Valve with replaceable packing seal cartridge

Abstract

The valve includes at least one valve stem seal, such as a packing seal, contained in a removable seal cartridge. The valve stem is connected to an actuator via a linkage and can be removed to provide a coupling gap between the actuator and the valve stem. The seal cartridge can then be slid along the valve stem into the coupling gap and laterally removed from the valve, after which the seal in the seal cartridge can be refurbished. The valve can be a rotary valve or a linear valve. In an embodiment, the coupling gap can be increased by linearly displacing the actuator from the valve stem. The seal cartridge can be reinstalled in the valve after refurbishment, or a substantially identical replacement seal cartridge can be provided and installed in the valve in place of the removed seal cartridge, thereby minimizing valve downtime.

Description

Statement of Government Interest

[0001] Portions of this invention were made with Government funding under Contract No. DE-NA0003525 and the Government may have certain rights.

[0002] This application claims the benefit of U.S. Patent Application No. 17 / 485,678, filed September 27, 2021, the disclosure of which is incorporated herein by reference in its entirety for all purposes. [Technical field]

[0003] The present invention relates to valves, and more particularly to valves including packing seals. [Background technology]

[0004] Valves are widely used to control the flow of fluids through pipes or conduits. Generally, most valves include a valve seat and a valve plug located within a valve body of the valve, which includes a valve stem that is coupled in some manner to a valve actuator. Typically, the valve stem extends into a valve "bonnet" that is attached and sealed to the valve body. Most valves are either rotary valves, where the valve plug is rotated within the valve seat by a valve actuator, or linear valves, where the valve plug is shifted linearly toward or away from the valve seat.

[0005] Generally, it is necessary to ensure that process fluid does not leak along the valve stem and out of the valve, while at the same time ensuring that the valve stem can rotate and / or slide without undue obstruction. The most widely used approach is to use one or more "packing" seals to form a seal around the valve stem. A packing seal includes a rope of lubricated sealing material that wraps around the valve stem, filling the dead space and forming a seal with the valve stem. Over time, however, as the packing material begins to wear and lubrication decreases, process fluid can leak past the packing seal. If the process fluid is liquid at high temperatures but solidifies at low temperatures, a leak in the packing can cause the normally liquid process fluid to cool and solidify in the packing bore, causing the valve to seize and become inoperable. Preventive measures against such leakage may include periodic relubrication of the packing material, and eventually refurbishing or replacing the valve.

[0006] It is often preferable to periodically refurbish packing seals when valve replacement is inconvenient or expensive. However, while refurbishment of a valve's packing seals avoids the expense of purchasing an entire replacement valve, the refurbishment costs can still be high, not only for the refurbishment itself, but also due to lost productivity while the valve is out of service during the refurbishment. Therefore, it may be desirable to refurbish a valve's packing seals as soon as possible.

[0007] Unfortunately, refurbishing a valve's packing seal can be complicated and time-consuming. For example, accessing the packing seal often requires disassembly and / or removal of various other parts of the valve unrelated to the packing seal, such as the valve actuator, bonnet, and / or various valve accessories. Also, worn and leaking valve packing can be difficult to replace. For example, the packing ring may become embedded deep within the packing bore and be difficult to extract, especially if the process fluid is sticky or solidified. And if the packing bore is damaged, further repairs and / or replacement may be required.

[0008] Therefore, there is a need for a valve design that allows for quick and easy replacement of packing seals. Summary of the Invention

[0009] The present invention is a valve design that allows for quick and easy replacement of packing seals.

[0010] In accordance with the present invention, a valve stem of a valve is sealed by one or more packing seals that surround the valve stem, for example, in a gland area of ​​the valve. Inclusion of the packing seal in a removable seal cartridge allows for easy and quick removal of the packing seal from the valve. In various embodiments, the seal cartridge also includes one or more of a valve stem guide, a spacer, a gland follower, a gland flange, and a live-load spring.

