the operating conditions may provide the threshold value and/or the threshold range at various operating conditions (e.g., having different combinations of operating condition values). As an example, at a first operating condition having a first ambient air temperature (e.g., a lower ambient air temperature) and a first fluid pressure (e.g., a lower fluid pressure), the relationship may provide that a first threshold value (e.g., a lower value) of the fluid temperature in the third leg 226 that is indicative of working fluid leakage. At a second condition having a second ambient air temperature (e.g., a higher ambient air temperature) and a second fluid pressure (e.g., a high fluid pressure), the relationship may provide a second threshold value of the fluid temperature (e.g., a higher value) of the fluid temperature in the third leg 226 that is indicative of working fluid leakage. As such, at a certain condition having a particular ambient air temperature and/or a particular fluid pressure, the relationship provides a corresponding threshold value and/or threshold range. Thus, the threshold value and/or threshold range is selected and established based on the relationship and the determined current operating conditions.

[0043] In some embodiments, the relationship may include a mathematical equation. In additional or alternative embodiments, the relationship may include a database table. In either embodiment, the relationship may be stored in the memory 232 for reference and retrieval by the processor 234 to establish the threshold value and/or the threshold range for a particular operating condition. Although fluid temperature in the third leg 226 is provided as a specific example herein, the calibration mode may be used to set the threshold value and/or the threshold range for any other suitable parameter, such as a flow rate, a fluid pressure, a flow speed, and the like, in the conduit system 202 that would indicate working fluid leakage from the first chamber portion 104A to the second chamber portion 104B and/or from the third chamber portion 114A to the fourth chamber portion 114B.

[0044] In certain embodiments, the conduit system 202 directs fluid to the first chamber portion 104A and/or to the third chamber portion 114A. For example, in circumstances in which a portion of the working fluid flows 206, 208 are contained in the second chamber portion 104B and in the fourth chamber portion 114B, respectively, the conduit system 202 may redirect the working fluid flows 206, 208 from the second chamber portion 104B and/or from the fourth chamber portion 114B to the first chamber portion 104A and/or to the third chamber portion 114A. Thus, the conduit system 202 enables such working fluid flows 206, 208 to be pressurized (e.g., even though the working fluid flows 206, 208 may have initially bypassed the pistons 106, 116) instead of being directed out away from the pump portion 101, thereby increasing operational efficiency of the fluid circuit 200. As an example, the conduit system 202 may direct the working fluid flows 206, 208 to one of the first chamber portion 104A or the third chamber portion 114A (e.g., a single conduit extends from the third leg 226 one of the first chamber portion 104A or the third chamber portion 114A). As another example, the conduit system 202 may direct the working fluid flows 206, 208 to each of the first chamber portion 104A and the third chamber portion 114A (e.g., separate conduits extend from the third leg 226 to the first chamber portion 104A and to the third chamber portion 114A, and fluid may split between the separate conduits).

[0045] In either case, a filter 236 or similar component may be used to remove fluidic particles other than the working fluid flows 206, 208 from the conduit system 202 to avoid directing other fluid (e.g., ambient air) into the first chamber portion 104A and/or into the third chamber portion 114A. Thus, the filter 236 may prevent or at least discourage undesirable mixing between the working fluid flows 206, 208 with other fluid, as well as subsequent pressurization of fluid other than the working fluid flows 206, 208. Consequently, a more desirable composition of the working fluid flows 206, 208 may be pressurized in the first chamber portion 104A and/or in the third chamber portion 114A.

[0046] The techniques discussed herein may be implemented in other embodiments of fluid circuits. For example, FIG. 3 is a schematic diagram of a fluid circuit 300 that may be implemented in the pump system 100. The fluid circuit 300 includes the conduit system 202 fluidly coupled to a pump portion, similar to FIG. 2. Consequently, the conduit system 202 is configured to receive fluid from the second chamber portion 104B and from the fourth chamber portion 114B. For example, the conduit system 202 may include the first leg 220 fluidly coupled to the second chamber portion 104B, the second leg 222 fluidly coupled to the fourth chamber portion 114B, and the third leg 226 fluidly coupled to the first leg 220 and to the second leg 222 via the valve 224. Thus, the third leg 226 is configured to receive fluid from each of the second chamber portion 104B and the fourth chamber portion 114B. The sensor 228 is configured to monitor a parameter of the fluid flow through the third leg 226, and the control system 230 is configured to utilize the parameter to determine whether there is working fluid leakage from the first chamber portion 104A to the second chamber portion 104B and/or from the third chamber portion 114A to the fourth chamber portion 114B (e.g., based on a comparison between the parameter and a threshold). However, now the pump system 100 is a two-stage booster that pressurizes a working fluid flow 304 via the first piston 106 and then via the second piston 116.

