Patent ID: 12247557

Like reference numerals have been used to identify like elements throughout this disclosure.

DETAILED DESCRIPTION

The following description is not to be taken in a limiting sense but is given solely for the purpose of describing the broad principles of the invention. Embodiments of the invention will be described by way of example, with reference to the above-mentioned drawings showing elements and results according to the present invention.

Generally, the sealing assembly presented herein provides a bore seal with an extended lifespan, at least as compared to conventional (e.g., stationary) bore seals. The sealing assembly provides an extended lifespan because a seal element included in the sealing assembly can be selectively/progressively axially repositioned to seal against unworn surfaces. For example, over time, the seal element/seal ring can move/migrate axially upstream with respect to the remainder of the sealing assembly, sealing against surfaces that were previously unexposed to fluid for which the seal ring is providing a seal and/or previously unexposed to wear associated with providing such a seal. As is detailed below, the seal ring is included in or coupled to a seal element that is installable between a fluid end casing and a closure element. Then, the seal element may be moved axially by reconfiguring the seal element and/or by selectively replacing the seal element.

Notably, since the sealing is achieved between a closure element and the fluid end casing (either directly or indirectly, e.g., via a sleeve disposed between the seal element and the casing), a closure element that supports the sealing assembly (e.g., a plug, cover, and/or sleeve) need not be extensively machined to form multiple grooves. This may save cost and/or time during manufacturing. Moreover, when a closure element includes multiple grooves, the grooves have to be adequately spaced to ensure that each groove is supported by enough material to avoid failure. That is, if a closure element includes multiple grooves, the grooves must be axially spaced along the closure element so that fin-like structures extending between the grooves are strong enough to support a seal against forces generated by high pressures acting on the seal.

Still further, with the techniques presented, the same closure element (e.g., plug, cover, sleeve, or even plunger) can be re-used while one or more sealing positions defined on the closure element and/or the fluid end are moved. By comparison, some solutions achieve different sealing positions with different closure elements, which wastes material and creates cost and inventory disadvantages for the end user, who must buy, track and maintain multiple closure elements. In fact, in at least some embodiments presented herein, the sealing assembly can provide multiple sealing assemblies for preexisting closure elements and/or fluid ends (e.g., preexisting casings and preexisting suction and/or discharge plugs). That is, at least some embodiments presented herein provide a solution that can be retrofit onto existing pumping/drilling components.

Now referring toFIG.1for a description of an exemplary embodiment of a reciprocating pump100in which the sealing assembly presented herein may be included. The reciprocating pump100includes a power end102and a fluid end104. The power end102includes a crankshaft that drives a plurality of reciprocating plungers within the fluid end104to pump fluid at high pressure. Generally, the power end102is capable of generating forces sufficient to cause the fluid end104to deliver high pressure fluids to earth drilling operations. For example, the power end102may be configured to support hydraulic fracturing (i.e., fracking) operations, where fracking liquid (e.g., a mixture of water and sand) is injected into rock formations at high pressures to allow natural oil and gas to be extracted from the rock formations. However, to be clear, this example is not intended to be limiting and the present application may be applicable to both fracking and drilling operations.

Often, the reciprocating pump100may be quite large and may, for example, be supported by a semi-tractor truck (“semi”) that can move the reciprocating pump100to and from a well. Specifically, in some instances, a semi may move the reciprocating pump100off a well when the reciprocating pump100requires maintenance. However, a reciprocating pump100is typically moved off a well only when a replacement pump (and an associated semi) is available to move into place at the well, which may be rare. Thus, often, the reciprocating pump is taken offline at a well and maintenance is performed while the reciprocating pump100remains on the well. If not for this maintenance, the reciprocating pump100could operate continuously to extract natural oil and gas (or conduct any other operation). Consequently, any improvements that extend the lifespan of components of the reciprocating pump100, especially typical “wear” components, and extend the time between maintenance operations (i.e., between downtime) are highly desirable.

FIG.2is a sectional view taken along line D-D ofFIG.1, which is representative of a central or plunger axis of one of the plungers202(seeFIG.1) included in reciprocating pump100. InFIG.2, the plunger202is omitted; however, generally, the fluid end104forms a plurality of pumping chambers208and each chamber208includes a plunger that reciprocates within a casing206of the fluid end104. With each stroke of the plunger202, low pressure fluid is drawn into the pumping chamber208and high pressure fluid is discharged. Often, the fluid within the pumping chamber208contains abrasive material (i.e., “debris”) that can damage seals formed in the reciprocating pump100.

The pumping paths and pumping chamber208of the fluid end104are formed by conduits that extend through the casing206to define openings at an external surface210of the casing206. More specifically, a first conduit212extends longitudinally (e.g., vertically) through the casing206while a second conduit222extends laterally (e.g., horizontally) through the casing206. Thus, conduit212intersects conduit222to at least partially define the pumping chamber208. As is illustrated, the diameters of conduit212and conduit222may vary throughout the casing206so that the conduits can receive various structures, such as sealing assemblies or components thereof.

Regardless of the diameters of conduit212and conduit222, each conduit may include two segments, each of which extend from the pumping chamber208to the external surface210. Specifically, conduit212includes a first segment2124and a second segment2126that opposes the first segment2124. Likewise, conduit222includes a third segment2224and a fourth segment2226that opposes the third segment2224. In the depicted embodiment, the segments of a conduit (e.g., segments2124and2126or segments2224and2226) are substantially coaxial while the segments of different conduits are substantially orthogonal. However, in other embodiments, segments2124,2126,2224, and2226may be arranged along any desired angle or angles, for example, to intersect pumping chamber208at one or more non-straight angles.

Still referring toFIG.2, in the depicted embodiment, conduit212defines a fluid path through the fluid end104. Segment2126is an intake segment that connects the pumping chamber to piping delivering fluid to the fluid end104. Meanwhile, segment2124is an outlet segment that allows compressed fluid to exit the fluid end104. Thus, in operation, segments2126and2124may include valve components (e.g., one-way valves) that allow segments2126and2124to selectively open. However, typically, valve components in the inlet segment2126may be secured therein by piping while valve components in outlet segment2124may be secured therein by a sealing assembly that, for example, is secured to and seals against an interior wall of casing206defining segment2124.

On the other hand, conduit222defines, at least in part, a cylinder for plunger202, and/or connects the casing206to a cylinder for plunger202. Thus, reciprocation of a plunger in or adjacent to segment2226draws fluid into the fluid chamber208via inlet segment2126and pumps the fluid out of the fluid chamber208via outlet segment2124. Segment2224is an access segment that provides access to parts and surfaces disposed or defined within casing206. However, in some embodiments, conduit222need not include segment2224and conduit222may be formed from a single segment (segment2226) that extends from the pumping chamber208to the external surface210.

Still referring toFIG.2, but now in combination withFIG.1, althoughFIG.2depicts a single pumping chamber208, it should be understood that a fluid end104can include multiple pumping chambers208arranged side-by-side. In some embodiments, the fluid end104may be modular and different casing segments may house one or more pumping chambers208. Additionally or alternatively, multiple pumping chambers208may be formed in a single casing segment or casing. Regardless of how the casing206is formed, the one or more pumping chambers208included therein are arranged side-by-side so that corresponding conduits are positioned adjacent each other and generate substantially parallel pumping action.