[0011] In accordance with the present invention, the actuator is connected to the valve stem via a removable linkage, sometimes referred to herein as a valve stem clamp, that is configured to transfer linear and / or rotational movement of the actuator to the valve stem during normal operation of the valve. Because the valve stem clamp is located beyond the packing seal, it does not need to be enclosed within a housing and may be accessible laterally without disassembling any components of the valve. Alternatively, a simple, easily removable cover, such as a split cover, may be provided that serves to keep dirt and debris away from the actuator without unduly impeding lateral access to the seal cartridge.

[0012] When it is desired to remove the seal cartridge, the valve stem clamp is removed from the valve, then the seal cartridge is unlatched from the bonnet and slid along the axis of the valve stem into the interlocking gap previously occupied by the valve stem clamp until the seal cartridge can be removed laterally over the valve stem and out of the valve. Once the seal cartridge is removed from the valve, it can be easily and quickly refurbished in a suitable facility. In addition, it is possible to provide an identical new or previously refurbished seal cartridge that can be quickly reinstalled on the valve so that the valve continues to operate while the original seal cartridge is being refurbished. The newly refurbished seal cartridge can then be kept ready until the next cartridge change is required. As a result, packing seal replacement is quick and easy, minimizing valve downtime.

[0013] In some embodiments, the valve stem clamp is long enough to provide a longer interlocking clearance above the valve stem than the seal cartridge in a single step of removing the valve stem clamp. In other embodiments, if the valve design accommodates linear sliding of the actuator relative to the valve stem, the valve stem clamp can be shorter than the seal cartridge and the difference in length can be made up by sliding the actuator out of the seal cartridge, thereby providing additional space for the seal cartridge to slide over the valve stem.

[0014] The present invention thereby allows the packing seal to be removed from the valve without removing the actuator. Furthermore, replacement of the seal cartridge does not require disassembly of the bonnet from the valve and therefore does not require replacement of the larger bonnet gasket, which is typically more expensive than the small gasket that seals the seal cartridge to the bonnet. Thus, the present invention allows for quicker replacement of the seal packing material, since the packing material is pre-installed in the seal cartridge before the seal cartridge is installed in the valve. This reduces the possibility of improper packing placement, in cases where the packing configuration is complex. The present invention thereby reduces maintenance costs, since replacement of the packing is quick and the seal cartridge is less expensive than the bonnet. It should also be noted that in the present invention, the packing hole, i.e., the outer hole surrounding the packing, is in the seal cartridge, not in the more expensive bonnet. Thus, if the packing hole is damaged, only the seal cartridge needs to be replaced, rather than the more expensive bonnet.

[0015] A first general aspect of the invention is a valve including a valve seat within a valve body, a valve plug configured to control flow of a process fluid through the valve body according to separation between the valve plug and the valve seat and / or according to a rotational position of the valve plug within the valve seat, a valve stem in mechanical communication with the valve plug, an actuator, a removable valve stem linkage providing a mechanical coupling between the actuator and the valve stem such that rotational and / or linear displacement of the actuator is transmitted to the valve stem, and a seal cartridge including a cartridge housing removably attached to the valve body and at least one seal surrounding the valve stem and allowing at least one of linear and rotational movement of the valve stem relative to the seal cartridge while forming a seal between the cartridge housing and the valve stem, wherein removal of the removable valve stem linkage provides an unobstructed coupling gap between the actuator and the valve stem, and removal of the cartridge housing from the valve body allows the seal cartridge to slide along the valve stem into the coupling gap until it no longer surrounds the valve stem, allowing it to be laterally removed from the valve.

[0016] In some embodiments, the valve is a rotary valve, and in other embodiments, the valve is a linear valve.

[0017] In any of the above embodiments, at least one of the seals may be a packing seal.

[0018] In any of the above embodiments, Removable Valve stem linkage is Removable Clamping a lower portion of the actuator on an upper portion of the valve stem linkage; Removable The lower portion of the valve stem linkage may act as a clamp to clamp the upper portion of the valve stem.

