Liner lock flange for a piston pump

A piston pump includes a frame, a housing configured to be coupled to the frame via a fastener, an annular liner defining a chamber configured to receive a piston of the piston pump, and an annular liner lock flange circumferentially surrounding the annular liner. The annular liner lock flange includes a radially-extending portion configured to be positioned within a respective counterbore of the frame and a respective counterbore of the housing while the housing is coupled to the frame via the fastener to block relative movement between the liner lock flange, the frame, and the housing.

BACKGROUND

Natural resources, such as oil and gas, are used as fuel to power vehicles, heat homes, and generate electricity, in addition to various other uses. Once a desired resource is discovered below the surface of the earth, drilling and production systems are often employed to access and extract the resource. These systems may be located onshore or offshore depending on the location of the desired resource. Further, such systems may include a wide variety of components, such as various casings, fluid conduits, valves, pumps, and the like, that facilitate extraction of the resource from a well during drilling or extraction operations. For example, a mud pump system may be utilized to pump drilling fluid (e.g., mud) from surface tanks into a drill pipe. However, some mud pump systems may be difficult to maintain and/or repair, thereby resulting in increased downtime during maintenance and/or repair operations.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

The present embodiments are generally directed to pump systems for use within a drilling and production system. Certain embodiments include a pump system having a liner lock flange (e.g., annular flange) designed to facilitate alignment between a piston liner (e.g., annular liner) and a piston, and to also enable replacement of a wear plate (e.g., annular plate) without removal of the liner lock flange. The disclosed embodiments may advantageously provide a compact pump system, may reduce wear on components of the pump system, and/or may facilitate maintenance and/or repair of the components of the pump system, for example. It should be appreciated that the liner lock flange that is used as part of the pump system disclosed herein may be adapted for use with various types of equipment, such as any piston pump system, including but not limited to mud pump systems.

With the foregoing in mind,FIG. 1is a schematic diagram of a portion of a drilling and production system10, in accordance with an embodiment of the present disclosure. As shown, a wellbore12is formed in a subsurface formation, and a drill string14is suspended within the wellbore12. The drill string may include a drill bit16that cuts through the subsurface formation to form or to drill the wellbore12. The system10includes a mast18positioned on a drill floor20and over the wellbore12. A hoisting system22includes a crown block24, a traveling block26, and a drawworks system28. A cable30(e.g., wire) extends from the drawworks system28and couples the crown block24to the traveling block26. In the illustrated embodiment, a top drive32is coupled to the traveling block26. The top drive32rotates the drill string14as the hoisting system22raises and lowers the top drive32and the drill string14relative to the drill floor20to facilitate drilling of the wellbore12. It should be appreciated that hoisting systems having various other components (e.g., swivels) and configurations may be utilized in the system10.

The system10also includes a pump system40having a pump42that pumps a drilling fluid (e.g., mud; water-based, oil-based, or synthetic-based fluid) from a tank44to an interior channel in the drill string14. For example, the pump42may pump the drilling fluid from the tank44, through a fluid conduit46(e.g., pipe), through a port in the top drive32, and into the interior channel in the drill string14, as shown by arrow48. The drilling fluid may exit the drill string14via ports in the drill bit16, and then circulate upwardly through an annulus between an outer surface (e.g., annular surface) of the drill string14and an inner surface (e.g., annular surface) that defines the wellbore12, as shown by arrows50. The drilling fluid may then return to the tank44via a fluid conduit52(e.g., pipe). The drilling fluid may lubricate the drill bit16, may carry formation cuttings toward the surface, and/or may maintain hydrostatic pressure within the wellbore12. As discussed in more detail below, the pump42may include a liner assembly54(e.g., piston liner assembly) with various features that facilitate operation of the pump42, as well as maintenance of the pump42, for example. WhileFIG. 1illustrates a land-based drilling and production system10to facilitate discussion, it should be understood that the disclosed embodiments may be adapted for use within an offshore drilling and production system.

FIG. 2is a cross-sectional side view of the pump42that may be used in the drilling and production system10ofFIG. 1. To facilitate discussion, the pump system42and its components may be described with reference to an axial axis or direction56, a radial axis or direction58, a lateral axis or direction60, and a circumferential axis or direction62.