In operation, fluid may enter fluid end104via multiple openings, as represented by opening216inFIG.2, and exit fluid end104via multiple openings, as represented by opening214inFIG.2. In at least some embodiments, fluid enters openings216via pipes of a piping system106(seeFIG.1), flows through pumping chamber208(due to reciprocation of a plunger202), and then flows through openings214into a channel108(seeFIG.1). However, piping system106and channel108are merely example conduits and, in various embodiments, fluid end104may receive and discharge fluid via any number of pipes and/or conduits, along pathways of any desirable size or shape.

During operations of pump100, the first segment2124(of conduit212), the third segment2224(of conduit222), and the fourth segment2226(of conduit222) may each be “closed” segments. By comparison, the second segment2126(of conduit212) may be an “open” segment that allows fluid to flow from the external surface210to the pumping chamber208. That is, for the purposes of this application, a “closed” segment may prevent, or at least substantially prevent, direct fluid flow between the pumping chamber208and the external surface210of the casing206while an “open” segment may allow fluid flow between the pumping chamber208and the external surface210. To be clear, “direct fluid flow” requires flow along only the segment so that, for example, fluid flowing from pumping chamber208to the external surface210along segment2124and channel108does not flow directly to the external surface210via segment2124.

In operation, segment2124, segment2224, and segment2226may be each be completely capped, sealed, plugged, or otherwise closed to prevent fluid from passing through one of these segments to the external surface210of casing206. In segment2124or segment2224, this seal may be achieved with a plug-style or plug-type version of sealing assembly300. For simplicity, the Figures (e.g.,FIGS.8A-8C and9-13) only show a plug-style sealing assembly positioned in segment2224, but segment2124may also receive any plug-style embodiment of sealing assembly300. In fact, in some instances, a sealing assembly300disposed in segment2124may be referred to as a discharge plug and a sealing assembly300disposed in segment2224may be referred to as a suction plug.

On the other hand, a sleeve-style/type version of sealing assembly300(i.e., a modified version of sealing assembly300) may be used to seal segment2226. A sleeve-style sealing assembly300may be an annular version of sealing assembly300. For example, although not shown herein, a sleeve-style sealing assembly300may extend between casing206and a packing arrangement. Thus, in some instances, a sealing assembly300disposed in segment2226may be referred to as a packing sleeve. For the purposes of this application, a sleeve- or plug-style closer element may be referred to as a stationary closure element. However, the techniques presented herein need not be limited to stationary closure elements and may also be used in combination with plungers or other movable closure elements, which, for the purposes of this application, may be referred to as movable closure elements.

More specifically, the concepts presented herein (e.g., in connection with sealing assembly300) may be applied to a packing arrangement and a movable closure element. That is, the sleeve-style sealing assembly300presented herein may embodied as a packing arrangement and plunger. In such instances, the annular seal element of the sealing assembly presented herein may be a packing disposed between a casing206and a plunger202. Then, the plunger202and the annular seal element (e.g., the packing) may form the sealing assembly presented herein. To be clear, for the purposes of this application, a sealing assembly formed from a packing arrangement and plunger may be referred to as a sealing assembly for a movable closure element. By comparison, sealing assemblies embodied as plug-style or sleeve-style closure elements (with seal elements disposed around a stationary closure element) may be referred to as sealing assemblies for stationary closure elements.

Still referring toFIG.2, during setup/servicing of the fluid end104, sealing assemblies300may be inserted into segment2124, segment2224, and/or segment2226. Then, retaining elements (e.g., retaining element500ofFIG.8Aor retaining element800ofFIG.13, each of which may also be referred to as lock members, retaining nuts, etc.) may be installed exteriorly of each sealing assembly300to secure the sealing assembly300therein. In the embodiment depicted inFIG.2, segment2124, segment2224, and segment2226include threads2128, threads2228, and threads2229, respectively, disposed adjacent the external surface210of the casing206. Thus, a retaining element500/800may be threaded into place to secure a sealing assembly300into segment2124, segment2224, or segment2226.

However, in other embodiments, sealing assemblies300may be secured in segment2124, segment2224, and/or segment2226via any desired techniques, e.g., with fasteners, pressure, and/or additional closure components, either in addition to or in lieu of threaded retaining elements, provided that the techniques allow the sealing assemblies300to be removed for reconfiguration or replacement, pursuant to the techniques detailed below. Moreover, sealing assemblies300may be installed in segment2124, segment2224, and segment2226with the same or different techniques, structures, etc.; but, the sealing assemblies300should each be removable from their segment to allow for servicing of the sealing assemblies300and/or to allow for servicing of components/parts sealed inside the casing206by the sealing assembly300(e.g., one-way valves, the casing itself, etc.). As an example, in some embodiments, the sealing assemblies300may be threaded into engagement with threads on the casing206, either in addition to or in lieu of threaded retaining elements.

Now turning toFIG.3, the sealing assembly300presented herein includes a closure element302and a seal element320(which may also referred to as a seal subassembly320). In the embodiments depicted in at leastFIGS.3,4A,4B,8A-8C, and9-13, the closure element302is illustrated as a plug; however, as mentioned, closure element302may be in the form of a plug/cover, a sleeve, or even a plunger (with the seal element being in the form of a packing arrangement). Regardless, the closure element302has a substantially circular, or at least ovular, cross-sectional outer shape that is configured to substantially mate with a segment for which it is intended (e.g., segment2124, segment2224, or segment2226). Additionally, in the depicted embodiments, the exterior of the closure element302has multiple steps/diameters defined by a flange304and a sealing portion310(seeFIG.4A).

Specifically, and now turning toFIG.4A, the flange304extends from a top or proximal surface306to a bottom or distal surface308while overhanging the sealing portion310. Thus, when the sealing assembly300is inserted into a segment (e.g., segment2124, segment2224, or segment2226), the flange304may sit on a seat defined in or at the end of the segment, limiting axial displacement of the sealing assembly within a segment. In some embodiments, sealing assemblies may be specifically designed for specific segments, for example, by dimensioning flange304to engage a seat with a specific diameter/specific dimensions.

In some embodiments, the proximal surface306of the flange304includes a cavity307(see, e.g.,FIG.8A) that may facilitate installation and/or create resilience for sealing. Additionally, in the depicted embodiments, an external radial surface (i.e., a side, outer surface) of flange304may be sloped or angled towards a radially extending lip309(shown best inFIGS.8A-8C) to encourage sealing and/or engagement with a retaining element (e.g., retaining element500). However, in various embodiments, the flange304may include any other features, in combination with one, none, or both of the cavity307and lip309for any desirable reason (e.g., sealing, installation, engagement with a retaining element, etc.).

Still referring toFIG.4A, the sealing portion310is generally configured to receive the seal element320and to form one or more seals against a casing segment within which the sealing assembly300is installed (e.g., segment2124, segment2224, or segment2226). However, before discussing these features, it is important to understand the terms “upstream” and “downstream.” Any fluid flow through casing206flows through pumping chamber208and may contact a bottom or distal end of a sealing assembly300that forms a seal that closes a segment (e.g., to prevent flow between the pumping chamber208and the external surface210of the casing206). Thus, if a first component (e.g., a surface or portion) is described as being “upstream” of a second component (e.g., another surface or portion) the first component will be closer to the fluid flow (and high pressures associated therewith) than the second component (i.e., closer to pumping chamber208). On the other hand, if a first component is described as being “downstream” of a second component, the first component will be closer to the external surface210of the casing206(and the relatively low pressures associated therewith) than the second component.