[0019] Any of the above embodiments may further comprise: Removable The valve may be configured such that lateral access to the valve stem linkage does not require removal of any components of the valve, or at most lateral access to the valve requires removal of the valve cover, said removal not requiring other disassembly of the valve.

[0020] In any of the above embodiments, the seal cartridge may further include at least one of a valve stem guide, a spacer, a gland follower, a gland flange, and a live load spring.

[0021] In any of the above embodiments, Removable The length of the valve stem linkage is Removable The length may be sufficient to allow removal of the valve stem linkage to remove the seal cartridge from the valve.

[0022] In any of the above embodiments, the valve may allow linear movement of the actuator; Removable The combination of removing the valve stem linkage and linearly displacing the actuator from the valve stem may be sufficient to allow removal of the seal cartridge from the valve.

[0023] In any of the above embodiments, seal Cartridge Ji's The bottom can be secured to the top of the bonnet such that the seal cartridge extends over the bonnet of the valve housing.

[0024] In any of the above embodiments, seal Cartridge Ji's The upper flange of the top portion may be attached to the top of the bonnet of the valve housing such that the seal cartridge extends into the bonnet.

[0025] A second general aspect of the present invention is a method of refurbishing at least one valve stem seal contained within a valve. The method includes providing a valve according to the first general aspect; Removable Remove the valve stem linkage and remove the seal cartridge from the valve body. seal Along the valve stem until the cartridge no longer surrounds the valve stem. seal The method includes sliding the cartridge, laterally removing the seal cartridge from the valve, and refurbishment of at least one seal included in the seal cartridge.

[0026] In an embodiment, the method further includes translating the actuator away from the valve stem, thereby increasing the coupling gap.

[0027] Any of the above embodiments can further include refurbishing at least one seal included in the seal cartridge. In some of these embodiments, the method includes, after refurbishing the seal cartridge, reinstalling the seal cartridge in the valve and then refitting the seal cartridge in the valve. Removable Further including reinstalling the valve stem linkage.

[0028] In any of the above embodiments, a replacement seal cartridge is provided, and after removing the seal cartridge from the valve, the replacement seal cartridge is installed in the valve; Removable It may further include reinstalling the valve stem linkage.

[0029] The features and advantages described herein are not exhaustive, and in particular many additional features and advantages will become apparent to those skilled in the art upon consideration of the drawings, specification, and claims.Furthermore, it should be noted that the language used in this specification has been chosen primarily for purposes of readability and instruction, and not to limit the scope of the inventive subject matter. [Brief description of the drawings]

[0030] [Figure 1] FIG. 1 is an isometric side view of one embodiment of the present invention.

[0031] [Diagram 2] FIG. 2 is an isometric cross-sectional view of a seal cartridge in one embodiment of the present invention shown separated from a valve.

[0032] [Figure 3A] FIG. 3A is an isometric front cross-sectional view of the valve of FIG.

[0033] [Figure 3B] FIG. 3B is an isometric perspective view of the cross-sectional view of FIG. 3A shown rotated about the central axis of the valve stem.

[0034] [Figure 4] FIG. 4 is an isometric close-up view of the portion of the valve of FIG. 3B including the seal cartridge.

[0035] [Figure 5A] FIG. 5A is an isometric side view of the valve of FIG. 1 shown with the valve stem clamp removed from the valve.

[0036] [Figure 5B] FIG. 5B is an isometric side view of the valve of FIG. 5A shown with the seal cartridge slid into the interlocking gap.

[0037] [Figure 5C] FIG. 5C is an isometric side view of the valve of FIG. 5B, with the seal cartridge shown laterally removed from the valve.

[0038] [Figure 6] FIG. 6 is a flow diagram illustrating the method of the present invention.

[0039] [Figure 7] FIG. 7 is an isometric cross-sectional view of one embodiment of the present invention with the seal cartridge installed within the bonnet. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0040] The present invention is a valve design that allows for quick and easy replacement of packing seals.

