Retaining Kit for Securing a Port Nut

Description

TECHNICAL FIELD

The present disclosure relates generally to a retaining kit for securing a port nut, and more particularly to a retaining kit for securing a hydraulic pump port nut within a pump block.

BACKGROUND

Bedrock fracturing units commonly include hydraulic pumps which pump liquids or slurries during a hydraulic fracturing process. The hydraulic pumps generally first pump the liquid or slurry into the bedrock formation until it is full, and then pressurize the liquids or slurries to pressures high enough to fracture the bedrock formation. Due to the high pressures generated by the hydraulic pumps, which may be in excess of 20,000 PSI, they are regularly opened, inspected, and serviced. Accordingly, the hydraulic pumps generally include servicing ports which provide access to the various internal components.

After servicing a hydraulic pump, the servicing ports are generally sealed off by placing a plug within each servicing port and then threading a port nut into each servicing port, the port nuts holding the plugs in position. While in use, the hydraulic pump may experience high pressures as well as vibration, either of which may loosen the port nuts within the servicing ports, and this may cause the plugs to shift and the hydraulic pump to leak. In some situations, the port nut may be loosened in a manner that can structurally impact or damage the servicing port, such as flattening the threads that hold the port nut in place. Depending on the extent of damage to the servicing port, the entire hydraulic pump may need to be removed from service.

U.S. Pat. No. 8,402,880B2 describes a locking assembly for a servicing port. The assembly of the '880 patent includes a plug and a port nut which are positioned within a threaded servicing port. The port nut has external threads which engage the threads of the bore, and further includes a central opening. A locking member is inserted into the central opening and a fastener secures the locking member to the plug, preventing rotation of the port nut relative to the plug.

The locking assembly in the '880 patent represents one possible approach, but additional future designs might present other choices for securing a port nut within a pump block.

SUMMARY

In an aspect of the present disclosure, there is a bedrock fracturing unit, including a pump block, a plug, a port nut, a flange, and a flange nut. The pump block includes an exterior surface with a port therethrough, the port including an internal shoulder and a threaded internal surface. The plug is configured to seat against the internal shoulder. The port nut includes a first threaded radial surface configured to engage the threaded internal surface, a top surface, and a bottom surface opposite the top surface, the bottom surface configured to compress the plug against the internal shoulder when the port nut is engaged with the threaded internal surface. The flange includes an outer surface, a central aperture defining a threaded inner surface, the inner surface opposite the outer surface, and a plurality of mounting holes configured to mount the flange to the exterior surface of the pump block such that the port nut is accessible through the central aperture. The flange nut includes a top side, a bottom side opposite the top side, the bottom side configured to engage the top surface, and a second threaded radial surface configured to engage the threaded inner surface.

In another aspect of the present disclosure, there is a kit for securing a port nut in a pump block of a bedrock fracturing unit, the pump block having an external surface and a threaded cavity opening to the external surface, the port nut having a first threaded outer surface configured to mate with the threaded cavity. The kit includes a flange configured to be mounted to the external surface of the pump block and having a threaded opening and a flange nut having a second threaded outer surface configured to mate with the threaded opening of the flange. The first threaded outer surface has a first thread pitch, and the second threaded outer surface has a second thread pitch, the first thread pitch being different from the second thread pitch. After the port nut is secured within the threaded cavity and the flange is connected to the pump block, the flange nut is threaded into the flange until it engages the port nut.

In yet another aspect of the present disclosure, a method is provided for securing a port nut within a pump block of a bedrock fracturing unit. The method includes threading the port nut into a threaded cavity of the pump block, the port nut having a first thread pitch. The method further includes securing a flange to an external surface of the pump block, the flange having a threaded opening, the threaded opening generally surrounding the threaded cavity of the pump block. The method finally includes threading a flange nut into the threaded opening of the flange and into contacting relationship with the port nut, the flange nut having a second thread pitch different from the first thread pitch of the port nut.

Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a side view depicting a bedrock fracturing unit that provides fluid to a valve.

FIG. 2 is a side view of a hydraulic pump of the bedrock fracturing unit of FIG. 1, showing an uncovered service port and a plurality of covered service ports.

FIG. 3 is a side sectional view of one of the covered service ports taken along the line III-III in FIG. 2.