[0047] Accordingly, in the illustrated embodiment, the working fluid flow 304 directed by the working fluid source 204 is pressurized by each of the first piston 106 and the second piston 116. That is, the working fluid source 204 directs the working fluid flow 304 into the first cylinder 102, such as into the first chamber portion 104A (e.g., via the first passageway 142 of the first end cap 118), where the first piston 106 pressurizes the working fluid flow 304 and discharges the working fluid flow 304 (e.g., via movement of the drive shaft 148 in the second direction 140) as a first pressurized working fluid flow 306. The first pressurized working fluid flow 306 is then directed into the third chamber portion 114A (e.g., via the first passageway 142 of the second end cap 128) and is further pressurized by the second piston 116 (e.g., via movement of the drive shaft 148 in the first direction 138) to provide a second pressurized working fluid flow 308. The second pressurized working fluid flow 308 is discharged from the second cylinder 112 and directed toward the working fluid target 210.

[0048] To effectuate this scheme, the pump portion 101 includes cylinder valves arranged differently as compared to that in the pump portion 101 of FIG. 2. For instance, a first valve 310, which may be a one-way valve, such as a check valve, may block the working fluid flow 304 (e.g., the first pressurized working fluid flow 306) from exiting the first cylinder 102 toward the working fluid source 204, and a second valve 312, which may be a one-way valve, such as a check valve, may block the first pressurized working fluid flow 306 from re-entering the first cylinder 102. Thus, the first pressurized working fluid flow 306 is forced toward the second cylinder 112. Moreover, a third valve 314, which may be a one-way valve, such as a check valve, may block the working fluid flow 304 (e.g., the second pressurized working fluid flow 308) from exiting the second cylinder 112 toward the first cylinder 102, and a fourth valve 316, which may be a one-way valve, such as a check valve, may block the second pressurized working fluid flow 308 from re-entering the second cylinder 112. As such, the second pressurized working fluid flow 308 is forced toward the working fluid target 210. Therefore, the valves 310, 312, 314, 316 may facilitate operation of the pump system 100 as a two-stage booster to pressurize the working fluid flow 304 via both pistons 106, 116.

[0049] As another example variation, FIG. 4 is a schematic diagram of a fluid circuit 400 that may be implemented in the pump system 100. In the illustrated embodiment, the pump system 100 is a single-stage booster in which respective working fluid flows 206, 208 are separately pressurized by the pistons 106, 116. That is, the first piston 106 pressurizes the first working fluid flow 206 (e.g., via movement of the drive shaft 148 in the second direction 140), the second piston 116 pressurizes the second working fluid flow 208 (e.g., via movement of the drive shaft 148 in the first direction 138), and the pressurized working fluid flows 206, 208 are directed to the working fluid target 210 (e.g., as a combined working fluid flow). However, this is merely an example and concepts illustrated in FIG. 4 might also be applicable to pumps with two or more stages (e.g., as shown in FIG. 3).

[0050] The fluid circuit 400 includes a conduit system 402 configured to receive fluid from the second chamber portion 104B and from the fourth chamber portion 114B. The illustrated conduit system 402 includes a first conduit 404 fluidly coupled to the second chamber portion 104B and a second conduit 406 fluidly coupled to the fourth chamber portion 114B. For example, the first conduit 404 may be fluidly coupled to the second passageways 144 of the first adapter 158, and the second conduit 406 may be fluidly coupled to the second passageways 144 of the second adapter 160. Additionally, the first conduit 404 and the second conduit 406 are fluidly separate from one another and therefore direct different fluid flows therethrough.