[0041] 1 and 2, in accordance with the present invention, the valve stem 114 of the valve is sealed by one or more packing seals 200 that surround the valve stem 114, for example, in the gland area of ​​the valve. Including the packing seal 200 as part of the removable seal cartridge 100 allows for easy and quick removal of the packing seal 200 from the valve. In the embodiment of FIG. 2, the seal cartridge 100 further includes a valve stem guide 202, a spacer 204, an upper cartridge flange 206, and a lower cartridge flange 208.

[0042] In accordance with the present invention, the actuator 102 is connected to the valve stem 114 via a removable linkage 104, sometimes referred to herein as a valve stem clamp 104. In the illustrated exemplary embodiment, the valve stem clamp 104 is configured to transmit linear movement of the actuator 102 to the valve stem 114. To this end, a valve stem guide 116 is provided that prevents excessive rotation of the valve stem clamp 104, and thus the valve stem 114 and actuator 102, as the assembly slides up and down. In other embodiments, the valve stem clamp 104 is configured to transmit rotational movement of the actuator 102 to the valve stem 114. In general, the valve stem clamp 104 can be configured to transmit both linear and rotational movement of the actuator to the valve stem 114.

[0043] The valve stem clamp 104 is located above or over the seal cartridge 100 and in the embodiment of FIG. 2, the valve stem clamp 104 is not enclosed within a housing and is accessible laterally without disassembly of any components of the valve. In other embodiments, a simple, easily removable cover (not shown), such as a split cover, is provided that serves to keep dirt and debris away from the actuator without unduly impeding lateral access to the seal cartridge 100. Also shown in FIG. 1 are the valve body 106, bonnet 108, live load spring 118, and actuator yoke 110. The valve of FIG. 1 is a linear valve and further includes a spring housing 112 within which a spring (302 in FIG. 3) exerts an upward linear force on the actuator such that the valve of FIG. 1 is "normally open" when no other force is applied to the actuator.

[0044] FIG 3A is a front cross-sectional view of the embodiment of FIG 1, with the cross-section taken perpendicular to the plane of the front view of FIG 1. FIG 3B is a rotated view of the cross-sectional view of FIG 3A. In these cross-sectional views, the spring 302 can be seen within the spring housing 112, terminating in a spring plate 306 and forming a space 304 that surrounds the spring and is bounded by the spring plate 306 and the bottom of the spring housing 112. These cross-sectional views further show the structure of the valve stem clamp 104 as a pair of plates bolted together, with the bottom end of the actuator sandwiched between the plates at the top of the valve stem clamp 104 and the top end of the valve stem sandwiched between the plates at the bottom of the valve stem clamp 104. FIG 4 is an enlarged cross-sectional view of the area of ​​FIG 3A where the seal cartridge 100 is installed.

[0045] When it is desired to remove the seal cartridge, the valve stem clamp 104 is removed from the valve, leaving an unobstructed interlocking gap 500 between the actuator 102 and the valve stem 114, as shown in Figure 5. The seal cartridge 100 is then removed from the bonnet 108 and slid along the axis of the valve stem 114 into the interlocking gap 500 previously occupied by the valve stem clamp 104 until the seal cartridge 100 clears the valve stem 114, as shown in Figure 5B. Finally, the seal cartridge 100 is laterally removed from the valve, as shown in Figure 5C.

[0046] Once the seal cartridge 100 is removed from the valve, it can be easily and quickly refurbished at a suitable facility. In addition, it is possible to provide an identical new or previously refurbished seal cartridge 100 that can be quickly reinstalled on the valve so that the valve continues to operate while the original seal cartridge 100 is being refurbished. As a result, replacement of the packing seal 200 is quick and easy, minimizing valve downtime.

