CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of U.S. Provisional Application No. 62/954,214, filed December 27, 2019, titled “FLUID END HEALTH MONITORING USING DELTA PRESSURE,” and to U.S. Patent Application No. 17/134,880, filed December 28, 2020, titled “SYSTEMS AND METHODS FOR FLUID END HEALTH MONITORING,” the full disclosures of which are incorporated herein by reference for all purposes.

Field of Invention

[0002] This invention relates in general to hydraulic fracturing technology, and more particularly to monitoring the health of fluid ends.

Background

[0003] With advancements in technology over the past few decades, the ability to reach unconventional sources of hydrocarbons has tremendously increased. Hydraulic fracturing technology has led to hydrocarbon production from previously unreachable shale formations. Hydraulic fracturing operations in oil and gas production involve the pumping of hydraulic fracturing fluids at high pressures and rates into a wellbore. The high pressure cracks the formation, allowing the fluid to enter the formation. Proppants, such as silica, are included in the fluid to wedge into the formation cracks to help maintain paths for oil and gas to escape the formation to be drawn to the surface. Hydraulic fracturing fluid can also typically contain acidic chemicals. [0004] Due to the nature of hydraulic fracturing fluid, hydraulic fracturing pump fluid ends are subjected to harsh operating conditions. They pump abrasive slurries and acidic chemicals at high pressures and rates. Their lifespan is typically relatively short compared to other types of pumps. Maximizing fluid end lifespan is beneficial to the financial success of pressure pumping companies due at least in part to the high cost of fluid end replacement. Reducing the likelihood of fluid end failures also reduces maintenance costs and downtime.

Summary of the Invention

[0005] In accordance with one or more embodiments, a method of hydraulic fracturing includes providing a fracturing fluid to a pump. The pump includes a pressure sensor for measuring pressure at a fluid end. The method further include injecting the fracturing fluid from the pump into a wellhead via the fluid end, obtaining a first pressure measurement at a discharge side of the fluid end via the pressure sensor, obtaining a second pressure measurement at the discharge side of the fluid end via the pressure sensor, determining a pressure differential between the first pressure measurement and the second pressure measurement, and determining an operational condition of the fluid end based at least in part on the pressure differential and a known or estimated correlation between the pressure differential and the operational condition. In some embodiments, the first pressure measurement and second pressure measurement are derived from a pressure sample taken by the pressure sensor over a period of time. In some embodiments, the first pressure measurement is the maximum value in the pressure sample and the second measurement is the minimum value in the pressure sample. In some embodiments, the first pressure measurement and the second measurement represent a pressure fluctuation in the pressure sample. In some embodiments, the operational condition includes an estimation of remaining life of the fluid end. In some embodiments, the estimation of remaining life is negatively correlated with the pressure differential. In some embodiments, the operational condition is determined based on one or more control system data in addition to the pressure differential.

[0006] In accordance with another embodiment, a method of monitoring a fluid end of a hydraulic fracturing pump includes obtaining a first pressure measurement at a discharge side of the fluid end via a pressure sensor, obtaining a second pressure measurement at the discharge side of the fluid end via the pressure sensor, determining a pressure differential between the first pressure measurement and the second pressure measurement, and determining an operational condition of the fluid end based at least in part on the pressure differential and a known or estimated correlation between the pressure differential and the operational condition. In some embodiments, the first pressure measurement and second pressure measurement are derived from a pressure sample taken by the pressure sensor over a period of time. In some embodiments, the first pressure measurement is the maximum value in the pressure sample and the second measurement is the minimum value in the pressure sample. In some embodiments, the first pressure measurement and the second measurement represent a pressure fluctuation in the pressure sample. In some embodiments, the operational condition includes an estimation of remaining life of the fluid end. In some embodiments, the pressure differential is negatively correlated with the estimation of remaining life. In some embodiments, the operational condition is determined based on one or more control system data in addition to the pressure differential.

