51, 61).

In any of the arrangements, the processes (51, 61) can be arranged in separate sections 26, 28 of the machine's chamber 25, such as noted previously and as shown in FIG. 4A. In this instance, the conditioning process (51) in the first section 26 imparts the media (M) at the conditioning intensity at the sucker rod 10 as the sucker rod 10 is fed into the chamber 25. The advancing sucker rod 10 with the conditioned surfaces then passes to the second section 28, and the shot peening process (61) imparts the media (M) at the shot peening intensity at the sucker rod 10, as the sucker rod 10 leaves the chamber 25.

Alternatively, the processes (51, 61) can be distributed in the machine's chamber 25, as shown in FIG. 4B. In this instance, the conditioning process (51) can be performed for an initial time period as the sucker rod 10 is fed into and moved back and forth in the chamber 25. The shot peening process (61) can then be performed at a subsequent time period while the sucker rod 10 is moved back and forth in the chamber 25 and while the conditioning process (51) is stopped. Further impacts can be provided during the shot peening process (61) by also operating the conditioning process (51) at the same time as the shot peening process (61). Yet, according to the teachings disclosed herein, the conditioning process (51) is operated to initially condition the surfaces of the sucker rod 10 so the shot peening process (61) can subsequently treat the conditioned surfaces of the sucker rod 10.

As noted above, the handling unit 30 can move/manipulate the sucker rods 10, and the machine (20) can operate to produce even coverage for the conditioning and shot peening processes 51, 61. For example, FIG. 5A schematically illustrates an end view of a sucker rod 10 relative to an accelerator source 90 directed at the sucker rod 10 to perform one of the subject conditioning/shot peening processes. The handling unit 30 can rotate the sucker rod 10 relative to the accelerator source 90 to increase coverage of the subject process.

As schematically shown in FIG. 5B, more than one accelerator source 90a-c at different orientations can be directed at the sucker rod 10 to increase coverage of the subject process. Here, three accelerator sources 90a-c are arranged at 120-degrees about the sucker rod 10, but more or fewer accelerator sources 90a-c can be used and can be arranged at any number of acceptable orientations. Additionally, FIG. 5C shows how multiple accelerator sources 90a-b can be used in conjunction with rotation of the sucker rod 10 to increase coverage for the subject process.

As noted above, both the conditioning and shot peening processes (51, 61) use the same media M to impact the surfaces of the sucker rods 10, but the shot peening process (61) uses a shot peening intensity that is greater than the conditioning intensity of the conditioning process (51). For further understanding, example shot peen intensity results are provided in the chart of FIG. 6 for various sucker rod diameters and grades. The examples are listed for sucker rods having diameters ranging from ⅝ in. to 2 in. For each of the listed diameters, the shot peen intensity results are provided for four sucker rod grades (Grade 1, 2, 3, and 4), which are divided according to ranges of hardness grades given in Rockwell C reference (HRC) according to ASTM E18-22.

The shot peen intensity results are provided in ranges of minimum and maximum shot peens produced on the respective sucker rods using the shot peening process (61) according to the disclosed techniques. The values for the minimum and maximum shot peens are given in arc height (inches) using Almen strips type A (regular hardness) according to AMS2430 and SAE J443. The conditioning process (51) can be controlled to have lower intensity, producing results that range from about 5% to 50% of the results of the shot peening process (61).

As discussed herein, process parameters providing process intensity of the shot peening process (61) can include media (e.g., type and size), media flow rate (lbs/min), wheel speed (RPM), linear speed (ft/min) used to handle the sucker rod, and the like. The shot peening process' parameters are configured to produce the example shot peen intensity results listed in FIG. 6. As a corollary, the conditioning process' parameters include the same media (e.g., type and size), but include differences in one or more of media flow rate (lbs/min), wheel speed (RPM), linear speed (ft/min), or the like. The conditioning process' parameters are configured to produce condition intensity results that are about 5% to 50% of the shot peen intensity results listed in FIG. 6.

As one example, for a sucker rod of Grade 2 (22-30 HRC) having a 1-in. diameter, the shot peen intensity result can have an arc height ranging from about 0.006 to 0.022 in. According to the corollary, the condition intensity result can have “theoretical” results that range from between 0.0003 to 0.0011 in. (5%) and 0.003 to 0.011 in. (50%). As will be appreciated, the “theoretical” results may not actually be produced and may not even be measurable. Instead, the conditioning process' parameters are calculated and controlled to at least theoretically produce such “theoretical” results as compared to the example shot peen intensity results shown here. Yet, the conditioning process (51) is designed to condition the rod surfaces for the shot peening.