[0047] In some embodiments, the valve stem clamp 104 is longer than the seal cartridge 100, so that removing the valve stem clamp 104 provides a longer interlocking gap 500 over the valve stem 114 than the seal cartridge 100. In the embodiment of Figures 5A-5C, the valve design accommodates linear sliding of the actuator 102 relative to the valve stem 114, and the valve stem clamp 104 is shorter than the seal cartridge 100, and the difference in length in Figures 5B and 5C is compensated for by sliding the actuator 102 upwards, further away from the valve stem 114, thereby providing sufficient space 500 for the seal cartridge 100 to slide over the valve stem 114. In the illustrated embodiment, this can be accomplished, for example, by pressurizing the space 304 in the spring housing 112 below the spring plate 306.

[0048] Thereby, the present invention allows for removal of the packing seal 200 from the valve without removing the actuator 102. Furthermore, replacement of the seal cartridge 100 does not require disassembly of the bonnet 108 from the valve body 108 and therefore does not require replacement of a larger bonnet gasket, which is typically more expensive than the small gasket that seals the seal cartridge 100 to the bonnet 108. Thus, the present invention allows for quicker replacement of the seal packing material, since the packing material is pre-installed in the seal cartridge 100 before the seal cartridge 100 is installed in the valve. This reduces the possibility of improper packing placement, in cases where the packing configuration is complex. Thereby, the present invention reduces maintenance costs, since replacement of the packing is quick and the seal cartridge 100 is less expensive than the bonnet 108. It is also noted that in the present invention, the packing holes, i.e., the outer holes surrounding the packing 200, are in the seal cartridge 100 and not in the bonnet 108. Thus, if the packing hole is damaged, only the seal cartridge 100 needs to be replaced rather than having to replace the more expensive bonnet 108 .

[0049] The above-described method is illustrated by the flow diagram of FIG. 6 , which includes removing 600 the valve stem clamp 104 from the valve, thereby leaving an unobstructed coupling gap 500 between the valve stem and the actuator, unscrewing 602 the seal cartridge 100 from the bonnet 108, sliding 604 the seal cartridge 100 into the coupling gap 500 along the valve stem 114, removing 606 the seal cartridge 100 from the valve, reinstalling 608 the refurbished seal cartridge 100 on the valve, and reinstalling 610 the valve stem clamp on the valve, where the seal cartridge 100 reinstalled on the valve may be the same one that was removed following its refurbishment, or a separate replacement new or previously refurbished seal cartridge.

[0050] 7 is a cross-sectional view of the bonnet area of ​​an alternative embodiment of the present invention. According to this embodiment, when the seal cartridge 100 is installed in a valve, the seal cartridge 100 extends into the bonnet 108 and is attached to the bonnet 108 by its upper flange 700. The embodiment further includes a "threaded" packing follower 702.

[0051] It should be noted that while the exemplary embodiments shown herein actuate via linear displacement of the valve stem, the present invention can be readily adapted by one of ordinary skill in the art to valves that actuate via rotation of a valve plug within a valve seat, for example, valves in which both the valve plug and valve seat are penetrated by lateral passages that may be brought into alignment or misaligned by rotation of the valve plug.

[0052] It should be further noted that use of the term "valve stem clamp" herein does not necessarily require that the connection between the actuator and the valve stem function as a clamp -- it is only necessary that the valve stem clamp provide physical communication between the valve stem and the actuator, and that the valve stem clamp can be easily removed without significant disassembly of the valve.

[0053] It should also be understood that the present invention is not limited to packing seals, but is applicable to the retrofit of any type of seal in a valve, so long as the seal is capable of sliding along the valve stem.

[0054] The foregoing description of embodiments of the invention has been presented for purposes of illustration and description. Every page of this submission, and all of its contents, however characterized, identified, or numbered, regardless of format or location within the application, is considered a substantial part of this application for all purposes. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of this disclosure.

[0055] Although the present application is presented in a limited number of forms, the scope of the present invention is not limited to these forms only, and various changes and modifications are possible. The disclosure presented herein does not explicitly disclose all possible combinations of features that fall within the scope of the present invention. The features disclosed herein with respect to various embodiments can generally be interchanged and combined in any combination that is not self-contradictory without departing from the scope of the present invention. In particular, the limitations presented in the following dependent claims can be combined with their corresponding independent claims in any number and in any order without departing from the scope of the present disclosure, unless the dependent claims are logically incompatible with each other.