[0051] That is, the first conduit 404 is configured to receive a first fluid flow 408 from the second chamber portion 104B, and the second conduit 406 is configured to receive a second fluid flow 410 from the fourth chamber portion 114B. By way of example, the first fluid flow 408 may contain a portion of the first working fluid flow 206 directed into the first chamber portion 104A and leaked from the first chamber portion 104A into the second chamber portion 104B, and/or the second fluid flow 410 may contain a portion of the second working fluid flow 208 directed into the third chamber portion 114A and leaked from the third chamber portion 114A into the fourth chamber portion 114B. As such, the conduits 404, 406 may receive separate leaked flows of the working fluid flows 206, 208.

[0052] Additionally, a first sensor 228A is configured to determine a parameter of the first conduit 404, and a second sensor 228B (e.g., the same or a different type than the first sensor 228A) is configured to determine a parameter of the second conduit 406. Accordingly, each sensor 228 is dedicated to monitor a parameter indicative of leakage within one of the cylinders 102, 112. The control system 230 is communicatively coupled to each of the sensors 228 and is configured to utilize the respective parameters monitored by the sensors 228 to determine whether there is a potential leakage in the cylinders 102, 112. That is, the control system 230 is configured to determine whether there is a leakage in the first cylinder 102 from the first chamber portion 104A to the second chamber portion 104B based on the parameter monitored by the first sensor 228A (e.g., by comparing the parameter to a threshold), and the control system 230 is configured to determine whether here is a leakage in the second cylinder 112 from the third chamber portion 114A to the fourth chamber portion 114B based on the parameter monitored by the second sensor 228B (e.g., by comparing the parameter to a threshold that is the same or different than that used with respect to the parameter monitored by the first sensor 228A).

[0053] In the illustrated embodiment, the conduit system 402 is configured to direct fluid from each of the first conduit 404 and the second conduit 406 to the first chamber portion 104A and/or to the third chamber portion 104B to enable the working fluid flows 206, 208 directed into the second chamber portion 104B and/or into the fourth chamber portion 114B to be pressurized. As an example, fluid from the first conduit 404 may be directed to one of the first chamber portion 104A or the third chamber portion 104B, and fluid from the second conduit 406 may be directed to the other of the first chamber portion 104A or the third chamber portion 104B. That is, the first conduit 404 and the second conduit 406 may separately direct fluid to the first chamber portion 104A and to the third chamber portion 104B. As another example, fluid from the first conduit 404 may combine with fluid from the second conduit 406 before being directed to the first chamber portion 104A and/or to the third chamber portion 104B. In either case, one or more filters (e.g., a separate filter dedicated for each conduit 404, 406) may be implemented to block fluid other than the working fluid flows 206, 208 from being directed by the conduit system 202 to the first chamber portion 104A and/or to the third chamber portion 104B.

[0054] Although the discussed embodiments of the pump system 100 include two cylinders 102, 112 that are configured to pressurize working fluid, the pump system 100 may include any suitable quantity of cylinders in additional or alternative embodiments. In such embodiments, each cylinder includes a piston disposed therein to divide the chamber of the cylinders, and the pistons are configured to move within their corresponding cylinders to pressurize working fluid in a chamber portion of each cylinder. Meanwhile, a conduit system is fluidly coupled to each cylinder, and the control system 230 is configured to receive a parameter indicative of fluid flow through the conduit system to determine working fluid leakage within the cylinders.

[0055] Furthermore, although movement of the pistons 106, 116 in opposite directions 138, 140 (e.g., as driven by the drive shaft 148) pressurizes working fluid in the illustrated embodiments, in additional or alternative embodiments, the pistons 106, 116 may move in separate directions, and a conduit system is configured to receive fluid from the cylinders 102, 112 during such movement of the pistons 106, 116. By way of example, the first piston 106 may move in a first direction to increase the volume of the first chamber portion 104A and reduce the volume of the second chamber portion 104B. Meanwhile, the second piston 116 may move in a second direction, transverse (e.g., perpendicular) to the first direction, to increase the volume of the third chamber portion 114A and reduce the volume of the fourth chamber portion 114B. Such movement of the first piston 106 and of the second piston 116 to reduce the volume of both the second chamber portion 104B and the fourth chamber portion 114B, respectively, may direct fluid from both the second chamber portion 104B and the fourth chamber portion 114B to the conduit system. Thus, regardless of the orientation of the direction of movement of the pistons 106, 116 relative to one another, the arrangement of the pistons 106, 116 to adjust the volume of the second chamber portion 104B and the volume of the fourth chamber portion 114B may cause fluid to flow into the conduit system for monitoring leakage of working fluid.