Returning to FIGS. 3A-3B, the shot peening process (61) can increase the fatigue strength of the sucker rods 10. To do this, the shot peening process (61) imparts (bombards) the surface of the sucker rod 10 with the small media (shots) M at high velocity. The impacts create a compressive residual stress layer and modify the mechanical properties of the material of the sucker rods 10. The types and sizes of media M used in the shot peening process (61) can be selected to meet desired surface characteristics and to provide a defined surface finish and strength.

The types of media M that can be used include steel shot, glass beads, ceramic beads, and cut wire shot. Steel shot, being the most common media used for shot peening sucker rods, can have sizes ranging from about S70 (very fine) to S780 (coarser) measured in screen mesh. Glass beads can provide a less aggressive peening action than steel shot and can be effective in cleaning and slightly peening the surface without removing much material. Ceramic beads can be harder and can have a more consistent size and shape compared to glass beads. Therefore, the ceramic beads can provide more control in the peening process. The ceramic beads are harder and more consistent in size and shape compared to glass beads, offering a uniform peening action. Finally, cut wire shot consists of cylindrical particles formed by cut wire having lengths about equal to the wire diameter. The cut wire shot can be made of steel, stainless steel, or other metals and can provide a consistent, repeatable peening action.

The size of the media M defines aspects of the intensity and coverage of the shot peening process (61), and by corollary, the intensity and coverage of the conditioning process (51). As expected, smaller media M can provide a smoother finish but may require more time to achieve the desired level of residual stress. Also, larger media M can cover a larger surface area more quickly but might not provide a desired finish.

Accordingly, the media M used for shot peening the sucker rods 10 is selected based on coverage, intensity, the material of the sucker rods 10, the desired finish, and the desired level of residual stress to be produced. Because the media M is also used for the conditioning process (51) by the conditioning unit 50, the media M is also selected to not only meet the requirements of the shot peening process (61), but also to meet intensity, coverage, the surface conditions of the sucker rods 10 to be conditioned.

As noted in the background of the present disclosure, shot peening using a standard machine can perform only blasting or peening to process the sucker rods passing through the machine. Thus, to perform shot peening on sucker rods having surface impurities, some portion of the shot peening goes into removing the impurities, which dampens the shot peening intensity, reduces the shot peening penetration, and compromises any resultant compressive residual stress achieved.

In summary, the machine 20 disclosed herein, however, includes two processes to treat the sucker rods 10. The first process performs rod conditioning, which can be performed in a first section 26 having a conditioning unit 50, to condition unconditioned surface of the sucker rods. The second process performs shot peening, which can be performed in a second section 28 having a shot peening unit 60 on the conditioned surface, to produce a surface finish and fatigue strength. The rod conditioning is performed by one or more conditioning accelerators 52 or wheels 54 operated with lower intensity—i.e., lower available kinetic energy than the shot peening process (61) of the machine 20. The rod conditioning process (51) is configured to remove any surface impurities before the shot peening process (61).

The shot peening is performed by one or more shot peening accelerators 62 or wheels 64, which are operated with the desired intensity, higher than the intensity of the conditioning process (51). This shot peening process (61) has a quality/performance requirement associated with a determined intensity and saturation value. For example, the quality/performance requirements for the shot peening of the sucker rods 10 can be defined by the specifications AMS2430 and SAE J443. The coverage for the shot peening of the sucker rods 10 may provide a minimum coverage (e.g., 98% of “full” coverage), such as defined in the specification AMS 2430 and SAE J2277.

The media M in use for the rod conditioning process (51) is the same as that used in the shot peening process (61). Accordingly, only one single size and type of media M is used for both rod conditioning and shot peening in the machine 20. This makes the machine 20 much less expensive and easier to implement. Moreover, the quality control and reclamation process for the media M can comply with the requirements of the shot peening process (61).

The combined machine 20 and processes (51, 61) provides a number of advantages. The disclosed machine 20 and processes (51, 61) prevent the shot peening intensity (available energy) from being wasted in cleaning the sucker rods 10 instead of creating the desired residual compressive stress on the rod's surface. The combined machine 20 and processes (51, 61) allow conditioning and peening to be performed with less equipment. Additionally, using a single media M for both processes (51, 61) can simplify the media reclamation and handling equipment, making them more cost-effective.