In the illustrated embodiment, the pump42is supported on a skid64(e.g., support structure) and includes a frame68(e.g., main frame) that is coupled to the skid64. The pump42extends from a power end portion70to a fluid end portion72. The power end portion70may include components of a drive system74(e.g., motor, gears, and/or crankshaft assembly that coverts rotation into reciprocating motion to drive one or more pistons76back and forth along the axial axis56). The fluid end portion72may include the one or more pistons76, one or more modules78(e.g., housings) surrounding and/or supporting one or more valves80(e.g., one-way check valves), and one or more fluid inlets82(e.g., suction manifold) through which the drilling fluid is drawn (e.g., suctioned) into the one or more modules78to be pumped (e.g., discharged) toward the drill string14(FIG. 1). The frame68surrounds (e.g., houses or covers) the one or more pistons76and associated components (e.g., piston rod), and the frame68is coupled to the one or more modules78. As shown in the illustrated embodiment, each piston76is associated with a suction module84and a discharge module86that are coupled to one another. In operation, the reciprocating motion of the piston76draws the drilling fluid, for example mud, in through a corresponding fluid inlet82and a corresponding suction module84and then forces the mud out through a corresponding fluid outlet or discharge manifold extending from a corresponding discharge module86(e.g., positioned out of view behind the discharge module84along the lateral axis60inFIG. 2).

In the illustrated embodiment, the fluid end portion72also includes one or more liner assemblies54, and each of the one or more liner assemblies54circumferentially surrounds a respective one of the one or more pistons76. One liner assembly54is shown schematically inFIG. 2to illustrate its position relative to other components of the pump42, and details of the liner assembly54are shown inFIGS. 3 and 4. In general, the liner assembly54may include a liner defining a chamber through which the piston76moves, as well as a liner lock flange and associated liner lock nut that together retain the liner in its position proximate to a respective one of the one or more modules78.

In the cross-section ofFIG. 2, only one piston76and its corresponding modules78and corresponding liner assembly54are shown. However, it should be appreciated that the pump42may include multiple pistons76and corresponding modules78and liner assemblies54distributed along the lateral axis60(e.g., side-by-side along the lateral axis60). Furthermore, while each piston76has two corresponding modules78(e.g., the suction module84and the discharge module86) inFIG. 2, it should be appreciated that each piston76may have only one corresponding module78having a different valve structure to enable suction and discharge functionality.

FIG. 3is a side view of the liner assembly54that may be used in the pump42(FIG. 2), andFIG. 4is a side view of the liner assembly54taken within line4-4ofFIG. 3, in accordance with an embodiment of the present disclosure. InFIG. 3, only a portion of the frame68is shown to facilitate discussion and to simplify the drawing. Furthermore, the illustrated module78includes a different valve structure than the modules78shown inFIG. 2, but the valves80operate in the same manner to suction and discharge the drilling fluid.

As shown inFIGS. 3 and 4, the frame68is coupled to the module78via one or more fasteners100(e.g., threaded fasteners, such as bolts, studs, nuts). The liner assembly54includes a liner102(e.g., annular liner) defining a chamber through which the piston76(FIG. 2) moves. The liner assembly54also includes a liner lock flange104(e.g., annular flange) and a liner lock nut106(e.g., annular nut) that together retain the liner102in its position proximate to the module78. In the illustrated embodiment, the liner lock flange104and the liner lock nut106are coupled to one another via a threaded interface108, although other coupling interfaces (e.g., key-slot interface, j-slot, quarter-turn) may be utilized.

The liner assembly54may include a wear plate110(e.g., annular wear plate or sleeve), a wear plate seal112(e.g., annular seal), and/or a liner seal114(e.g., annular seal). As shown, the wear plate110is positioned between the module78and the liner102along the axial axis56. In some embodiments, this may be a high-wear region due at least in part to a difference between an inner diameter116of the liner102and an inner diameter118of a bore120of the module78(e.g., the inner diameter116is greater than the inner diameter118). The wear plate seal112seals against and is positioned between the wear plate110and the module78along the axial axis56. The liner seal114seals against and is positioned between the wear plate110and the liner102along the axial axis56. When assembled, the liner lock flange104may circumferentially surround at least a portion of the wear plate110.