[0056] Each of FIGS. 5 and 6 discussed below illustrates a respective method for operating a pump system, such as the pump system 100. In some embodiments, the operations of each method may be performed by a single entity, such as by the control system 230. Additionally or alternatively, different operations of the methods may be performed by different entities. It should be noted that each method may be performed differently than depicted. For example, an additional operation may be performed, a depicted operation may be performed differently, a depicted operation may not be performed, and/or any of the depicted operations may be performed in a different order. Further, the respective operations of the methods may be performed in any suitable manner with respect to one another, such as sequentially or concurrently (e.g., in parallel).

[0057] FIG. 5 is a flowchart of a method 450 for operating the pump system. At block 452, a parameter indicative of working fluid flow or leakage between chamber portions of a cylinder of the pump system is determined. For example, a piston may be disposed within the cylinder to define a first chamber portion and a second chamber portion. The first chamber portion is configured to receive a working fluid flow, and the piston is configured to move within the cylinder to reduce a size of the first chamber portion (e.g., increase a size of the second chamber portion) to pressurize the working fluid flow in the first chamber portion. The conduit system (e.g., a leg, a segment, a conduit) is fluidly coupled to the second chamber portion. Thus, movement of the piston within the cylinder to reduce a size of the second chamber portion (e.g., increase a size of the first chamber portion) directs fluid out of the second chamber portion and through the conduit system. Leakage of working fluid from the first chamber portion to the second chamber portion may cause some of the working fluid to flow through the conduit system. Accordingly, the fluid flow through the conduit system may include the working fluid. The parameter indicative of working fluid flow between chamber portions of the cylinder is associated with the fluid flow through the conduit system. For instance, the parameter may include a flow rate, a temperature, a pressure, a composition, and so forth of the fluid flow.

[0058] At block 454, the parameter is compared to a threshold, such as a threshold value (e.g., for flow rate monitoring, a value between 500-1000 cubic centimeters per minute of flow rate) or a threshold range. The threshold is associated with a value of the parameter that indicates excessive or undesirable working fluid flow between the chamber portions of the cylinder. By way of example, working fluid flow from the first chamber portion to the second chamber portion increases an amount of fluid in the second chamber portion and therefore increases an amount of fluid flow through the conduit system during movement of the piston to reduce a size of the second chamber portion. The increased amount of fluid flow through the conduit system may change the value of the parameter (e.g., beyond typical or expected values while working fluid does not leak into the second chamber portion). Thus, a sufficient change in the value of the parameter, as indicated by the comparison of the parameter to the threshold and caused by working fluid flow from the second chamber portion to the conduit system, indicates undesirable or excessive leakage of working fluid from the first chamber portion to the second chamber portion.

[0059] At block 456, a signal is output based on comparison of the parameter to the threshold. For example, the signal may be output in response to a value of the parameter exceeding the threshold value, a value of the parameter dropping below the threshold value, a value of the parameter being outside of the threshold range, or any other suitable relationship of the value of the parameter with respect to the threshold to indicate excessive working fluid flow between the chamber portions of the cylinder. The signal may be output to provide a notification to a user to perform an operation with respect to the pump system to address the excessive working fluid flow between the chamber portions, such as to change, repair, or implement a seal of the piston to block working fluid flow between the chamber portions. Additionally or alternatively, the signal may be output to suspend operation of the pump system, such as to block movement of the piston and/or to block flow of working fluid into the cylinder to avoid additional leakage of working fluid within the cylinder. In further embodiments, the signal may be output to cause the conduit system to direct fluid to the first chamber portion. Thus, working fluid that initially bypassed the piston may still be pressurized. In such embodiments, the fluid in the conduit system is filtered to remove fluid other than working fluid, thereby blocking other fluid from mixing with the working fluid in the first chamber portion to maintain a desirable composition of the working fluid being pressurized in the first chamber portion.