FIG. 4 is an isometric view of a retaining kit used to further secure a covered service port.

FIG. 5 is an exploded view of the service port of FIG. 3, further including sectional views of the retaining kit of FIG. 4.

FIGS. 6A-6E depict the installation of a cover and retaining kit into a service port.

FIG. 7 shows a hydraulic pump setup with each of the service ports at a different installation step.

DETAILED DESCRIPTION

FIG. 1 shows a bedrock fracturing unit 100 connected between a fluid tank 102 and a valve 104. The valve 104 is connected to an underground pipe which extends into a bedrock formation deep within the earth. The bedrock fracturing unit 100 includes a hydraulic pump 106 which receives fluid from the fluid tank 102. To drive the pump 106, the bedrock fracturing unit 100 also includes an engine 108 connected to the pump. As the engine 108 drives the pump 106, the pump 106 sends fluid through the valve 104 and into the bedrock formation, filling it with the fluid. The engine 108 continues to drive the pump 106 after the bedrock formation is filled with the fluid, which increases the pressure within the bedrock formation until the bedrock formation fractures. To keep the engine 108 cool during this process, the bedrock fracturing unit 100 further includes a cooling system 110 connected to the engine 108.

Although the engine 108 is illustrated as an internal combustion engine, the engine 108 may be a dual fuel or turbine engine, electric motor, and/or other engine or device designed to drive the pump 106. Further, the cooling system 110 may be different and/or removed from the bedrock fracturing unit 100 depending on the engine 108.

FIG. 2 shows the hydraulic pump 106, noted in the dashed line box labeled “II” in FIG. 1. The hydraulic pump 106 generally includes a pump block 200, a plurality of port nuts 202, an inlet pipe 204, and an outlet pipe 206.

The pump block 200 is a steel casing which houses many of the components of the hydraulic pump 106. The pump block 200 includes an external surface 208, a plurality of ports 210, and a plurality of pumping chambers 212. The external surface 208 is shown as the surface the ports 210 extend through, however the external surface 208 may be any surface which defines at least a portion of the outside of the pump block 200.

The ports 210 are each a passageway that extends outward from one of the pumping chambers 212 and through the external surface 208. The ports 210 provide access to the pumping chambers 212 from the outside of the pump block 200. The ports 210 are sized such that the components within the pumping chambers 212 may be inspected and/or serviced through the ports 210.

The pumping chambers 212 are each separate cavities within the pump block 200 and are each fluidly connected to one of the ports 210. The pumping chambers 212 are where the fluid is pressurized within the pump block 200 and include various pumping components and passageways.

The port nuts 202 are threaded nuts which connect to the ports 210 and may be used to close or restrict access to the pumping chambers 212. The pump block 200 is shown with five ports 210, with the leftmost port 210 uncovered and the other four ports 210 each covered by a port nut 202.

The inlet pipe 204 is a pipe connected to the pump block 200 and the fluid tank 102. The inlet pipe 204 carries fluid to the pump block 200 to be pressurized. The inlet pipe 204 is fluidly connected to each of the pumping chambers 212, such that the fluid may be dispersed to each.

The outlet pipe 206 is another pipe and is connected to the pump block 200 and the valve 104. The outlet pipe 206 is fluidly connected to each of the pumping chambers 212, and carries the pressurized fluid exiting each pumping chamber 212 to the valve 104.

FIG. 3 shows a sectional view of the pump block 200 taken through the dashed line labeled III-III in FIG. 2. One of the pumping chambers 212 is shown connected to the outside of the pump block 200 through one of the ports 210.

The port 210 includes a first segment 300, a shoulder 302, and a second segment 304. The first segment 300 extends to the external surface 208, includes a threaded section 306, and is larger in diameter than the second segment 304. The shoulder 302 connects the first segment 300 to the second segment 304 and is where the diameter of the port 210 is decreased from the diameter of the first segment 300 to the diameter of the second segment 304. The second segment 304 is smooth and is open to the pumping chamber 212.