Now, as can be seen inFIG.4A, the sealing portion310extends from the distal surface308of the flange304. In the depicted embodiments, the sealing portion310is substantially cylindrical, insofar as the term “substantially” indicates that edges of the cylinder (e.g., edges between a sidewall and a top/bottom) may be rounded, chamfered, or otherwise non-right angled. However, the sealing portion310need not be substantially cylindrical. In any case, the sealing portion310includes at least one lateral surface314on which the seal element320may be installed. In the embodiment depicted inFIG.4A, the lateral surface terminates at a notch316that is spaced from a distal end of the sealing portion310. That is, the lateral surface314for the seal element320extends over a portion of the sealing portion310. Then, a secondary lateral surface318extends from the notch316to a distal surface312of the sealing portion310(which defines a distal end of the closure element302).

In the depicted embodiment, the notch316is included in the sealing portion310so that the closure element302can receive and support a retaining ring330(seeFIG.3) that retains the seal element320on the lateral surface314. The retaining ring330may be a snap ring that locks onto the notch316, but this is just an example of a retaining feature and any other features, such as pins and/or threads could be used in combination with or in lieu of a retaining ring330secured onto notch316to axially secure a seal element320on the lateral surface314of the sealing portion310. In any case, retaining an upstream end of the seal element320may be advantageous because it may allow the seal element320to be installed in a gap between the closure element302and casing206without modifying the casing206and/or the closure element302(especially if a retaining feature, such as retaining ring330, can be secured to the closure element302without a notch316or other such mating feature).

Now turning toFIG.4B, in at least some embodiments, the lateral surface of the sealing portion310(e.g., the surface on which the seal element320may be installed) extends to and terminates at or adjacent the distal surface312of the closure element302. Thus,FIG.4Bdepicts another embodiment of a closure element302′ that is similar to closure element302, except for its sealing portion310′. More specifically, closure element302′ has a flange304that is similar to (if not identical to) the flange of closure element302, but the sealing portion310′ of closure element302′ does not include a notch316or a secondary lateral surface318. Instead, the sealing portion310′ includes a lateral surface314′ that extends from the bottom or distal surface308of the flange304to the distal surface312of the closure element302. That said, due the similarities between closure element302and closure element302′, any description of like parts should be understood to apply to both embodiments unless otherwise explicitly stated.

To be clear, closure element302and closure element302′ are merely two examples of closure elements that may included in the sealing assembly300presented herein and other embodiments may include other variations. For example, a closure element suitable for the techniques presented herein may include a secondary lateral surface318that is shorter or longer than the secondary lateral surface318depicted inFIG.4A(and it may be shorter or longer than lateral surface314) and/or may include other features (e.g., in addition to or in lieu of notch316). Still further, as mentioned, in at least some embodiments closure element302may be configured as a sleeve or plunger (an example of which is discussed below).

Now turning back toFIG.3, in some embodiments, the seal element320may have some elasticity and/or resiliency so that the seal element320can be slid over the distal surface312of the sealing portion310and onto the lateral surface314(for simplicity, seal elements320are generally described herein with respect to lateral surface314, but this is merely representative of any lateral surface included on a closure element, such as lateral surface314′). Then, this elasticity and/or resiliency may bias the seal element320inwards against the lateral surface314once the seal element320is disposed around the lateral surface314. That is, a resiliency or elasticity of the seal element320may create inwards pressure that removably couples the seal element320to the lateral surface314of the closure element302. Additionally or alternatively, the seal element320may be skive cut to facilitate sliding/stretching. In any of these instances, when a seal created by the seal element320begins to fail, the seal element320may be slid over the distal surface312of the sealing portion310to remove and replace or reconfigure the seal element320.

However, in other embodiments, the seal element320need not be resiliently biased against the lateral surface314and could, for example, sit between the closure element302and the casing206. In some of these embodiments, the seal element320may be axially secured between the flange304and a retaining ring330without creating pressure against the lateral surface314. Additionally or alternatively, the seal element320may be axially secured between the flange304and a portion of casing206without creating pressure against the lateral surface314. Then, during operations, the retaining ring330and/or casing206may prevent axial movement of the seal element320in an upstream direction and, may, for example, convert upstream axial movement into radial compression against casing206and/or the closure element302. Likewise, the flange304and/or casing206might prevent axial movement of the seal element320in a downstream direction and, may, for example, convert downstream axial movement into radial compression against casing206and/or the closure element302.

In fact, in some embodiments, sliding an unbiased seal element320over the closure element302and/or into the casing206may prove advantageous since it will remove the need for stretching and/or cutting (which is typically required when a seal element320slips into a groove formed in the closure element). When this stretching and cutting is eliminated, the seal element320can be formed from harder materials (e.g., minimally stretchable) and/or can be a continuous, uncut element. For example, the seal element320, or at least portions thereof, may have a hardness of at least Shore 60D. Additionally or alternatively, the seal element320, or at least portions thereof, could be made of different materials when the seal element320need not be stretched or cut (e.g., in addition to or instead of pure rubber), such as fiber-filled or fabric-reinforced constructions. However, to be clear, retaining ring330and/or the casing206can also retain a seal element320that is biased against the lateral surface314by its resiliency/elasticity. Additionally or alternatively, insertion of the sealing assembly300into a segment of the casing206(e.g., segment2124, segment2224, or segment2226) may generate compressive forces that removably couple the seal element320to the closure element302.

Still further, in some embodiments, the seal element320may be irremovably coupled (e.g., integrally formed with or bonded to) to the closure element302. Thus, the sealing assembly300may be a unitary or monolithic component. However, in such embodiments, when a seal formed by the seal element320begins to leak/fail, the entire sealing assembly300might need to be replaced.

Now turning toFIGS.5,6,7A, and7B, these figures depict three embodiments of seal elements—seal element320, seal element320′, and seal element320″—that can be included in a sealing assembly300presented herein. However, the depicted embodiments are merely examples and are not intended to be limiting in any way. For example, even though certain figures include a certain number of seals, this does not mean that embodiments with a specific number seals must be formed/constructed in a specific manner. Instead, for brevity,FIGS.5,6,7A, and7Billustrate various seal element embodiments and various features, elements, concepts, and/or principles of one embodiment may be combined with various features, elements, concepts, and/or principles of any other embodiment in any manner.

As some specific examples, the embodiments ofFIG.5and/or the embodiment of7A and7B could be formed with multiple seals and/or the embodiment ofFIG.6could include a single seal. Additionally or alternatively, a portion of theFIG.5embodiment could be combined with a portion of theFIG.6embodiment to form a seal element suitable for the sealing assembly300presented herein. In fact, in embodiments, certain seal element features may render a seal element suitable for specific closure elements or casing segments, as is discussed in further detail below.

Now turning toFIGS.5and6, these Figures are diagrammatic/schematic illustrations of seal elements and do not necessarily depict accurate dimensions/relationships of features thereof. Moreover,FIGS.5and6depict similar embodiments with many like parts and are labeled with many like numerals. Thus, any such description of like parts should be understood to apply to both embodiments unless otherwise explicitly stated. As an example of a similarity, seal elements320and320′ each extend from a downstream end323to an upstream end322. Although these ends are defined by different portions of elements320and320′, in both embodiments, the seal elements320and320′ have an overall length that will extend over at least a portion of a lateral surface314of the sealing portion310of the closure element302.