[0007] In yet another example embodiment, a hydraulic fracturing system includes a pump comprising a fluid end, a pressure sensor positioned to measure pressure at a discharge side of the fluid end, and a control system. The control system is configured to: obtain a first pressure measurement at the discharge side of the fluid end via the pressure sensor, obtain a second pressure measurement at the discharge side of the fluid end via the pressure sensor, determine a pressure differential between the first pressure measurement and the second pressure measurement, and determine an operational condition of the fluid end based at least in part on the pressure differential and a known or estimated correlation between the pressure differential and the operational condition. In some embodiments, the pressure sensor is a high speed, high pressure transducer. In some embodiments, the first pressure measurement and second pressure measurement are derived from a pressure sample taken by the pressure sensor over a period of time. In some embodiments, the first pressure measurement is the maximum value in the pressure sample and the second measurement is the minimum value in the pressure sample. In some embodiments, the first pressure measurement and the second measurement represent a pressure fluctuation in the pressure sample. In some embodiments, the operational condition includes an estimation of remaining life of the fluid end.

Brief Description of the Drawings

[0008] FIG. 1 is a schematic representation of an embodiment of a hydraulic fracturing system positioned at a well site.

[0009] FIG. 2 is a simplified diagrammatical representation of a hydraulic fracturing pump, in accordance with example embodiments.

[0010] FIG. 3 is a chart illustrating data points of pump rate and pressure differential.

[0011] FIG. 4 is a chart illustrating data points of delta pressure and damage accumulation rate. [0012] FIG. 5 is a flowchart illustrating a method of hydraulic fracturing, in accordance with example embodiments.

[0013] FIG. 6 includes a diagram illustrating a communications network of the automated fracturing system, in accordance with various embodiments.

Detailed Description of the Invention

[0001] The foregoing aspects, features, and advantages of the present disclosure will be further appreciated when considered with reference to the following description of embodiments and accompanying drawings. In describing the embodiments of the disclosure illustrated in the appended drawings, specific terminology will be used for the sake of clarity. However, the disclosure is not intended to be limited to the specific terms used, and it is to be understood that each specific term includes equivalents that operate in a similar manner to accomplish a similar purpose.

[0002] When introducing elements of various embodiments of the present disclosure, the articles "a", "an", "the", and "said" are intended to mean that there are one or more of the elements. The terms "comprising", "including", and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements. Any examples of operating parameters and/or environmental conditions are not exclusive of other parameters/conditions of the disclosed embodiments. Additionally, it should be understood that references to "one embodiment", "an embodiment", “certain embodiments”, or “other embodiments” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Furthermore, reference to terms such as “above”, “below”, “upper”, “lower”, “side”, “front”, “back”, or other terms regarding orientation or direction are made with reference to the illustrated embodiments and are not intended to be limiting or exclude other orientations or directions. Additionally, recitations of steps of a method should be understood as being capable of being performed in any order unless specifically stated otherwise. Furthermore, the steps may be performed in series or in parallel unless specifically stated otherwise.

[0003] FIG. 1 is a schematic representation of an embodiment of a hydraulic fracturing system 10 positioned at a well site 12. In the illustrated embodiment, pump trucks 14, which make up a pumping system 16, are used to pressurize a fracturing fluid solution for injection into a wellhead 18. A hydration unit 20 receives fluid from a fluid source 22 via a line, such as a tubular, and also receives additives from an additive source 24. In an embodiment, the fluid is water and the additives are mixed together and transferred to a blender unit 26 where proppant from a proppant source 28 may be added to form the fracturing fluid solution (e.g., fracturing fluid) which is transferred to the pumping system 16. The pump trucks 14 may receive the fracturing fluid solution at a first pressure (e.g., 80 psi to 100 psi) and boost the pressure to around 15,000 psi for injection into the wellhead 18. In certain embodiments, the pump trucks 14 are powered by electric motors.

[0004] After being discharged from the pump system 16, a distribution system 30, such as a missile, receives the fracturing fluid solution for injection into the wellhead 18. The distribution system 30 consolidates the fracturing fluid solution from each of the pump trucks 14 (for example, via common manifold for distribution of fluid to the pumps) and includes discharge piping 32 (which may be a series of discharge lines or a single discharge line) coupled to the wellhead 18. In this manner, pressurized solution for hydraulic fracturing may be injected into the wellhead 18. In the illustrated embodiment, one or more sensors 34, 36 are arranged throughout the hydraulic fracturing system 10. In embodiments, the sensors 34 transmit flow data to a data van 38 for collection and analysis, among other things.