Claims

1. A valve, a valve seat within the valve body; a valve plug configured to control flow of a process fluid through the valve body according to a separation between the valve plug and the valve seat and / or according to a rotational position of the valve plug within the valve seat; a valve stem in mechanical communication with the valve plug; An actuator; a removable valve stem linkage providing a mechanical connection between the actuator and the valve stem such that rotational and / or linear displacement of the actuator is transmitted to the valve stem; a seal cartridge comprising: a cartridge housing removably attached to the valve body; and at least one seal surrounding the valve stem and forming a seal between the cartridge housing and the valve stem while allowing at least one of linear and rotational movement of the valve stem relative to the seal cartridge; Equipped with when the removable valve stem linkage is removed, an unobstructed coupling gap is provided between the actuator and the valve stem; When the cartridge housing is removed from the valve body, the seal cartridge can be slid along the valve stem into the interlocking gap until the seal cartridge no longer surrounds the valve stem and can be laterally removed from the valve. valve.

2. 2. The valve of claim 1, The valve is a rotary valve.

3. 2. The valve of claim 1, The valve is a linear valve.

4. 2. The valve of claim 1, A valve, wherein at least one of the seals is a packing seal.

5. 2. The valve of claim 1, A valve, wherein the removable valve stem linkage functions as a clamp that clamps a lower portion of the actuator at an upper portion of the removable valve stem linkage and clamps an upper portion of the valve stem at a lower portion of the removable valve stem linkage.

6. 2. The valve of claim 1, A valve, wherein lateral access to the removable valve stem linkage does not require removal of any components of the valve.

7. A valve according to any one of claims 1 to 5, A valve, wherein lateral access to said valve requires at most removal of a valve cover, said removal not requiring other disassembly of said valve.

8. 2. The valve of claim 1, The seal cartridge includes: Valve stem guide, Spacer, Grand Follower, Gland flange, and Live Load Spring The valve further comprises at least one of:

9. 2. The valve of claim 1, A valve, wherein a length of the removable valve stem linkage is sufficient to allow removal of the removable valve stem linkage to remove the seal cartridge from the valve.

10. 2. The valve of claim 1, The valve allows linear movement of the actuator, and a combination of removing the removable valve stem linkage and linearly displacing the actuator from the valve stem is sufficient to allow removal of the seal cartridge from the valve.

11. 2. The valve of claim 1, A valve, the bottom of the seal cartridge being secured to a top of the bonnet such that the seal cartridge extends over the bonnet of the cartridge housing.

12. 2. The valve of claim 1, An upper flange of the top of the seal cartridge is attached to the top of the bonnet of a front cartridge housing such that the seal cartridge extends into the bonnet of the valve.

13. 1. A method of refurbishing at least one valve stem seal contained within a valve, comprising: Providing the valve according to claim 1, removing the removable valve stem linkage; Remove the seal cartridge from the valve body; sliding the seal cartridge along the valve stem until the seal cartridge no longer surrounds the valve stem; Laterally remove the seal cartridge from the valve; refurbishing the at least one seal included in the seal cartridge. A method comprising:

14. 14. The method of claim 13 further comprising: translating the actuator away from the valve stem, thereby increasing the coupling gap.

15. 14. The method of claim 13 further comprising: refurbishing the at least one seal included in the seal cartridge.

16. 16. The method of claim 15 further comprising: After refurbishing the seal cartridge, the method comprises reinstalling the seal cartridge on the valve and then reinstalling the removable valve stem linkage on the valve.

17. 14. The method of claim 13 further comprising: A replacement seal cartridge is provided. removing the seal cartridge from the valve and then installing the replacement seal cartridge in the valve; Reinstalling the removable valve stem linkage on the valve. A method comprising:

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