Reversible backup rings for seals

Abstract

A sealing arrangement with one or more backup rings having similar axial faces and geometry to engage a seal, thereby providing a sealing arrangement with reversible and self-retained backup rings. The backup rings may have one or more splits for installation.

Description

REVERSIBLE BACKUP RINGS FOR SEALSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional App. Ser. No. 63 / 602,934, filed on Nov. 27, 2023, which is incorporated herein by reference.TECHNICAL FIELD

[0002] The present disclosure relates to backup rings used with sealing components to seal a gap or junction between parts in an assembly.BACKGROUND

[0003] The use of backup rings is common in the broad field of seals used in industry. A backup ring is typically a ring of harder material used in conjunction with a seal ring of a relatively softer material to support the seal in applications which may be difficult for soft seal materials alone. For example, a rigid plastic backup ring may be used conjunction with an elastomeric rubber seal to provide an assembly in which the seal can effectively seal a gap with greater differential pressure than the softer seal material could withstand without damage. Such rigid backup ring materials may be split to accommodate installation into a component because they are difficult to bend or stretch into a seal housing groove.

[0004] Backup rings typically used in industry may be asymmetrical in design, which necessitates assembling them in the proper orientation with respect to the seal. Assembling the backup ring with the wrong side facing the seal can cause performance problems well known in the art, such as damage to the sealing assembly and leakage.

[0005] Another challenge with typical backup rings comes when assembling components together when a split backup ring is incorporated in the assembly. If the backup ring is bent or not fully inserted into a component groove, it can interfere with another component during assembly or use, causing damage to the backup ring itself, the seals, or other components.

[0006] Therefore, despite attempts in the prior art, there remains a need for a backup ring for a seal that cannot be installed backwards, and that remains fully installed in the groove with the seal.SUMMARY OF EXAMPLE EMBODIMENTS

[0007] In some embodiments, a backup ring comprises a first side and a second side, each side comprising substantially the same profile such that the interface between the backup ring and a seal is the same regardless of which side is facing the seal after installation.

[0008] In some embodiments, a backup ring comprises a first side and a second side, wherein each side comprises a groove along the circumference of each side (i.e., axial face), each channel configured to engage features of a seal to thereby prevent the backup ring from moving radially out of alignment in the sealing assembly.

[0009] In some embodiments, a backup ring comprises a first portion and a second portion, wherein the first portion is narrower than the second portion such that the second portion extends axially farther than the first portion.

[0010] In some embodiments, the backup ring may be split in one or more locations to allow installation and to accommodate diameter tolerances in the assembly. The one or more splits may be angled or of a shape or configuration allowing at least a partial overlap of the ends.

[0011] In some embodiments, one or more backup rings may have a groove or other concave recesses on both sides, or may have a narrower portion and a wider portion, to interface witha protruding portion of at least one seal component, thereby preventing radial movement out of alignment, and may also have one or more splits for installation. Thus, the one or more backup rings are self-retaining and reversible.BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Fig. l is a perspective view of a backup ring;

[0013] Fig. 2 is a cross-section view of a backup ring;

[0014] Fig. 3 is an enlarged, detailed view of area 3 of Fig. 2;

[0015] Fig. 4 is a detailed, partial view of a cross-section of an assembly with a seal and reversible backup rings;

[0016] Fig. 5 is a detailed, partial view of a cross-section of an assembly with a seal and reversible backup rings;

[0017] Fig. 6 is a detailed, partial view of a cross-section of an assembly with a seal and reversible backup rings;

[0018] Fig. 7 is a detailed, partial view of a cross-section of an assembly with a seal a reversible backup ring;

[0019] Fig. 8 is a detailed, partial view of a cross-section of an assembly with a seal and reversible backup rings;

[0020] Fig. 9 is a perspective view of a reversible backup ring; and

[0021] Fig. 10 is a detailed, partial view of a cross-section of a backup ring of a seal assembly.DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

[0022] The following descriptions depict only example embodiments and are not to be considered limiting in scope. Any reference herein to “the invention” is not intended torestrict or limit the invention to exact features or steps of any one or more of the exemplary embodiments disclosed in the present specification. References to “one embodiment,” “an embodiment,” “various embodiments,” and the like, may indicate that the embodiment s) so described may include a particular feature, structure, or characteristic, but not every embodiment necessarily includes the particular feature, structure, or characteristic. Further, repeated use of the phrase “in one embodiment,” or “in an embodiment,” do not necessarily refer to the same embodiment, although they may.

[0023] Reference to the drawings is done throughout the disclosure using various numbers. The numbers used are for the convenience of the drafter only and the absence of numbers in an apparent sequence should not be considered limiting and does not imply that additional parts of that particular embodiment exist. Numbering patterns from one embodiment to the other need not imply that each embodiment has similar parts, although it may.

[0024] Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention, which is to be given the full breadth of the appended claims and any and all equivalents thereof. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. Unless otherwise expressly defined herein, such terms are intended to be given their broad, ordinary, and customary meaning not inconsistent with that applicable in the relevant industry and without restriction to any specific embodiment hereinafter described. As used herein, the article “a” is intended to include one or more items. When used herein to join a list of items, the term “or” denotes at least one of the items, but does not exclude a plurality of items of the list. For exemplary methods or processes, the sequence and / or arrangement of steps described herein are illustrative and not restrictive.

[0025] It should be understood that the steps of any such processes or methods are not limited to being carried out in any particular sequence, arrangement, or with any particulargraphics or interface. Indeed, the steps of the disclosed processes or methods generally may be carried out in various sequences and arrangements while still falling within the scope of the present invention.