Seal elements320and320′ each also include an internal surface324and324′, respectively, that abuts the lateral surface314when one of the seal elements320and320′ is installed around a closure element302(again, for simplicity, closure element302is used as an example and should be understood to be representative of any closure element unless otherwise indicated). Still further, in the depicted embodiments, seal elements320and320′ each include an external surface325that includes or defines at least one protruding seal3251. In the depicted embodiment, aside from the at least one protruding seal3251, the external surface325is substantially planar (e.g., flat). However, in other embodiments, the external surface325of seal element320, seal element320′, or any other embodiment thereof, may be linear, sloped, or shaped in any other desirable manner.

InFIG.5, the exterior surfaces of seal element320(e.g., downstream end323, upstream end322, internal surface324, and external surface325) are defined by three components: a first seal carrier328(1), a second seal carrier328(2), and a seal ring326. In the depicted embodiment, seal carriers328(1) and328(2) are identical components and each define a flat exterior surface329and a flat interior surface327that is parallel to the exterior surface329. The seal ring326also includes an internal surface3262and an external surface3261. The external surface3261defines the at least one protruding seal3251.

More specifically, the external surface3261of the seal ring326protrudes above, but transitions smoothly from, the flat exterior surfaces329of seal carriers328(1) and328(2) to define the at least one protruding seal3251. However, collectively, external surfaces329and3261define the external surface325of the seal element320. Meanwhile, the internal surface3262of the seal ring326aligns with the flat interior surface327of seal carriers328(1) and328(2) to define the flat internal surface324of the seal element320. That said, in other embodiments, the seal element320can be formed from separate elements of different shapes and sizes, with or without defining a flat internal surface324and/or an external surface325with a flat surface that smoothly transitions to a protruding seal3251, provided at least one at least one protruding seal3251is defined.

By comparison, inFIG.6, the seal element320′ includes two seal elements: a first seal ring326′ that protrudes from an external surface325of the seal element320; and a second seal ring321that protrudes an internal surface324of the seal element320. This arrangement of seals allows seal element320′ to seal against a flat lateral surface314included on the closure element while also sealing against a flat surface of a casing segment (e.g., segment2124, segment2224, or segment2226). That is, this arrangement of seals allows the seal element320′ to be sandwiched between and seal against both a closure element302and casing segment without necessarily modifying or machining the closure element302or the casing segment. As mentioned above,FIG.6is merely one example of this dual-seal arrangement (i.e., seals on opposing lateral surfaces) and a dual-seal arrangement could also be included in other embodiments, such as the embodiment ofFIG.5. For example, seal carrier328(1) and/or seal carrier328(2) could be replaced with a seal ring326arranged in an upside-down orientation as compared to the seal ring326depicted inFIG.5.

In any case, with the arrangement depicted inFIG.6, the exterior surfaces of seal element320′ (e.g., downstream end323, upstream end322, internal surface324′, and external surface325) are defined by three features: a pocketed seal carrier328, the first seal ring326′, and the second seal ring321. Again, the external surface3261of the first seal ring326′ protrudes above, but transitions smoothly from, the flat exterior surface329of the seal carrier328. Thus, surfaces329and3261collectively define the external surface325of the seal element320with at least one protruding seal3251. However, now, the first seal ring326′ sits within a pocket340defined by the seal carrier328so that the seal carrier328supports and/or carries the first seal ring326′. Thus, the internal surface3262of the first seal ring326′ sits above an elongate section341of the seal carrier328. Consequently, the internal surface3262of the first seal ring326′ is spaced from and does not wear against the closure element302(at least in the depicted embodiment).

The internal surface324is substantially similar to the external surface325at least because an external surface3211of the second seal ring321protrudes below, but transitions smoothly from, the flat interior surface327of the seal carrier328. Thus, surfaces327and3211collectively define an internal surface324of the seal element320with at least one protruding seal3252. Again, the second seal ring321sits within a pocket3401defined by the seal carrier328so that the seal carrier328supports and/or carries the second seal ring321. Thus, the internal surface3212of the second seal ring321sits above an elongate section3410of the seal carrier328and the internal surface3212of the second seal ring321is spaced from and does not wear against a casing segment (at least in the depicted embodiment).

Additionally, inFIG.6, the seal carrier328includes a wall3281upstream of the first seal ring326′ and a wall3282downstream of the second seal ring321. Thus, the seal carrier328substantially encapsulates three sides of both the first seal ring326′ and the second seal ring321. However, in other embodiments, a “pocketed” seal carrier328may only border two sides of the first seal ring326′ and/or the second seal ring321. For example, the upstream side of the first seal ring326′ may be accessible from exterior of the seal element320′ and could, for example, engage a retaining ring330. Additionally or alternative, the downstream side of the second seal ring321may be accessible from exterior of the seal element320′ and could, for example, engage the flange304of closure element302. That said, to reiterate, the embodiment depicted inFIG.6is merely an example and, in other embodiments, the seal carrier328may be formed from two or more seal carrier components. For example, one potential construction may include a component resembling seal carriers328(1) and328(2) sandwiched between two additional components with one, two, or no walls forming at least a portion of pockets340and/or3401(example divisions are illustrated by dashed lines inFIG.6). As another example, seal carrier328might be formed from two components, with a split illustrated by one of the dashed lines ofFIG.6.

In fact, any of seal carriers328,328(1), and328(2) can be formed from or replaced by any number of seal carriers, of any lengths (insofar as length denotes the dimensions extending in an x-direction of the drawings, when viewed in a portrait orientation), and seal carriers of shorter lengths may add more granularity to the seal placement options. Put another way, with the sealing assembly300presented herein, the seal element320can create sealing positions along an axial dimension (e.g., “length”) of the seal element320and these positions may achieved with one or more seal carriers of any size and seals of any size. For example, a seal ring326might be able to move axially downstream or axially upstream in minimal axial increments of ⅛ inches. Thus, a number of possible arrangements may be determined based primarily on the length of seal element320and/or a length of the lateral surface314on which the seal element320is to be installed. By comparison, as mentioned above, closure elements with multiple grooves must include fin-like structures between grooves and thickness limitations imposed on these fin-like structures limit the number of sealing positions, as well the placement of sealing positions, that can be achieved along a certain bore length.

Finally, but perhaps most importantly, inFIGS.5and6, the at least one protruding seal3251is illustrated proximate, if not adjacent (i.e., abutting) the upstream end322of the seal element320, but this position is merely an example of a first position and should not be understood to be limiting in any way. As is described in detail below, seal element320and seal element320′ are each long enough to allow different positions/configurations that dispose first seal ring326/326′ and/or second seal ring321in different axial locations along the length of the seal element320/320′.

For example, seal element320ofFIG.5could be reconfigured to place the seal ring326: (a) at the upstream end322of seal element320, with seal carriers328(1) and328(2) downstream of seal ring326; (b) at the downstream end323of the seal element320, with seal carriers328(1) and328(2) upstream of seal ring326; or (c), in a middle portion of seal element320, with seal carriers328(1) and328(2) upstream and downstream of seal ring326, respectively, sandwiching seal ring326. On the other hand, the seal element320′ ofFIG.6could be reconfigured to: (a) position the first seal ring326′ at the upstream end322of seal element320′ and simultaneously position the second seal ring321at the downstream end323of the seal element320′; or (b) position the first seal ring326′ at the downstream end323of seal element320′ and simultaneously position the second seal ring321at the upstream end322of the seal element320′ (e.g., by reversing the orientation in which the seal element320′ is installed on a closure element302and/or in a casing segment). In any case, reconfiguring and/or replacing the seal element may move the seal element axially within the seal ring, such as by moving a seal element axially downstream.