FIG. 7 illustrates a process 100 to treat sucker rods 10 according to the present disclosure. The process 100 can include initially cleaning the sucker rods 10 (e.g., recently manufactured and/or used rods) in a cleaning process (Block 102). Visual inspection can be performed of the sucker rods 10 to detect any damage (Block 104). Metallurgical inspection of the metallic material of the sucker rods 10 can also be performed to detect any defects that may not be visible (Block 106). Damaged sucker rods 10 that cannot be repaired can be discarded.

With the sucker rods 10 ready to be treated, the sucker rods 10 are handled in a machine to treat the sucker rods 10 (Block 108). For example, the machine 20, such as disclosed above with reference to FIGS. 3A-3B, can be used. Handling the sucker rods 10 in the machine 20 can be performed by robotically moving the sucker rods 10 in the machine 20. A conveyor, robotic mechanism, or other type of motorized mechanism can be used for the handling unit 30.

Surfaces of the sucker rods 10 are conditioned in a conditioning process (51) to produce conditioned surfaces (Block 110). The control unit 80 controls one or more first media accelerators 52 operated in the machine 20 (Block 112) to impart media M of a defined type and size at a first intensity at the sucker rods 10 (Block 114). The conditioned surfaces of the sucker rods 10 are then shot peened in a shot peening process (61) in the machine 20 (Block 120). The control unit 80 controls one or more second media accelerators 62 operated in the machine 20 (Block 122) to impart the media M of the same defined type and defined size at a second intensity at the sucker rods 10 (Block 124). The second intensity is greater than the first intensity.

There are several features of the media accelerators 52, 62 that can provide the different intensities required for the conditioning and shot peening processes (51, 61). One or more of the following aspects can be used alone or in combination to achieve the purposes of the present disclosure. As noted, the one or more first media accelerators 52 can include one or more first wheels 54 driven by drive(s) 55 in the conditioning unit 50, and the one or more second media accelerators 62 can include one or more first wheels 54 driven by drive(s) 65 in the shot peening unit 60.

In one aspect, more shot peening wheels 64 can be used compared to the conditioning wheels 54 to achieve a greater intensity. Therefore, additional amounts of media M can be imparted by the shot peening wheels 64 compared to the conditioning wheels 54 with all other parameters being equal. In additional aspects, the shot peening wheels 64 can have a larger diameter than the conditioning wheels 54 to produce a greater media velocity, the shot peening wheels 64 can be rotated at a faster rotational speed than the conditioning wheels 54 to produce a greater media velocity, and/or the shot peening wheels 64 can be fed and impart a greater amount of media M than the conditioning wheels 54 to produce more impacts. In this way, the shot peening wheels 64 can provide increased velocity and/or coverage of the media M imparted against the surfaces of the sucker rods 10.

The media M from the conditioning and shot peening processes (51, 61) is then reclaimed in the machine 20 (Block 130). The reclaimed media from the conditioning and shot peening processes (51, 61) can then be reused in either one or both of the conditioning process (51) and the shot peening process (61).

FIG. 8 schematically illustrates components of a processing device or control unit 80 (e.g., central PLC control system), which can correspond to the control unit 80 of FIG. 3B. As shown, the control unit 80 can include a bus 81, a processor 82, a memory 83, an input component 84, an output component 85, and a communication interface 86.

The bus 81 includes one or more components that enable wired and/or wireless communication among the components of the control unit 80. The bus 81 can couple together two or more components of FIG. 3B, such as via operative coupling, communicative coupling, electronic coupling, and/or electric coupling. The processor 82 includes a central processing unit, a graphics processing unit, a microprocessor, a controller, a microcontroller, a digital signal processor, a field-programmable gate array, an application-specific integrated circuit, and/or another type of processing component. The processor 82 is implemented in hardware, firmware, or a combination of hardware and software. In some implementations, the processor 82 includes one or more processors capable of being programmed to perform one or more operations or processes described elsewhere herein.

The memory 83 includes volatile and/or nonvolatile memory. For example, the memory 83 can include random access memory (RAM), read only memory (ROM), a hard disk drive, and/or another type of memory (e.g., a flash memory, a magnetic memory, and/or an optical memory). The memory 83 can include internal memory (e.g., RAM, ROM, or a hard disk drive) and/or removable memory (e.g., removable via a universal serial bus connection). The memory 83 can be a non-transitory computer-readable medium. The memory 83 stores information, instructions, and/or software (e.g., one or more software applications) related to the operation of the control unit 80. In some implementations, the memory 83 includes one or more memories that are coupled to one or more processors (e.g., the processor 82), such as via the bus 81.