The liner assembly54is designed to facilitate alignment between the liner102and the piston76(FIG. 1), and also to enable replacement of the wear plate110(as well as the liner seals114,116) without removal of the liner lock flange104. As shown, the liner lock flange104extends from a first end122that couples to the liner lock nut106to a second end124that includes a radially-extending flange126(e.g., annular flange or portion). A portion of the radially-extending flange126is positioned within a counterbore128(e.g., annular recess) formed in a module-facing surface130(e.g., housing-facing or axially-facing surface) of the frame68. Another portion of the radially-extending flange126is positioned within a counterbore132(e.g., annular recess) formed in a frame-facing surface134(e.g., axially-facing surface) of the module78. When the frame68is coupled to the module78via the fasteners100, the radially-extending flange126within the counterbores128,132is trapped between the frame68and the module78, thereby blocking movement of the liner lock flange104relative to the frame68and the module78. It should be appreciated that the liner lock nut106may be rotated to drive the liner102toward the liner lock flange104, thereby tightening the fit or connection between the various components (e.g., between the liner102, the liner lock flange104, the module78).

To assemble the liner lock flange104within the pump42(FIG. 1), the liner lock flange104may be inserted into an opening (e.g., bore) defined by the frame68from a module-facing side (e.g., housing-facing side) of the frame68, as shown by arrow140. The liner lock flange104and the frame68may be moved toward one another along the axial axis56until a frame-engaging surface142(e.g., axially-facing surface) of the radially-extending flange126engages a flange-engaging surface144of the frame68. The frame68may then be coupled to the module78via the threaded fasteners100, and the position of the radially-extending flange126in both counterbores128,132assists in alignment between the frame68and the module78.

The other components of the liner assembly54may then be assembled. In particular, the components may be inserted through the liner lock flange104from a piston-facing side of the frame68(e.g., opposite from the module-facing side of the frame68), as shown by arrow148. For example, the wear plate seal112may be inserted and positioned within the module78, then the wear plate110may be inserted and positioned against the module78, then the liner seal114may be inserted and positioned into a groove within the liner102, then the liner102may be inserted and positioned against the wear plate110. Subsequently, the liner lock nut106may be coupled to (e.g., threaded onto) the liner lock flange104. As shown, the liner102includes a radially-extending liner flange150(e.g., annular flange). When the liner lock nut106is coupled to the liner lock flange104, the radially-extending liner flange150is positioned between the liner lock nut106and the liner lock flange104along the axial axis56. In particular, an axially-facing surface152of the liner lock nut106and an axially-facing surface154at the first end122of the liner lock flange104each engage the radially-extending liner flange150and block movement of the liner102relative to the liner lock nut106and the liner lock flange104. It should be appreciated that the liner102may not include the liner flange105, but instead the liner lock nut106may extend to and engage an end of the liner102to block movement of the liner102relative to the liner lock nut106and the liner lock flange104. To replace the liner lock flange104, the fasteners100are loosened to separate the module78from the frame68, and then the liner lock flange104can be moved out of the frame68(e.g., by pulling the liner lock flange in a direction opposite arrow140). Another liner lock flange104, and the other components of the liner assembly54, can then be assembled in the manner set forth above.

In operation, the piston76(FIG. 2) moves through the liner102along the axial axis56to pump the drilling fluid through the module78. The disclosed embodiments enable the liner102to remain in its position tightly against the wear plate110, and enables the wear plate110to remain in its position tightly against the module78during operation of the pump42(FIG. 2) without any fasteners (e.g., threaded fasteners, such as bolts) coupling the liner lock flange104to the module78and without any fasteners (e.g., threaded fasteners, such as bolts) coupling the liner lock flange104to the frame68. Thus, the liner lock flange104may be devoid of openings to receive fasteners. The lack of such fasteners provides a small, light-weight pump42(FIG. 2) with fewer parts compared to some existing drilling fluid pumps such as mud pumps or slurry pumps.