Additionally or alternatively, different sets or kits of seal rings can be manufactured to locate the seal ring326′ in different axial locations, e.g., by creating the pocket340in different axial locations. Thus, in some embodiments, the seal ring326may be moved axially by switching locations of pieces/parts of the seal ring. Additionally or alternatively, at least a portion of the seal element can be replaced to reposition the seal ring. Indeed, if the seal ring326/326′ wears out while in a first axial position, seal ring326/326′ will need to be replaced regardless of whether pieces of the seal element320/320′ can be reconfigured to change the axial position of the seal ring326/326′.

Now turning toFIGS.7A and7B, as yet another non-limiting example, in some instances, the seal element may be a single, unitary component. Seal element320″ illustrates an example one-piece embodiment. Aside from its one-part construction, seal element320″ is substantially similar to seal element320and320′. Thus, like parts are again labeled with like numerals and any such description of like parts included herein should be understood to apply to seal element320″ unless otherwise explicitly stated.

The most notable difference between seal elements320,320′, and320″ is perhaps one of perspective. Since seal element320″ is a one-piece seal element, an exterior surface329of seal element defines at least one protruding seal3251and a flat external surface325instead of being defined by these surfaces. However, that said, seal element320″ still includes at least one protruding seal3251, an internal surface324configured to engage a lateral surface314of a closure element302(again, these are representative examples), an upstream end322, and a downstream end323. Moreover, for the purposes of this application, the portions of seal element320″ adjacent seal3251(e.g., the portion between surfaces324and325and/or the portion downstream of seal3251) may be referred to as seal carriers, even though they are formed integrally with the seal3251.

To reiterate, althoughFIGS.7A and7Bdepict the at least one protruding seal3251proximate the downstream end323of the seal element320″, this position is merely an example of one possible seal position (e.g., a last position) and should not be understood to be limiting. Likewise, althoughFIGS.7A and7Bdepict the at least one protruding seal3251as the only seal, this is merely an example and should not be understood to be limiting (e.g., other embodiments of monolithic seal elements320″ may include an interiorly extending seal). However, regardless of any variation or modifications, since seal element320″ is a one-piece part, seal element320″ does not include a removable/repositionable seal ring. Thus, to move the at least one protruding seal3251(or any other seal included therein/defined thereon) axially along the length of a closure element, the seal element320″ is either flipped/reversed or replaced with a seal element320″ that has the at least one protruding seal3251in a different axial position (e.g., so that the seal3251moves in a downstream or upstream direction over time). That said, the different axial positions can still be achieved with a single closure element, which provides cost savings (e.g., due to less machining) and spacing advantages as compared to solutions that use a closure element with multiple grooves.

Still further, and now referring generally to at leastFIGS.5,6,7A, and7B, although the seal elements presented herein are largely described as having a protruding seal, this description should not be understood to mean that other portions of the seal elements do not or cannot form a seal. For example, in some embodiments, seal3251, the seal ring326/326′ defining this seal3251, and/or seal ring321is/are formed from a soft sealing component, such as rubber. Meanwhile, other portions of the seal element are formed from a comparatively harder material, such as plastic, that may still be able to seal against the casing206and/or closure element. Thus, in some embodiments and/or configurations, the seal elements presented herein may form a stack of seals, e.g., with at least some seals “backing up” seal3251and/or seal321.

In the embodiments ofFIGS.5and6, these different materials may be incorporated into a single seal element320/320′ by manufacturing portions of the seal element320/320′ from different materials. Then, the different portions may be stacked onto each other (e.g., during insertion into a casing segment and/or onto a closure element), removably coupled together, and/or fixedly coupled together. By comparison, in the embodiments ofFIGS.7A and7B, these different materials may be incorporated into a single seal element320with manufacturing processes capable of forming a single piece with two different materials, such as overmolding techniques. In some instances, these manufacturing processes may also be used to form the seal element embodiments ofFIGS.5and6, or at least portions thereof.

Now turning toFIGS.8A-8C, these Figures illustrate an example method of using the sealing assembly300presented herein to movably and/or progressively seal an externally open segment of a fluid end104. For simplicity, these Figures only illustrate movably and/or progressive sealing of segment2224(e.g., progressive sealing with a suction plug), even though any casing segment could be sealed in the same manner. Additionally, and also for simplicity, the Figures illustrate the progressive sealing with closure element302(ofFIG.4A) and seal element320(ofFIG.5) even though it might be achieved with any combination of closure element(s) and seal element(s) presented herein, or variations thereof. Generally, the movable and/or progressive sealing is achieved by moving a repositionable seal axially in a gap between a closure element and a casing segment. Thus, over time, the repositionable seal (or replacement seals therefor) engages different, non-worn portions of the casing206and/or the closure element, allowing for high-performance sealing over an extended period of time (e.g., over the life of the fluid end).

InFIGS.8A-8C, the progressive sealing moves progressively downstream. However, this sealing progression is merely an example and the seal can move axially in any desired manner, including progressively upstream, by moving to positions that vary upstream and downstream movement, etc. That, is, althoughFIGS.8A-8Cillustrate a seal moving progressively downstream, this is merely one example of axial movement and any description of progressive downstream seal movement included in this application should not be understood to limit the seal movement pattern in any way.

In fact, while progressive downstream axial movement of the seal may protect progressive sealing positions from exposure to pumped fluid and debris, moving the seal position upstream may also seal against unworn sections of the casing. This is because wear often focuses at the point at which a seal is formed (e.g., wear is often localized at the point of contact between a seal element and a casing). Thus, moving the seal axially upstream may still achieve seal advantages described herein in connection with moving a seal axially downstream. Indeed, regardless of how the seal position moves over time (e.g., progressively upstream, progressively downstream, or any other axial movement pattern), the closure element302need not include any grooves (which may be difficult and/or costly to machine). Moreover, since the seal positions are defined without grooves, multiple seal positions can be achieved over a small section of the casing206(e.g., seal positions that are very close together).

InFIG.8A, the fluid end104is illustrated prior to a first activation. As can be seen, prior to a first activation, a seal element320with a seal ring326disposed at, or at least proximate to, an upstream end322of the seal element320is installed onto the closure element302. That is, initially, the sealing assembly300is formed by installing a seal element320configured in a first configuration C1onto the closure element302. In the depicted embodiment, the seal element320is retained on the closure element302with the retaining ring330. Thus, for example, the seal element320may be slid onto the lateral surface314of the closure element302until it abuts the bottom or distal surface308of the flange304(i.e., the underside of flange304). Then, the retaining ring330may be slid to the lateral surface314of the closure element302until it abuts the seal element320, locking the seal element320into place on the lateral surface314between the flange304and the retaining ring330.

Regardless of how the seal element320is formed, once the seal element320is installed around the closure element302in a first configuration C1, the sealing assembly300can be installed in an externally open segment (i.e., a segment open to external surface210), which is segment2224in the depicted embodiment. For example, the sealing assembly300may be pressed or pushed into segment2224into a secure position P1. Alternatively, the seal element320can be installed in the segment2224and then the closure element may be pushed into the segment2224and the seal element320so that the sealing assembly300is formed in the segment2224, in a secure position P1. Either way, in at least some embodiments, including the depicted embodiment, the sealing assembly300is in the secure position P1when a flange304of the sealing portion310sits on a set of the segment. Then, the sealing assembly300may be secured therein by a retaining element500.