The input component 84 enables the control unit 80 to receive input, such as user input and/or sensed input. For example, the input component 84 can include a touch screen, a keyboard, a keypad, a mouse, a button, a microphone, a switch, a sensor, an accelerometer, a gyroscope, and/or an actuator. The output component 85 enables the control unit 80 to provide output, such as via a display, a speaker, and/or a light-emitting diode. The communication interface 86 enables the control unit 80 to communicate with other devices via a wired connection and/or a wireless connection. For example, the communication interface 86 can include a receiver, a transmitter, a transceiver, a modem, a network interface card, and/or an antenna.

The control unit 80 can perform one or more operations or processes described herein. For example, a non-transitory computer-readable medium (e.g., the memory 83) can store a set of instructions (e.g., one or more instructions or code) for execution by the processor 82. The processor 82 can execute the set of instructions to perform one or more operations or processes described herein. In some implementations, execution of the set of instructions, by one or more processors 82, causes the one or more processors 82 and/or the control unit 80 to perform one or more operations or processes described herein. In some implementations, hardwired circuitry can be used instead of or in combination with the instructions to perform one or more operations or processes described herein. Additionally, or alternatively, the processor 82 can be configured to perform one or more operations or processes described herein. Thus, implementations described herein are not limited to any specific combination of hardware circuitry and software.

For instance, the control unit 80 can receive inputs via the input component 84. These inputs can include one or more characteristics associated with the sucker rods (10) to be treated, such as the type of the sucker rods (e.g., new or used) to be treated, a condition of the sucker rod (e.g., type and/or extent of scale, rust, surface impurities, etc.), a material of the sucker rods (e.g., type of steel, hardness grade, etc.), dimensions of the sucker rods (e.g., length, diameter, etc.), and any other details of the sucker rods. The inputs can also include desired results from the treatment of the sucker rods (10), such as desired surface finish, desired fatigue strengthening, and the like.

In one configuration, the processor 82 can also receive inputs that are used to control operation of the machine (20), such as parameters for the type of media (M) being used, the size of the media (M) being used, the intensity of the conditioning process (51) to be performed, and the intensity of the shot-peening process (61) to be performed. The processor 82 can use the inputs to coordinate the conditioning process (51) and the shot peening process (61) by controlling the drives (e.g., 35, 55, 65 of FIG. 3B) to achieve the desired results for the characterized sucker rods (10) being treated.

In another configuration, the processor 82 can use the input characteristics and the input results to select/calculate/determine/configure the operational parameters to control the machine. In an automated process, for example, the processor 82 can select the operational parameters, such as a defined type of media (M) to be used, a defined size of the media (M) to be used, an intensity to be performed in the conditioning process (51), and an intensity to be performed in the shot peening process (61). The selection/calculation/determination/configuration for the operational parameters can be stored in lookup tables, logic, equations, and the like stored in memory 83 and based on calibrated and programmed data. The processor 82 can use these selected parameters as programmable variable to coordinate the conditioning process (51) and the shot peening process (61) by controlling the drives (e.g., 35, 55, 65 of FIG. 3B) to achieve the desired results for the characterized sucker rods (10) being treated.

In both the conditioning and shot peening processes (51, 61) as noted above, some examples of the parameters that can be manipulated and selected to control the intensity and/or coverage include the media flow rate (lbs/min), wheel speed (RPM), and the linear speed (ft/min) used by the handling unit (30) (e.g., conveyor or the like) to handle the sucker rods (10). Each of these parameters can be controlled by the control unit 80.

The number and arrangement of components shown in FIG. 8 are provided as an example. The control unit 80 can include additional components, fewer components, different components, or differently arranged components than those shown in FIG. 8. Additionally, or alternatively, a set of components (e.g., one or more components) of the control unit 80 can perform one or more functions described as being performed by another set of components of the control unit 80.

As used herein, the term “rod” and “sucker rod” can include hollow or solid rods, continuous rods, joints, or the like. The term “rod” can include welded, flanged, screwed, and other rod goods. In particular, joints of sucker rods used in artificial rod lift systems are one type of rod that can benefit from the techniques described herein, but the disclosure is not so limited. As used herein, the term “used rod” and “used sucker rod” can mean a rod that has been in actual service in the filed for a purpose, such as lifting fluids by connecting a downhole pump to a surface driver. As used herein, the term “new rod” and “new sucker rod” can mean a rod that has been manufactured in a facility or can mean a rod that has been previously used but has been remanufactured, reconditioned, or repaired for use again in the field.