The port 210 is closed by a plug 308 and a port nut 202. The plug 308 includes a main body 310, a seal 312, and a brim 314. The main body 310 fits within second segment 304 of the port 210 and includes a slot 311, extending around the outside thereof. The seal 312 is compressible and fits within the slot 311. The seal 312 shown is compressed such that it is pressed between the surface of the second segment 304 and the slot 311, creating a seal between the second segment 304 and the plug 308. The brim 314 is located at an end of the plug 308 and has a larger diameter than the second segment 304 such it contacts the shoulder 302 of the port 210 and prevents the plug 308 from moving inwardly through the second segment 304 toward the pumping chamber 212.

The port nut 202 includes a threaded radial surface 316, a bottom surface 318, a top surface 320, a ledge 322, a land 324, and a tool aperture 326. The threaded radial surface 316 engages the threaded section 306 of the port 210 to connect the port nut 202 to the port 210. The bottom surface 318 is shown contacting the brim 314. The top surface 320 is opposite from and is the surface furthest from the bottom surface 318. The ledge 322 is between the top surface 320 and the land 324. The land 324 is between the ledge 322 and the threaded radial surface 316 and extends circumferentially around the top surface 320. The tool aperture 326 is a hole which extends from the top surface 320 to the bottom surface 318 and is configured to accept a tool used to thread the port nut 202 with respect to the port 210. For example, the tool aperture may have six sides and be configured to receive an allen-type wrench or hex-bit socket for turning the port nut 202.

FIG. 4 shows a retaining kit 400. The retaining kit 400 includes a flange 402 and a flange nut 404.

The flange 402 includes a mounting face 406, a back face 408, a central aperture 410, a threaded inner surface 412, an outer surface 414, and a plurality of mounting holes 416. The mounting face 406 is opposite the back face 408 and is configured to mate with the external surface 208 of the pump block 200. The central aperture 410 extends through the back face 408 and the mounting face 406 and defines the threaded inner surface 412. The outer surface 414 is radially outside of the threaded inner surface 412. The plurality of mounting holes 416 each extend through the mounting face 406 and the back face 408 and are configured to accept fasteners 502 (as described below with respect to FIG. 5). The mounting holes 416 are shown spaced circumferentially around the central aperture 410 and between the threaded inner surface 412 and outer surface 414.

The flange nut 404 includes a circumferential surface 418, a bottom face 420, a top face 422, and a tool hole 424. The circumferential surface 418 includes a threaded segment 426 and a plurality of tool bores 428. The threaded segment 426 extends from the bottom face 420 towards the top face 422 and engages the threaded inner surface 412 of the flange 402 to connect the flange nut 404 to the flange 402. The tool bores 428 extend radially inwards from the circumferential surface 418 and are configured to accept a tool used to rotate the flange nut 404 with respect to the flange 402. The tool bores 428 are shown located between the threaded segment 426 and the top face 422 and are spaced from one another around the circumferential surface 418.

The bottom face 420 is opposite the top face 422 and includes a ring 432 which defines a cavity 430. The cavity 430 extends axially inwards from the bottom face 420 and is sized such that a portion of the port nut 202, including its top surface 320, may fit within the cavity 430. The ring 432 protrudes axially outwards from the bottom face 420 and extends circumferentially around the cavity 430. The ring 432 is configured to engage the land 324 of the port nut 202. The tool hole 424 extends through the top face 422 and bottom face 420, the tool hole 424 configured to accept a tool used to rotate the flange nut 404 with respect to the flange 402.

Although shown having a circular outer surface 414, the outer surface 414 of the flange 402 may be any number of shapes. Further, although the ring 432 is shown as a single piece, the ring 432 may be a series of protrusions spaced circularly around the bottom face 420. In some cases, the bottom face 420 may not include the ring 432 and/or the cavity 430. Additionally, there may be any number of fasteners 502, the fasteners 502 having any number of various shapes and/or sizes.

FIG. 5 and FIGS. 6A-6E each show a sectional view of the pump block 200 having port 210, plug 308, port nut 202, flange 402, and flange nut 404. FIG. 5 shows these components laid out in installation order, while FIGS. 6A-6E show a progression of their assembly together.

Turning to FIG. 5, the pump block 200 is shown including a plurality of mounting bores 500. The mounting bores 500 are threaded cavities that extend through the external surface 208 and into the pump block 200. The mounting bores 500 may be machined into the pump block 200 prior to or during assembly of the retaining kit 400 onto the pump block 200. Further, a plurality of fasteners 502 are shown, illustrated as bolts. The fasteners 502 are configured to partially pass through the mounting holes 416 of the flange 402 and connect to the mounting bores 500, pressing the flange 402 against the external surface 208 of the pump block 200.