[0005] In some embodiments, the hydraulic fracturing system 10 includes hydraulic fracturing pumps that inject fracturing fluid into the wellhead. FIG. 2 is a simplified diagrammatical representation of a hydraulic fracturing pump 50, in accordance with example embodiments. The pump 50 typically includes a power end 52 which includes a displacement mechanism 54 that is moved to pump the fluid. The pump also includes a fluid end 56 through which the fluid moves. The fluid end 56 includes a suction side 58 where fluid is drawn in and a discharge side 60 where fluid is discharged from the pump 50. One or more pressure sensors 64 are positioned to measure pressure at the discharge side 60 of the fluid end 56. The one or more pressure sensors 64 may be a high speed, high pressure transducer. In some other embodiments, one or more pressure sensors 64 may be placed on the suction side 58, or at a chamber where a plunger would pressurize the fluid, or in a different area of the fluid end.

[0006] The fracturing system 10 also includes a control system. The control system is configured to obtain a first pressure measurement at the discharge side 60 of the fluid end 56 via the pressure sensor 64, obtain a second pressure measurement at the discharge side 60 of the fluid end 56 via the pressure sensor 64, determine a pressure differential between the first pressure measurement and the second pressure measurement, and determine an operational condition of the fluid end 56 based at least in part on the pressure differential and a known or estimated correlation between the pressure differential and the operational condition. In some embodiments, the first pressure measurement and second pressure measurement are derived from a pressure sample taken by the pressure sensor 64 over a period of time. In some embodiments, the first pressure measurement is the maximum value in the pressure sample and the second measurement is the minimum value in the pressure sample. In some embodiments, the first pressure measurement and the second measurement represent a pressure fluctuation in the pressure sample. In some embodiments, the operational condition includes an estimation of remaining life of the fluid end 56.

[0007] Hydraulic fracturing operations in oil and gas production require the pumping of hydraulic fracturing fluids at high pressures and rates into a wellbore. The high pressure cracks the formation, allowing the fluid to enter the formation. Proppants, such as silica, are included in the fluid to wedge into the formation cracks to help maintain paths for oil and gas to escape the formation to be drawn to the surface. Hydraulic fracturing fluid can also typically contain acidic chemicals.

[0008] Due to the nature of hydraulic fracturing fluid, hydraulic fracturing pump fluid ends are subjected to harsh operating conditions. Fluid ends pump abrasive slurries and acidic chemicals at high pressures and rates. The lifespan of a fluid end is typically relatively short compared to other types of pumps. Maximizing fluid end lifespan is beneficial to the financial success of pressure pumping companies due at least in part to the high cost of fluid end replacement. Fluid end failures modes or conditions may include, but are not limited to broken stayrod, cavitation, cracked fluid end, D-ring failure, iron bracket and pump iron issues, keeper or spring failure, loose packing nut, loose pony rod clamp, missing pony rod clamp, packing drip, packing failure, packing grease issues, pony rod clamp and packing nut impacting, sanded-off suction manifold, valve or seat cut, valve and seat wear, among others. Reducing the likelihood of fluid end failures also reduces maintenance costs and downtime, which is important to customers. Thus, being able to estimate remaining life of a fluid end can help avoid such failures. [0009] The technology described herein utilizes using high speed, high pressure transducer(s) to determine the current running condition of the fluid end 56. This can be used to estimate or predict fluid end life expectancy. In some embodiments, by taking one individual pressure sample, the differential pressure is obtained by comparing the maximum and minimum values from that one data sample. This difference is known as delta pressure. As this variable grows larger and larger, the current operating health gets worse and the life of the asset is diminished. Thus, this can serve as a new process for monitoring fluid end health and life expectancy. It can be used in conjunction with control system data such as speeds, rates, pressures and well as with our vibration sensors that currently monitor fluid ends. Using the data from the pressure transducer to produce the delta pressure (i.e., pressure variance, pressure differential) is a critical and new metric for monitoring equipment health. Trending this data and correlating it to other variables results in new and yet to be determined equipment gains such as in efficiency, life, or redesign.