However, as mentioned, inFIG.8A, the seal element320is one example of a sealing assembly300configured in the first configuration C1. In other embodiments, a monolithic seal element320″ with at least one protruding seal3251disposed at, or at least proximate to, the upstream end322could be installed in a gap between the closure element302and a wall of segment2224to achieve the first configuration C1. Likewise, a seal element320′ (e.g., a seal element with a pocketed seal carrier328) could be installed in a gap between the closure element302and the segment2224with the at least one protruding seal3251is disposed at, or at least proximate to, the upstream end322of seal element320′ to achieve the first configuration C1.

In any case, when the sealing assembly300is in the secure position P1, the lateral surface314of the sealing portion310of the closure element302faces an interior wall of the externally open segment (e.g., segment2224). Thus, installing the sealing assembly300in an externally open segment positions the seal ring326to seal against a first portion of an interior wall of the externally open segment (e.g., segment2224). This closes the segment and prevents pumped fluid from traveling to the external surface210of the casing206via the segment.

Once all segments of the fluid end104are closed or connected to the appropriate piping/conduits (with the sealing techniques presented herein or other techniques), a power end of the reciprocating pump may be activated. Activating the power end drives pistons to pump fluid through the fluid end104. That is, activating the power end pumps abrasive fluid through pumping chamber208in a cyclical fashion. Over time, abrasive elements (e.g., sand) can get wedged between seal components (e.g., seal ring326and the metal casing206) and/or remove metal from the casing206and cause seal to leak or fail. If these seals fail, a high pressure stream of fluid can exit the fluid end, which is dangerous for operators, the overall pump, and potentially for the environment. Thus, over time, users monitor the fluid end104for leakage or other signs of deterioration. The sealing assembly300may also be examined when other parts of fluid end104are serviced.

When it comes time to change the sealing assembly300, the power end is deactivated. Then, the sealing assembly300can be removed from its segment (e.g., segment2224) and the seal element320can be reconfigured to a second configuration C2. Alternatively, in some embodiments, it may be possible to reconfigure the seal element320to a second configuration C2while the sealing assembly300, or a portion thereof, is installed in a segment (e.g., segment2224).

As can be seen inFIG.8B, when the sealing assembly is reconfigured to a second configuration C2, the seal element320is still positioned in a central axial position. More specifically, in the depicted embodiment, the seal ring326is positioned about halfway between the upstream end322and downstream end323of the seal element320. However, in other embodiments, the seal ring326may be positioned closer to end or the other when in the second configuration C2. In any case, when the sealing assembly300is reinstalled in segment2224in position P1(the same position asFIG.8A) with the seal element320in the second configuration C2, the seal ring326will be positioned to seal against a second portion of the interior wall of segment2224, such as a portion that is downstream of the portion engaged by the seal ring326in the first configuration C1.

As an example of a sealing assembly300configured in the second configuration C2,FIG.8Billustrates the sealing assembly300being configured in the second configuration C2by positioning a seal ring326between a first seal carrier328(1) and a second seal carrier328(2). However, in other embodiments, the seal element320could be configured in the second configuration C2by positioning the seal ring326in a pocket340of a seal carrier328that defines the pocket in a position downstream of the first seal position (e.g., in a central position). That is, a seal carrier328may include an elongate section341extending between two rectangular sections to position a seal ring326′ in a position downstream of the first seal position. Still further, in other embodiments, sealing assembly300may be configured in the second configuration C2by replacing a first seal element320with a monolithic seal element320″ with at least one protruding seal3251disposed in a position downstream of the first seal position (e.g., in a central position).

Importantly, in the depicted axial progression, a seal326of the first configuration C1protects the portion of the casing against which the seal326of the second configuration C2seals because the seal position in the first configuration C1is upstream of the seal position in the second configuration C2positions. That is, a seal326of the first configuration C1may prevent high pressures and abrasive fluids from acting on the portion of the casing that the seal326seals against in the second configuration C2. Thus, when the seal element320is reconfigured from a first configuration C1to a second configuration C2, the seal ring326may seal against a fresh (i.e., unworn) portion of the casing206(the portion defining an interior wall of the segment in which the sealing assembly300is installed).

Once the sealing assembly300is reinstalled in the fluid end104in its second configuration C2, the fluid end104may be fully sealed (assuming other seals have not been removed), and the power end can be reactivated to cause the fluid to flow through the fluid end104again. Thus, the techniques presented herein may provide a highly effective and efficient of servicing covers, plugs, and/or sleeve that minimizes down time for the pump.

Then, if the sealing assembly300starts to leak or otherwise fail again (e.g., before the fluid end104reaches the end of its useful life), the power end can be deactivated again and the sealing assembly can be removed from its segment (e.g., segment2224) so that the seal element320can be reconfigured to a third configuration C3, as is shown inFIG.8C. Alternatively, in some embodiments, it may be possible to reconfigure the seal element320to a third configuration C3while the sealing assembly300, or at least a portion thereof, is installed in a segment (e.g., segment2224).

As can be seen inFIG.8C, when the seal element320is reconfigured to a third configuration C3, the seal element320is positioned in a third axial position, which may be referred to as a downstream axial position. More specifically, in the depicted embodiment, the seal ring326is positioned proximate the downstream end323of the seal element320, axially downstream of the position of the seal ring326in both the first configuration C1and the second configuration C2. Thus, when the sealing assembly300is reinstalled in segment2224in position P1with the seal element320in the third configuration C3, the seal ring326will be positioned to seal against a third portion of the interior wall of segment2224. In the depicted embodiment, the third portion of the interior wall is downstream of the portions engaged by the seal ring326in the first configuration C1and the second configuration C2.

Again, inFIG.8C, the seal element320is one example of a sealing assembly300configured in the first configuration C3. In other embodiments, a monolithic seal element320″ with at least one protruding seal3251disposed at, or at least proximate to, the downstream end323could be installed in a gap between the closure element302and the interior wall of segment2224to achieve the third configuration C3. Likewise, a seal element320′ (e.g., a seal element with a pocketed seal carrier328) could be installed in a gap between the closure element302and the segment2224with the at least one protruding seal3251disposed at, or at least proximate to, the downstream end323of seal element320′ to achieve the third configuration C3. Additionally or alternatively, the third configuration C3may be a mirrored configuration of the first configuration C1. Thus, in some embodiments, the third configuration C3can be attained by flipping the seal element320of the first configuration C1upside down. As mentioned, in some instances, the seal ring326may wear during use in a first configuration. Thus, even if the third configuration C3can be achieved by flipping the seal element320of configuration to a mirrored orientation, it may still be necessary to replace the seal ring (e.g., seal ring326or326′) as part of the reconfiguration.

Regardless of how the third configuration C3is achieved, the earlier seals of configurations C1and C2may protect the portion of the casing against which the seal326of the third configuration C3seals. That is, the seal ring(s)326of the first and second configurations C1and C2may prevent high pressures and abrasive fluids from acting on the portion of the casing that the seal326seals against in the third configuration C3. Thus, when the seal element320is reconfigured to a third configuration C3, the seal ring326may seal against a fresh (i.e., unworn) portion of the casing206(the portion defining an interior wall of the segment in which the sealing assembly300is installed).