[0060] In certain embodiments, operations of the method 450 may be performed separately from operations to pressurize the working fluid and direct the pressurized working fluid to a target. That is, the method 450 may be dedicated to determining whether there is excessive working fluid flow between the chamber portions of the cylinder instead of, for example, for purposes of delivering a certain amount of pressurized working fluid to the target (e.g., to direct a threshold flow rate of working fluid exceeding a threshold pressure to the target). Similarly, while the pump system operates to pressurize working fluid and direct the pressurized working fluid to the target, the method 450 may not be in operation. By way of example, during operation of the method 450, the pump system may pressurize the working fluid to a relatively lower pressure as compared to that during operation to deliver desirably pressurized working fluid to the target. In such embodiments, the method 450 may be operated at a particular frequency, such as at specified time intervals, after a quantity of cycles of operations dedicated to pressurizing working fluid, and the like. In additional or alternative embodiments, operations of the method 450 may be performed concurrently with operations to pressurize working fluid and direct the pressurized working fluid to the target. That is, while the pump system operates to pressurize working fluid and direct the pressurized working fluid to the target, the method 450 is also being performed to determine leakage of working fluid.

[0061] Additionally, in some embodiments, the method 450 may be operated for a particular duration of time to verify accuracy of the obtained parameter. For example, multiple values of the parameter may be determined during the duration of time, and an average (e.g., a mathematical mean, a mathematical median) of the values may be calculated and compared to the threshold. As such, the comparison to the threshold may more accurately indicate whether there is excessive working fluid flow between chamber portions of the cylinder (e.g., instead of a brief, irregular flow of fluid through the conduit system, such as caused by abnormal movement of the piston rather than working fluid leakage).

[0062] It should also be noted that the method 450 may be performed for multiple cylinders. As an example, a single parameter may indicate working fluid flow between chamber portions within any one of a plurality of cylinders. For instance, a single conduit may be fluidly coupled to multiple chamber portions, and a parameter of fluid flow through the conduit may be determined. The comparison between the parameter and the threshold may therefore be used to determine whether there is working fluid leakage within at least one of the cylinders. As another example, the method 450 may be separately performed for different cylinders. That is, a different parameter indicative of working fluid flow between chamber portions may be determined for different cylinders. In other words, each parameter indicates working fluid flow between chamber portions of one of the cylinders and not of another of the cylinders. To this end, respective conduits are fluidly coupled to the cylinders, and the parameter of different fluid flows through the respective conduits are determined. Thus, working fluid leakage within each individual cylinder may be monitored based on the parameters. In such embodiments, the parameters for different cylinders may be the same type or a different type, and/or the parameters for different cylinders may be compared to the same threshold or to a different threshold.

[0063] FIG. 6 is a flowchart of a method 500 for operating the pump system in a calibration mode to determine a threshold (e.g., the threshold of FIG. 5 used to determine excessive working fluid flow between chamber portions of a cylinder) at different operating conditions. The pump system includes a pump portion with a cylinder and a piston disposed in the cylinder to define a first chamber portion configured and a second chamber portion. The piston is configured to move within the cylinder to pressurize working fluid in the first chamber portion. The pump system also includes a conduit system fluidly coupled to the second chamber portion and configured to receive fluid flow from the second chamber portion as a result of movement of the piston within the cylinder to reduce a size of the second chamber portion.

[0064] At block 502, the pump system is operated in the calibration mode at different operating conditions having a first plurality of values. By way of example, the operating conditions include ambient air temperature and pressure of fluid directed through the conduit system, and the first plurality of values includes different combinations of the ambient air temperature and the pressure of fluid.

[0065] At block 504, a second plurality of values of a parameter indicative of excessive or undesirable working fluid flow between the chamber portions of the cylinder is determined at each operating condition. That is, for each combination of the first plurality of values of the operating conditions, a corresponding value of the parameter indicative of excessive working fluid flow between the chamber portions is determined. For example, at each combination of the ambient air temperature and the pressure of fluid, the particular temperature of fluid that would indicate excessive working fluid flow between the chamber portions may be determined. Indeed, because a change in the ambient air temperature and/or in the pressure of fluid may change the expected temperature of fluid flow through the conduit system when there is no excessive working fluid flow between the chamber portions, the temperature that does indicate excessive working fluid flow between the chamber portions may also correspondingly change.