[0010] Delta pressure is a reading taken on the discharge side of the fluid end or downstream in the flow iron. This reading is associated with the pump rate (BPM). FIG. 3 is a chart 104 illustrating data points of pump rate 108 and pressure differential 106, otherwise referred to as delta pressure or pressure fluctuation. It can be observed from FIG. 3 that as pump rate 108 increases, generally so does the value of pressure differential 106. FIG. 4 is a chart 112 illustrating data points of delta pressure 116 and damage accumulation rate 114. In some embodiments, the damage accumulation rate 114 is captured using a vibration monitoring system. As shown, as delta pressure 116 increases, generally so does the associated damage accumulation rate 114. Thus, greater insight on equipment operating conditions and equipment health can be obtained by capturing delta pressure 116. [0011] Using delta pressure may serve as a more accurate means of determining operating condition and equipment health, and encompasses a greater range of variables in determining operating condition and equipment health. It can serve as the main driver and leading indicator covering the various variables such as rate, pressure, cavitation, and other operating conditions that contribute to fluid end life. In some embodiments, existing transducer hardware may be used rather than adding on new hardware.

[0012] Certain embodiments of the present technology are directed to hydraulic fracturing pump fluid ends, but alternate embodiments contemplate use of the technology in other applications, including pump power ends (e.g., crosshead bearings, pinion bearings, gear wear), engines and transmissions, electric motors, power generation equipment, pump iron, and high pressure manifold systems such as single bore iron runs to wellheads.

[0013] In addition, data analysis and prediction can utilize a machine learning model. Training can be achieved by collecting all training and testing data into a database in the cloud. A headless Internet of Things (IoT) gateway can be onsite running custom software. This software captures data from various systems (e.g., control systems, GPS sensors, flowmeters, turbines, engines, transmissions, etc.) and forwards the data to an IoT hub in the cloud. Data about equipment lifespan, make/model, and maintenance history can be imported from an enterprise maintenance application via an application programming interface (API). Third-party data can also be imported via an API.

[0014] Cloud-based machine learning services can then use a subset of that data to train and test various models to determine the correlation between the various inputs and equipment lifespan. The resulting algorithm can then be deployed in the cloud or in the field, fed the necessary parameters in real time, and the results are displayed to users and continuously updated.

[0015] The present technology presents many advantages over known systems. For example, the system is able to determine the factors contributing to early equipment failure more accurately than current methods due to more comprehensive data collection. Other systems only rely on a small subset of contributing factors. The present technology is also capable of deploying the resulting prediction algorithm onsite, and providing it all the necessary parameters in real time. The ability to understand the factors that contribute to early equipment failure will result in new operating procedures that will extend the life of the equipment.

[0016] FIG. 5 is a flowchart illustrating a method 120 of hydraulic fracturing, in accordance with example embodiments. It should be noted that the method 120 may include additional steps, fewer steps, and differently ordered steps than illustrated in this example. In this example, a first pressure measurement at a discharge side is obtained (step 122) via a pressure sensor. A second pressure measurement at the discharge side is also obtained (step 124) via the pressure sensor. The first pressure measurement and second pressure measurement may be derived from a pressure sample taken by the pressure sensor over a period of time. In some embodiments, the first pressure measurement is the maximum value in the pressure sample and the second measurement is the minimum value in the pressure sample. In some embodiments, the first pressure measurement and the second measurement represent a pressure fluctuation in the pressure sample. A pressure differential between the first pressure measurement and the second pressure measurement is determined (step 126). An operational condition of the fluid end, such as health or impending failure, is then determined (step 128) based at least in part on the pressure differential. In some embodiments, the operational condition includes an estimation of remaining life of the fluid end. In some embodiments, the pressure differential is negatively correlated with the estimation of remaining life. In some embodiments, the operational condition is determined based on one or more control system data in addition to the pressure differential.

[0017] FIG. 6 includes a diagram 130 illustrating a communications network of the automated fracturing system, in accordance with various embodiments. In this example, one or more hydraulic fracturing components 138, such as, and not limited to, any of those mentioned above, may be communicative with each other via a communication network 140 such as described above with respect to FIG. 3. The components 138 may also be communicative with a control center 132 over the communication network 140. The control center 132 may be instrumented into the hydraulic fracturing system or a component. The control center 132 may be onsite, in a data van, or located remotely. The control center 132 may receive data from any of the components 138, analyze the received data, and generate control instructions for one or more of the components based at least in part on the data. For example, the control center 132 may control an aspect of one component based on a condition of another component. In some embodiments, the control center 140 may also include a user interface, including a display for displaying data and conditions of the hydraulic fracturing system. The user interface may also enable an operator to input control instructions for the components 134. The control center 140 may also transmit data to other locations and generate alerts and notification at the control center 140 or to be received at user device remote from the control center 140.