As for the installation order of the components, the components are laid out left-to-right in order of installation in FIG. 5. More detail on the installation of their various components is presented in FIGS. 6A-6E. The mounting bores 500 may be located and machined at any point prior to installation of the flange 402.

The plug 308 is shown as the first component to be installed, with the plug 308 inserted into the port 210 past the external surface 208 and first segment 300, and generally into the second segment 304. The port nut 202 is shown as the second component to be installed, with the port nut 202 threaded into the threaded section 306 of the port 210 until it contacts the plug 308. The flange 402 is shown as the third component to be installed, with a portion of the fasteners 502 passing through the mounting holes 416 and threading into the mounting bores 500 until the flange 402 is pressed against the external surface 208. The flange nut 404 is shown as the fourth component to be installed, the flange nut 404 threaded into the threaded inner surface 412 of the flange 402 until it contacts the port nut 202.

To assist with restricting the rotation of the port nut 202 when the flange nut 404 is installed, the port nut 202 and flange nut 404 have differing thread pitches. As shown, the threaded radial surface 316 of the port nut 202 (and corresponding threaded section 306 of the port 210) has a coarser thread than the threaded segment 426 of the flange nut 404 (and corresponding threaded inner surface 412 of the flange 402). Threading may be fine or coarse, with a coarse thread having a pitch which is larger than a fine thread, leading to less threads per inch. With a different thread pitch, rotation of the port nut 202 out of the port 210 does not rotate the flange nut 404 at the same rate, creating resistance.

For example, the threaded radial surface 316 may be three threads per inch, and the threaded segment 426 may be eight threads per inch, with each having the same-hand threading. In order to rotate out an inch, the threaded radial surface 316 needs to rotate three times while rotating the threaded segment 426 eight times. As such, the threaded radial surface 316 backs out further than the threaded segment 426 per rotation. However, since the port nut 202 and flange nut 404 are pressed together when installed, they both initially try to rotate at the same time. Since the threaded radial surface 316 attempts to move further than the threaded segment 426, such an attempt at rotation would further press them together and create additional resistance to rotation.

However, there may be many variations of the threading on one or more of the components. For example, the port nut 202 or flange nut 404 may have right-hand threading, while the other has left-hand threading. Accordingly, attempted loosening of the port nut 202 may instead tighten the flange nut 404. Further, depending on particular use, different thread pitches or pitch differences may be desired. For example, some uses may desire at least a two-thread-per-inch pitch difference between the port nut 202 and flange nut 404. In other uses, the pitch of the port nut 202 may be between one and four threads per inch, while the pitch of the flange nut 404 may be between five and ten threads per inch.

FIGS. 6A-6E show a progression of the components discussed in FIG. 5 installed into the pump block 200. FIGS. 6A-6C show the installation of the plug 308 and port nut 202, which closes the port 210. FIGS. 6D-6E show the installation of the retaining kit 400, which secures the port nut 202 within the port 210. Together, FIGS. 6A-6E show the port 210 closed and secured such that the pump block 200 may be put into service.

Turning to FIG. 6A, the pump block 200 is shown with an empty port 210 such that the pumping chamber 212 is accessible through the port 210. As shown, there is nothing within or otherwise connected to the first segment 300 or second segment 304. This generally would be the state of the port 210 immediately prior to or after servicing the pumping chamber 212.

FIG. 6B shows the plug 308 installed generally within the second segment 304. The main body 310 is within the second segment 304 with the seal 312 pressed against the surface of the second segment 304, creating a seal between the plug 308 and the second segment 304. The brim 314 is in contact with the shoulder 302 and is within the first segment 300, restricting the plug 308 from moving further into the second segment 304 in the direction of the pumping chamber 212.

FIG. 6C shows the port nut 202 installed within the first segment 300. The threaded radial surface 316 of the port nut 202 is engaged with the threaded section 306 of the first segment 300. The bottom surface 318 of the port nut 202 is in contact with the brim 314, pressing the brim 314 against the shoulder 302 and restricting the plug 308 from moving out of the second segment 304 in the direction of the first segment 300. The land 324 is shown generally in line with the external surface 208, with the top surface 320 extending outside of the pump block 200, proud of the external surface 208.