[0066] For instance, at a first operating condition associated with a relatively lower ambient air temperature and a relatively lower pressure of fluid, a relatively lower temperature of fluid may indicate excessive working fluid flow between the chamber portions. However, at a second operating condition associated with a relatively higher ambient air temperature and a relatively higher pressure of fluid, a relatively higher temperature of fluid may indicate excessive working fluid flow between the chamber portions (e.g., the relatively lower temperature of fluid associated with the first operating condition may no longer indicate excessive working fluid flow between the chamber portions at the relatively higher ambient air temperature and the relatively higher pressure of fluid in the second condition). Thus, the second plurality of values of the parameter provides different indications of excessive working fluid flow between the chamber portions at the different operating conditions having the first plurality of values.

[0067] At block 506, a relationship between the first plurality of values and the second plurality of values is determined. The relationship may include a mathematical equation and/or a database table. In either case, the relationship associates a respective second value of the parameter (e.g., a temperature value of fluid) corresponding to various first values of the operating conditions (e.g., an ambient temperature value, a pressure value of fluid), each respective second value being indicative of excessive working fluid flow between the chamber portions at a particular operating condition.

[0068] At block 508, the threshold is established based on the relationship. That is, current first values of the operating condition are determined (e.g., via one or more sensors). The relationship then provides the particular second value of the parameter corresponding to the current first values of the operating condition. The particular second value is selected as the threshold indicating excessive working fluid flow between the chamber portions at the current operating condition having the current first values. By dynamically adjusting the threshold based on the first values of the operating condition (e.g., by increasing the threshold temperature value of fluid as ambient air temperature increases), the threshold may more closely reflect and correspond to the current operating condition. Stated differently, a static or fixed threshold may not accurately indicate excessive working fluid flow between the chamber portions at certain operating conditions (e.g., the temperature of fluid exceeding a lower, fixed threshold value may be caused by a high ambient air temperature rather than excessive working fluid flow between the chamber portions). Thus, a dynamically adjusted threshold may enable excessive working fluid flow between the chamber portions to be more accurately determined based on comparison with the dynamically adjusted threshold.

[0069] As used herein, unless expressly stated to the contrary, use of the phrase at least one of, one or more of, and/or, variations thereof, or the like are open-ended expressions that are both conjunctive and disjunctive in operation for any and all possible combination of the associated listed items. For example, each of the expressions at least one of X, Y and Z, at least one of X, Y or Z, one or more of X, Y and Z, one or more of X, Y or Z and X, Y and/or Z can mean any of the following: 1) X, but not Y and not Z; 2) Y, but not X and not Z; 3) Z, but not X and not Y; 4) X and Y, but not Z; 5) X and Z, but not Y; 6) Y and Z, but not X; or 7) X, Y, and Z.

[0070] Additionally, unless expressly stated to the contrary, the terms first, second, third, etc., are intended to distinguish the particular nouns they modify (e.g., element, condition, node, module, activity, operation, etc.). Unless expressly stated to the contrary, the use of these terms is not intended to indicate any type of order, rank, importance, temporal sequence, or hierarchy of the modified noun. For example, first X and second X are intended to designate two X elements that are not necessarily limited by any order, rank, importance, temporal sequence, or hierarchy of the two elements. Further as referred to herein, at least one of and one or more of can be represented using the (s) nomenclature (e.g., one or more element(s)).

[0071] Each example embodiment disclosed herein has been included to present one or more different features. However, all disclosed example embodiments are designed to work together as part of a single larger system or method. This disclosure explicitly envisions compound embodiments that combine multiple previously-discussed features in different example embodiments into a single system or method.

[0072] One or more advantages described herein are not meant to suggest that any one of the embodiments described herein necessarily provides all of the described advantages or that all the embodiments of the present disclosure necessarily provide any one of the described advantages. Numerous other changes, substitutions, variations, alterations, and/or modifications may be ascertained to one skilled in the art and it is intended that the present disclosure encompass all such changes, substitutions, variations, alterations, and/or modifications as falling within the scope of the appended claims.