Furthermore, the disclosed embodiments enable replacement of the liner102, the wear plate110, the wear seal112, and/or the liner seal114without removing the liner lock flange104(e.g., without separating the liner lock flange104from the frame68and/or the module78). The liner102, the wear plate110, the wear seal112, and/or the liner seal114are subject to wear and may need to be replaced relatively frequently (e.g., compared to the liner lock flange104), and this configuration enables efficient replacement of these high-wear components without removing the liner lock flange104or altering alignment between the frame68and the module78(e.g., since the liner lock flange104, the frame68, and the module78are not separated from one other during replacement of the liner102, the wear plate110, the wear seal112, and/or the liner seal114). For example, the liner102, the wear plate110, the wear seal112, and/or the liner seal114can be removed by uncoupling the liner lock nut106from the liner lock flange104, and subsequently pulling the liner102, the wear plate110, the wear seal112, and/or the liner seal114through the liner lock flange104in a direction opposite the arrow148. As shown, the liner lock flange104includes an inner diameter160that is greater than an outer diameter162of the wear plate110, and the inner diameter160also accommodates removal of the seals112,114and the liner102.

The disclosed embodiments enable a tight fit (e.g., press fit) between the liner lock flange104and the frame68and/or between the liner lock flange104and the module78because the liner lock flange104does not need to be separated from the frame68and/or the module78during regular maintenance operations to replace the liner102, the wear plate110, the wear seal112, and/or the liner seal114. In contrast, some existing liner lock flanges108must be removed or separated from the frame68and/or the module78(e.g., by uncoupling threaded fasteners that hold the liner lock flange104to the frame68and/or to the module78) to replace the liner102, the wear plate110, the wear seal112, and/or the liner seal114, and as a result, the parts may generally have relatively loose fits to assist with loosening the fasteners and the like. The tight fit in the present embodiments maintains alignment between the liner102and the piston76(FIG. 2), thereby reducing wear on the liner102and the piston76(FIG. 2) and extending component life.

FIG. 5is a method200of assembling a portion of the pump42(FIG. 2). The method200includes various steps represented by blocks. Although the flow chart illustrates the steps in a certain sequence, it should be understood that the steps may be performed in any suitable order and certain steps may be carried out simultaneously, where appropriate. Additionally, steps may be added to or omitted from of the method200. The discussion of the method200refers to certain components that are described and illustrated inFIGS. 1-4.

In step202, the radially-expanded portion126of the liner lock flange104is positioned within the counterbore128of the frame68. As discussed above, the liner lock flange104may be inserted into an opening defined by the frame68from the module-facing side of the frame68, as shown by arrow140. The liner lock flange104and the frame68may be moved toward one another along the axial axis56until the frame-engaging surface142of the radially-extending flange126engages the flange-engaging surface144of the frame68.

In step204, the radially-extending portion126of the liner lock flange104is aligned with and positioned within the counterbore132of the module78. In step206, the frame68may then be coupled to the module78(e.g., via the threaded fasteners100). The position of the radially-extending flange126in both counterbores128,132assists in alignment between the frame68and the module78.

In step208, once the liner lock flange104is secured to the frame68and the module78, the wear plate110may be inserted through the liner lock flange104to a position against the module78. In step210, the liner102may be inserted through the liner lock flange104to a position against the wear plate110. In step212, the liner lock nut106may then be coupled to the liner lock flange104to secure the liner102and block movement of the liner102relative to the liner lock flange104and relative to the liner lock nut106. As noted above, the liner102, the wear plate110, the wear seal112, and/or the liner seal114may be removed through the liner lock flange104without separating the liner lock flange104from the frame68or the module78.

The pump42disclosed herein is merely exemplary, and it should be appreciated that various combinations and arrangements of the features shown and described with respect toFIGS. 1-4are envisioned. Indeed, any of the features and components ofFIGS. 1-5may be utilized together and/or combined in any suitable manner. Furthermore, the liner assembly54and some or all of the components therein may be used in any of a variety of piston pump systems.