[0018] Alternate embodiments of the present technology may incorporate the use of alternative cloud services, cloud service providers, or methods of communicating the data from the field (e.g., cellular, satellite, wireless) to accomplish the same ends discussed above. In addition, the machine learning model(s) may be embedded on equipment onsite, such as the various control systems controllers, one of the PCs, or in the IoT gateway. Furthermore, methods other than machine learning may be used to create the prediction algorithms.

[0019] Embodiments may also be described in view of the following clauses:

1. A method of hydraulic fracturing, comprising: providing a fracturing fluid to a pump, the pump comprising a pressure sensor for measuring pressure at a fluid end; injecting the fracturing fluid from the pump into a wellhead via the fluid end; obtaining a first pressure measurement at the fluid end via the pressure sensor; obtaining a second pressure measurement at the fluid end via the pressure sensor; determining a pressure differential between the first pressure measurement and the second pressure measurement; and determining an operational condition of the fluid end based at least in part on the pressure differential and a known or estimated correlation between the pressure differential and the operational condition.

2. The method of clause 1, wherein the first pressure measurement and second pressure measurement are derived from a pressure sample taken by the pressure sensor over a period of time.

3. The method of clause 2, wherein the first pressure measurement is the maximum value in the pressure sample and the second measurement is the minimum value in the pressure sample. 4. The method of clause 2, wherein the first pressure measurement and the second measurement represent a pressure fluctuation in the pressure sample.

5. The method of clause 1, wherein the operational condition includes an estimation of remaining life of the fluid end.

6. The method of clause 5, wherein the pressure differential is negatively correlated with the estimation of remaining life.

7. The method of clause 1, wherein the first and second pressure measurements are taken at a discharge side, a suction side, or a plunger chamber of the fluid end.

8. A method of monitoring a fluid end of a hydraulic fracturing pump, comprising: obtaining a first pressure measurement at the fluid end via a pressure sensor; obtaining a second pressure measurement at the fluid end via the pressure sensor; determining a pressure differential between the first pressure measurement and the second pressure measurement; and determining an operational condition of the fluid end based at least in part on the pressure differential and a known or estimated correlation between the pressure differential and the operational condition. 9. The method of clause 8, wherein the first pressure measurement and second pressure measurement are derived from a pressure sample taken by the pressure sensor over a period of time.

10. The method of clause 9, wherein the first pressure measurement is the maximum value in the pressure sample and the second measurement is the minimum value in the pressure sample.

11. The method of clause 9, wherein the first pressure measurement and the second measurement represent a pressure fluctuation in the pressure sample.

12. The method of clause 8, wherein the operational condition includes an estimation of remaining life of the fluid end.

13. The method of clause 12, wherein the pressure differential is negatively correlated with the estimation of remaining life.

14. The method of clause 8, wherein the operational condition is determined based on one or more control system data in addition to the pressure differential.

15. A hydraulic fracturing system, comprising: a pump comprising a fluid end; a pressure sensor positioned to measure pressure at the fluid end; and a control system, the control system configured to: obtain a first pressure measurement at the fluid end via the pressure sensor; obtain a second pressure measurement at the fluid end via the pressure sensor; determine a pressure differential between the first pressure measurement and the second pressure measurement; and determine an operational condition of the fluid end based at least in part on the pressure differential and a known or estimated correlation between the pressure differential and the operational condition.

16. The system of clause 15, wherein the pressure sensor is a high speed, high pressure transducer.

17. The system of clause 15, wherein the first pressure measurement and second pressure measurement are derived from a pressure sample taken by the pressure sensor over a period of time.

18. The system of clause 17, wherein the first pressure measurement is the maximum value in the pressure sample and the second measurement is the minimum value in the pressure sample. 19. The system of clause 17, wherein the first pressure measurement and the second measurement represent a pressure fluctuation in the pressure sample.

20. The method of clause 15, wherein the operational condition includes an estimation of remaining life of the fluid end.

[0020] The foregoing disclosure and description of the disclosed embodiments is illustrative and explanatory of the embodiments of the invention. Various changes in the details of the illustrated embodiments can be made within the scope of the appended claims without departing from the true spirit of the disclosure. The embodiments of the present disclosure should only be limited by the following claims and their legal equivalents.