Once the sealing assembly300is reinstalled in the fluid end104in its third configuration C3, the fluid end104may be fully sealed (assuming other seals have not been removed), and the power end can be reactivated to cause the fluid to flow through the fluid end104again. Notably, in at least some embodiments, the seal ring326will be configured to have a lifespan that is at least one-third of the lifespan of the casing206. Thus, after two reconfigurations (e.g., from configuration C1to C2and from configuration C2to C3), the fluid end may reach the end of its useful life and no further reconfigurations may be required. At this point, the sealing assembly300can be transferred to a new fluid end104or disposed of.

Now referring generally toFIGS.8A-8C, in at least some instances, the various seal elements (or components thereof) needed for reconfiguration may be provided in a kit. For example, a kit may include one closure element302and two seal elements320designed to configure the sealing assembly in the first configuration C1and the second configuration C2(or the third configuration C3). Alternatively, a kit may include one closure element302and three seal elements320designed to configure the sealing assembly in the first configuration C1, the second configuration C2, and third configuration C3. In some instances, the two or more seal elements may be color coded to provide indications of configurations (e.g., configuration C1seal elements are green, configuration C2seal elements are yellow, and configuration C3seal elements are red).

Regardless of the number and coloring of seal elements included in a kit, the seal elements in a kit may be variations of the same embodiment. For example, in some embodiments, all of the two or more seal elements in a kit may be rearranged version of the seal element320depicted inFIG.5. Thus, as an example, a first seal element may include a seal ring326downstream of two or more seal carriers, a second seal element may include a seal ring326disposed between seal carriers, and a third seal element may include a seal ring326disposed downstream of the two or more seal carriers. Alternatively, a kit may include seal elements from multiple embodiments. For example, a first seal element of a kit may be formed in accordance with the embodiment the seal element320depicted inFIG.5, a second seal element of the kit may be formed in accordance with the embodiment the seal element320depicted inFIG.6, and a third seal element of the kit may be formed in accordance with the embodiment the seal element320depicted inFIGS.7A and7B. As another example, two seal elements may be formed from one embodiment and one or more additional seal elements may be formed from another embodiment.

Still further, in some instances, the kit need not include only fully formed seal elements and can include portions thereof. For example, a kit may include two seal carriers (e.g., seal carriers328(1) and328(2)) and three seal rings326. Then, if necessary, the seal ring326can be replaced during three reconfigurations of the sealing assembly300. As another example, a kit may include three seal rings326′ and two pocketed carriers328. One of the carriers328may include a central pocket and the other carrier328may have an edge pocket that can be flipped to provide a downstream or upstream pocket. Then, the kit can be used to reconfigure a sealing assembly300between configurations C1, C2, and C3while replacing the seal ring326′ during each reconfiguration (if necessary).

Now turning toFIGS.9-13, these Figures illustrate examples where different embodiments of the sealing techniques presented herein are utilized to provide repositionable sealing. In some of these embodiments, the sealing assembly includes a different closure element as compared to the embodiment depicted inFIGS.8A-8C. Additionally or alternatively, in some of these embodiments the sealing assembly seals against different casings as compared to the casing depicted inFIGS.8A-8C(andFIG.2). At a high-level,FIGS.9-13depict different sealing assemblies being used with a casing that includes a segment that is stepped adjacent the closure element. Thus, the casing defines a seat that can at least partially secure a seal element of a sealing assembly between the casing and a closure element. Moreover, some of these embodiments incorporate closure element302′ in the sealing assembly, while other embodiments incorporate a modified version of closure element302′, for example, to provide additional seal points between the closure element and the seal element of the sealing assembly.

For brevity, the description ofFIGS.9-13included below focuses on differences between these embodiments, as compared to each other and previously described embodiments. However, before turning to this description, it should be noted that although casings of these embodiments—casing206(1), casing206(2), casing206(3), and casing206(4)—are not shown in their entireties, the casings are each substantially similar to casing206. The main difference between casings206(1)-206(4) and casing206is that casings206(1)-206(4) are each shaped to define a seat. Specifically, segment2224(1) of casing206(1) defines seat450, segment2224(2) of casing206(2) defines seat450′, segment2224(3) of casing206(3) defines seat450′ and a secondary seat451, and segment2224(4) of casing206(4) defines seat452.

Thus, any description of casing206included above should be understood to apply to casings206(1)-206(4) unless otherwise explicitly stated (i.e.,206(1)-206(4) may each have a plurality of pumping chambers that are each defined by four intersecting segments). Moreover, to be completely clear, althoughFIGS.9-13depict sealing assemblies in one or two configurations (e.g., first configuration C1forFIGS.9-11and a first configuration C4and a second configuration C5inFIGS.12and13), these configurations are merely examples. Embodiments including the features depicted inFIGS.9-13may allow seal elements to be positioned is in any desired configuration or position in any manner described herein.

Now turning toFIG.9specifically, in this embodiment, a sealing assembly300(1) is formed from the same seal element320as the sealing assembly300ofFIGS.8A-8C(e.g., seal element320ofFIG.5), but this seal element320is installed on closure element302′ (e.g., ofFIG.4B). Consequently, the upstream end322of the seal element is not secured against a retaining ring330. Instead, sealing assembly300(1) is installed within a casing206(1) that includes a segment2224(1) that defines a seat450. That is, segment2224(1) is stepped.

Thus, the upstream end322of the seal element320sits in and can rest on the seat450, and the seat450can prevent axial movement of the seal element320towards the pumping chamber208(seeFIG.2). Meanwhile, a downstream end323of the seal element abuts the bottom or distal surface308of the flange304so that the seal element320is axially secured between (i.e., “axially sandwiched”) between the flange304and the seat450. Then, the seal326can be repositioned over the axial distance between the flange304and the seat450to provide the repositionable sealing presented herein, for example, by progressively moving in a downstream direction.

InFIGS.10and11, the casings are again stepped, but casing206(2) includes a segment2224(2) with a single step to define a seat450′ while casing206(3) includes a segment2224(3) with two steps to define seat450′ and a secondary seat451that extends from a downstream end of seat450′. In different embodiments, seat450′ may have different dimensions as compared to seat450ofFIG.9. Meanwhile, the secondary seat451may accommodate a flange of a seal element to further secure a seal element between the casing and closure element302.

Additionally, the embodiments depicted inFIGS.10and11differ from the embodiments ofFIGS.8A-8C and9because the sealing assemblies are slightly different. First, the sealing assembly300(2) ofFIG.10includes: (1) a seal element320″ that is a modified version of seal element320′ (ofFIG.6); and (2) a closure element302″ that is a modified version of closure element302′ (ofFIG.4B). One main difference between seal element320″ and seal element320′ is that seal element320″ does not include the second seal ring321. Instead, the closure element302″ includes a seal3021disposed in a single groove. That is, closure element302″ includes a single-pocketed seal carrier328′. Meanwhile, one main difference between closure element302″ and closure element302′ (ofFIG.4B) is that the lateral surface314of the sealing portion310of closure element302″ includes a groove with a protruding seal3021. Consequently, from one perspective, the second seal ring321of seal element320′ is transferred from seal element320″ to the closure element302″.