FIG. 6C shows the plug 308 and port nut 202 installed within the pump block 200, which closes and seals the port 210. FIGS. 6D-6E show the retaining kit 400 installed onto the pump block 200, which assists with holding the plug 308 and port nut 202 in their installed position.

FIG. 6D shows the flange 402 installed onto the pump block 200. The mounting holes 416 are lined up with the mounting bores 500, and the fasteners 502 have been passed through the mounting holes 416 and engaged with the mounting bores 500. The fasteners 502 press the flange 402 against the pump block 200 such that the entire mounting face 406 is flush with and contacting the external surface 208. However, the flange 402 does not contact the port nut 202. Rather the central aperture 410 surrounds the port nut 202 such that the tool aperture 326 is accessible through the central aperture 410, and the port nut 202 may be adjusted while the flange 402 is installed.

FIG. 6E shows the flange nut 404 installed into the flange 402. The threaded segment 426 of the flange nut 404 is engaged with the threaded inner surface 412 of the flange 402. The ring 432 of the flange nut 404 is in contact with the land 324 of the port nut 202, pressing against the port nut 202 and restricting the ability of the port nut 202 to back out of the port 210. The bottom surface 318 does not contact with the external surface 208, such that the flange nut 404 only presses against the port nut 202. The top surface 320 of the port nut 202 is generally nested within the cavity 430 of the flange nut 404, however the top surface 320 does not contact the cavity 430 flange at 404.

Although described above as installed in a specific manner, the components may generally be installed in many different orders. For example, the flange 402 may be installed at any stage as it does not interfere with the installation of the plug 308 or port nut 202, and the flange nut 404 may be preinstalled within the flange 402. Further, the retaining kit 400 may be installed on a pump block 200 without removing the port nut 202 and/or plug 308, such that it may simply be added to the existing setup.

Further, although the various components above are described as located in specific positions while installed, there may be a variety of acceptable installation positions for the components. In one example, the mounting face 406 of the flange 402 may be partially engaged with the external face 208 when installed on the pump block 200. In another example, the land 324 of the port nut 202 may be outside of or within the port 210 when the port nut 202 is threaded into the port 210. In a third example, the flange 402 may engage the port nut 202 when in the installed position. Additionally, the port nut 202 and/or flange nut 404 may have differently shaped and/or sized tool apertures 326, tool holes 424, and/or tool bores 428, or may lack them entirely.

FIG. 7 shows an exterior view of a hydraulic pump 106. As shown, each of the 5 ports 210 are shown at a different step of the installation process, as shown and described in FIGS. 6A-6E. From left-to-right, the first port 210 is completely open to the pumping chamber 212, generally corresponding with what is shown in FIG. 6A. The second port 210 has the plug 308 installed, generally corresponding with what is shown in FIG. 6B. The third port 210 has the port nut 202 installed, generally corresponding with what is shown in FIG. 6C. The fourth port 210 has the flange 402 installed, generally corresponding with what is shown in FIG. 6D. Finally, the fifth port 210 has the flange nut 404 installed, generally corresponding with what is shown in FIG. 6E.

INDUSTRIAL APPLICABILITY

The retaining kit 400 may be used for securing a port nut 202 within a pump block 200. The retaining kit 400 includes a flange 402 and a flange nut 404. The flange 402 mates with the external surface 208 of the pump block 200. The flange nut 404 mates with the flange 402 and engages the port nut 202 when the port nut 202 is installed within the port 210 of the pump block 200. The differing pitches of the threaded radial surface 316 and threaded segment 426 effectively lock the port nut 202 to the flange nut 404 without the use of fasteners, such that rotation of the port nut 202 does not also rotate the flange nut 404.

Accordingly, the pump block 200 using the retaining kit 400 may have port nuts 202 that better resist the disruptive forces of high pressures and vibrations of the pump block 200. As such, the port nuts 202 may experience less loosening within the ports 210. Thereby, the ports 210 may be less susceptible to fluid leakage and damage, and therefore may require less monitoring, maintenance, and repair.

While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems, and methods without departing from the spirit and scope of the disclosure. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.