Configurations of the present disclosure can be characterized by the following clauses:

- Clause 1. A machine (20) to treat sucker rods (10), the machine (20) comprising: a controller (80); a chamber (25); handling equipment (30) being configured to handle the sucker rods (10) in the chamber (25) of the machine (20); conditioning equipment (50) in operational communication with the controller (80) and being configured to condition unconditioned surfaces of the sucker rods (10) in a conditioning process (51) to produce conditioned surfaces, the conditioning equipment (50) having one or more first media accelerators (52) being configured to impart media (M) of a defined type and a defined size at a first intensity at the sucker rods (10) in the chamber (25); and shot peening equipment (60) in operational communication with the controller (80) and being configured to shot peen the conditioned surfaces of the sucker rods (10) in a shot peening process (61) following the conditioning process (51), the shot peening equipment (60) having one or more second media accelerators (62) being configured to impart the media (M) of the defined type and the defined size at a second intensity at the sucker rods (10) in the chamber (25), the second intensity being greater than the first intensity.
- Clause 2. The machine (20) of clause 1, wherein the one or more first media accelerators (52) comprise one or more first wheels (54); and wherein the one or more second media accelerators (62) comprise one or more second wheels (64).
- Clause 3. The machine (20) of clause 2, wherein the one or more first wheels (54) have a first diameter; and wherein the one or more second wheels (64) have a second diameter, the second diameter being greater than the first diameter.
- Clause 4. The machine (20) of clause 2 or 3, wherein the one or more first wheels (54) are rotated at a first rotational speed; and wherein the one or more second wheels (64) are rotated at a second rotational speed, the first rotational speed being greater than the first rotational speed.
- Clause 5. The machine (20) of clause 2, 3 or 4, wherein the one or more first wheels (54) impart a first amount of the media (M) within a given time period; and wherein the one or more second wheels (64) impart a second amount of the media (M) within the given time period, the second amount being greater than the first amount.
- Clause 6. The machine (20) of any one of clauses 1 to 5, wherein at least one of: the one or more second media accelerators (62) are configured to impart the media (M) at a second speed, the second speed being greater than a first speed imparted by the one or more first media accelerators (52); the one or more second media accelerators (62) are configured to impart a second amount of the media (M) within a given time period, the second amount being greater than a first amount imparted by the one or more first media accelerators (52) within the given time period; the one or more second media accelerators (62) are configured to impart the media (M) for a second time period, the second time period being greater than a first time period for the one or more first media accelerators (52); and a second number of the one or more second media accelerators (62) being greater than a first number of the one or more first media accelerators (52) in the machine (20).
- Clause 7. The machine (20) of any one of clauses 1 to 6, wherein the handling equipment (30) comprises a motorized mechanism in operational communication with the controller (80) and being configured to move the sucker rods (10) in the machine (20).
- Clause 8. The machine (20) of clause 7, wherein the motorized mechanism comprises a plurality of rollers (32, 34), a pair of grippers (36), or a conveyor (38) in the machine (20).
- Clause 9. The machine (20) of any one of clauses 1 to 8, wherein the handling equipment (30) is configured to move the sucker rods (10) at a same length per unit time in both the conditioning process (51) and the shot peening process (61).
- Clause 10. The machine (20) of any one of clauses 1 to 9, further comprising a media recovery equipment (70) configured to reclaim the media (M) from the conditioning process (51) and the shot peening process (61) in the machine (20).
- Clause 11. The machine (20) of any one of clauses 1 to 10, wherein the controller (80) is configured to coordinate the conditioning process (51) and the shot peening process (61) relative to one or more characteristics of the sucker rods (10).
- Clause 12. The machine (20) of clause 11, wherein to coordinate the conditioning process (51) and the shot peening process (61), the controller (80) is programmable based on one or more of: a first parameter selected for the defined type of the media (M), a second parameter selected for the defined size of the media (M), a third parameter selected for the first intensity used in the conditioning process (51), and a fourth parameter selected for the second intensity used in the shot peening process (61).
- Clause 13. The machine (20) of clause 11 or 12, wherein to coordinate the conditioning process (51) and the shot peening process (61), the controller (80) is programmable based on a length per unit time selected to move the sucker rods (10) in the machine (20) for both the conditioning process (51) and the shot peening process (61).
- Clause 14. The machine (20) of any one of clauses 1 to 13, wherein the controller (