Second, the sealing assembly300(2)′ ofFIG.11includes: (1) a seal element320′″ that is a modified version of seal element320″ (ofFIG.10); and (2) the same closure element302″ asFIG.10. One main difference between seal element320′″ and seal element320″ is that seal element320′″ includes a radial extension3283at its downstream end323. Radial extension3283extends radially outwards and, thus, when seal element320′″ is disposed around closure element302″, the radial extension3283extends along the bottom or distal surface308of the flange304, into the secondary seat451. Consequently, radial extension3283may be secured between the casing206(3) and the flange304, and may further secure the downstream end323of the seal element320′″ in a particular axial location.

Regardless of the differences between the embodiments ofFIGS.10and11, the seal3021between the closure element302″ and the320″ remains fixed in place as long as the closure element302′ remains in place. Meanwhile, seal326can be repositioned axially within the pocketed carrier328′ in accordance with any of the techniques presented herein. For example, the seal326can be axially repositioned by flipping the orientation of the pocketed carrier328′ from the orientation shown in configuration C1. Alternatively, the seal326can be axially repositioned by replacing the pocketed carrier328′ with a pocketed carrier328′ that has a pocket in a different axial position. In any case, the interior seal3021may remain fixed as the seal326between the320″ and the segment2224(2) is axially repositioned. Alternatively, the closure element302″ could be replaced to axially reposition seal3021, either when the seal326is axially repositioned or independent of the axial repositioning of seal326.

InFIGS.12and13, a casing206(4) with a segment2224(4) again defines a seat452, but now the seat452is wider than the seat450′ ofFIGS.10and11or the seat450ofFIG.9. This allows the segment2224(4) to accommodate a sealing assembly300(3) formed from closure element302and seal element320′. As can be seen, when sealing assembly300(3) is installed in a casing in a first configuration C4, the second seal ring321is disposed downstream of the first seal ring326′. Then, to axially reposition second seal ring321and/or seal ring326, the sealing assembly300(3) can be flipped into a second configuration C5(e.g., removed, turned around and reinserted upside down as compared to its previous orientation) where the second seal ring321is disposed upstream of the first seal ring326′.

Now turning toFIGS.14-16for a description of how the techniques presented herein may be used while providing a repositionable seal for a movable closure element. For simplicity,FIGS.14-16show a packing600installed directly into segment2226without a sleeve therebetween, but this is not intended to be limiting. In fact, packing600may implement the techniques presented herein when installed without a sleeve, when installed within a sleeve-style sealing assembly300, or when installed within a conventional sleeve. Thus, packaging600may realize the advantages of the techniques presented herein in a variety of situations/arrangements.

In the depicted embodiment, packing600extends around a plunger202, within stuffing box2227. The packing600includes a number of sealing and/or scraping elements that are generally denoted herein as packing elements602and these packing elements602are axially secured within the stuffing box2227by one or more junk rings640and a lantern ring650. In the depicted embodiment, the packing elements602include three rings. However, this is merely an example and in other embodiments, packing elements602may include any number of rings in any order or combination and any of the rings may include any desirable features or structures. Regardless of the number, shape, size, and/or configuration of rings in the packing elements602, the one or more junk rings640are disposed upstream of the packing elements602. Meanwhile, the lantern ring650disposed downstream of the packing elements602, between the packing elements602and the retaining element800which, in the depicted embodiment, is secured to the segment2226via threads2229. Thus, the one or more junk rings640and a lantern ring650axially enclose (i.e., axially sandwich) the packing elements602in the stuffing box2227.

For the purposes of this application, the one or more junk rings640and the lantern ring650may be referred to as seal carriers. This is because the one or more junk rings640and the lantern ring650may control an axial position of seals formed by the packing elements602. Consequently, the one or more junk rings640and the lantern ring650may serve an analogous purpose to and/or be reconfigured in the same manner as seal carriers328(1),328(2), seal carrier328, and/or variations thereof. On the other hand, for the purposes of this application the plunger202may be referred to as a movable closure element. This is because the one or more junk rings640, the lantern ring650, and the packing elements602extend around the plunger202and cooperate with the plunger to close segment2226. Thus, collectively, the packing300and the plunger202may form a sealing assembly300(4) that can function in accordance with, and realize the advantages of, the techniques presented herein.

With that terminology in mind, in a first configuration C6, the lantern ring650and one or more junk rings640position the packing elements602in a first axial position. In this position, the packing elements602seal against a first portion of segment2226(but this could be a first portion of a sleeve if a sleeve were disposed between packing600and segment2226). Additionally, in the first axial position, the packing elements602may seal against a first length of plunger202, depending on the stroke length of the plunger202. Thus, over time, the segment2226and/or the plunger202might wear in locations that contact the packing elements602in their first axial position. After a certain amount of wear, the lantern ring650and one or more junk rings640can be replaced with a lantern ring652and one or more junk rings641to reconfigure the packing600in a second configuration C7.

In the second configuration C7, the lantern ring652and one or more junk rings641position the packing elements602in a second axial position. In this position, the packing elements602may seal against a second portion of segment2226(but this could be a second portion of a sleeve if a sleeve were disposed between packing600and segment2226). Additionally, in the second axial position, the packing elements602could potentially seal against a second length of plunger202, depending on the stroke length of the plunger202. Thus, by reconfiguring the packing600form the first configuration C6to the second configuration C7, the segment2226and/or the plunger202might wear in different locations over time, realizing the advantages of repositionable seals discussed herein.

While the invention has been illustrated and described in detail and with reference to specific embodiments thereof, it is nevertheless not intended to be limited to the details shown, since it will be apparent that various modifications and structural changes may be made therein without departing from the scope of the inventions and within the scope and range of equivalents of the claims. In addition, various features from one of the embodiments may be incorporated into another of the embodiments. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the disclosure as set forth in the following claims.

It is also to be understood that the sealing assembly described herein, or portions thereof may be fabricated from any commonly used seal materials, such as homogeneous elastomers, filled elastomers, partially fabric reinforced elastomers, and full fabric reinforced elastomers. Suitable resilient elastomeric materials includes, but re not limited to, thermoplastic polyurethane (TPU), thermoplastic copolyester (COPE), ethylene propylene diene monomer (EPDM), highly saturated nitrile rubber (HNBR), reinforced versions of the foregoing materials, such as versions reinforced with fibers or laminations of woven material, as well as combinations of any of the foregoing materials.

Similarly, it is intended that the present invention cover the modifications and variations of this invention that come within the scope of the appended claims and their equivalents. For example, it is to be understood that terms such as “left,” “right,” “top,” “bottom,” “front,” “rear,” “side,” “height,” “length,” “width,” “upper,” “lower,” “interior,” “exterior,” “inner,” “outer” and the like as may be used herein, merely describe points of reference and do not limit the present invention to any particular orientation or configuration. Further, the term “exemplary” is used herein to describe an example or illustration. Any embodiment described herein as exemplary is not to be construed as a preferred or advantageous embodiment, but rather as one example or illustration of a possible embodiment of the invention.

Finally, when used herein, the term “comprises” and its derivations (such as “comprising”, etc.) should not be understood in an excluding sense, that is, these terms should not be interpreted as excluding the possibility that what is described and defined may include further elements, steps, etc. Meanwhile, when used herein, the term “approximately” and terms of its family (such as “approximate,” etc.) should be understood as indicating values very near to those which accompany the aforementioned term. That is to say, a deviation within reasonable limits from an exact value should be accepted, because a skilled person in the art will understand that such a deviation from the values indicated is inevitable due to measurement inaccuracies, etc. The same applies to the terms “about” and “around” and “substantially.”