[0026] The term “coupled” may mean that two or more elements are in direct physical contact. However, “coupled” may also mean that two or more elements are not in direct contact with each other, but yet still cooperate or interact with each other.

[0027] The terms “comprising,” “including,” “having,” and the like, as used with respect to embodiments, are synonymous, and are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including, but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes, but is not limited to,” etc.).

[0028] As previously discussed, there is a need for a backup ring for a seal assembly which is self-retaining and reversibly installable.

[0029] In some embodiments, as shown in Fig. 1, a backup ring 100 has a split 102 to allow assembly into a groove of a sealing arrangement. The split 102, as shown, may be angled to allow a first end 104 to overlap a second end 106 so as to ensure there are no gaps in the backup ring 100 when installed in the sealing arrangement. It will be appreciated by one skilled in the art that myriad types of splits with various angles, orientations, and shapes may be used with backup rings in sealing arrangements. Accordingly, such changes in the split are specifically contemplated herein.

[0030] Fig. 2 illustrates a sectional view of the backup ring 100, with Fig. 3 showing an enlarged area along the circle 3 of Fig. 2. As best shown in Fig. 3, the backup ring 100 is preferably radially taller than its axial width. A first radial edge 108 (e.g., outer diameter) is relatively flat and configured to interface with assembly components, while a second radial edge 110 (e.g., inner diameter) is relatively convex or pointed to aid in insertion into thesealing arrangement, as will be discussed later herein. A first axial side 112 comprises a first channel 114, and a second axial side 116 comprises a second channel 118, each channel 114, 118 running the circumference of the backup ring 100 and complementary in size and shape. As a result of the mirrored axial sides 112, 116, the backup ring 100 may be installed in a sealing assembly regardless of orientation. In other words, in one orientation, channel 114 may engage a protrusion of the seal, but if placed in reversed orientation, channel 118 may engage the protrusion of the seal, thereby providing a backup ring which is reversible and self-retaining radially with the seal.

[0031] The size and location of the channels 114, 118, as well as the material properties of the backup ring 100 may be adjusted for use in various applications. For example, in some embodiments, the axially narrower portion 120 (located between both channels 114, 118) of the backup ring 100 may be no less than half of the axial width of the backup ring 100. In some embodiments, the radial width of the channels 114, 118 may be in a range of 1.25 to four times the depth of the channels 114, 118. The channels 114, 118 may be of any internal shape, but internal radii are preferred to reduce stress concentration that may occur at sharp points. In some embodiments, the backup ring 100 comprises rigid polymers and the channels 114, 118 have a width of three times their depth and internal radii no less than 0.5 times the channel depth.

[0032] It will be appreciated that any number of configurations of the present disclosure are possible, and that the backup ring 100 can be utilized for many shapes, sizes, configurations and applications. One application where such a backup ring may be particularly useful is a seal with a T-shaped section and two backup rings, commonly referred to as a T-seal. For example, a typical T-seal sealing arrangement of the prior art has a seal and two backup rings that are placed in a groove of a first assembly component and engage second assembly component to seal the gap therebetween. The seal material is typically a softer, elastomericmaterial chosen for sealing performance and the backup rings are typically a harder material selected to support the softer seal to prevent it being damaged by pressure or relative motion between the assembly components.

[0033] Many backup ring designs have a radiused or chamfered comer engaging the seal to avoid damage to the softer seal material. Other types of backup rings in the prior art may have interlocking retention features on the side interfacing with the seal to keep the backup rings in the groove and radially aligned to the seal. Backup rings without interlocking retention features can be difficult to keep radially aligned with the seal and may be partially protruding out of the groove of first assembly component prior to assembly with second assembly component. Then when the two assembly components are assembled together, the protruding portion of a backup ring can be pinched and rolled out of the groove or sheared off by opposing edges of the groove and assembly component. Backup rings typical in the prior art with features on only one side, such as a radiused or chamfered comer, or interlocking retention features, may be installed incorrectly, reversed in orientation with such features facing away from the seal, resulting in problems well known in the art, such as installation damage, damage from pressure or motion, damage to the seal by sharp backup ring edges, leakage, and loss of pressure.

[0034] To overcome these and other limitations in the prior art, Fig. 4 shows a partial cross- sectional view of an embodiment of the present disclosure with a sealing arrangement 122 with a T-shaped section seal 124 and two reversible, self-retaining backup rings 100A, 100B placed in a groove 126 of first assembly component 128 and engaging second assembly component 130 to seal the gap therebetween. The seal 124 material may be a softer, elastomeric material (for example, rubber or polyurethane) chosen for sealing performance and the backup rings 100 A, 100B may be a harder material (for example, rigid flexible polymers, such as polyamide, polyetheretherketone, or polyacetal) selected to support thesofter seal 124 to prevent the softer seal 124 being damaged by pressure or relative motion between the assembly components 128, 130 by blocking the gaps 132, 134 therebetween. A first protrusion 136 on a first side of the seal 124 mates with the second channel 118 in the backup ring 100 A, and a second protrusion 138 of the seal 124 mates with the first channel 114 of the backup ring 100B. If either backup ring 100 A, 100B were installed in the reversed orientation to the seal 124, the interfacing profile would remain the same. Thus, mistakes during installation may be prevented and problems such as damage and leakage may be avoided.

[0035] Additionally, because the seal 124 is a continuous annulus, the seal 124 is retained in the groove 126 via its hoop strength. Because the protrusions 136, 138 of the seal 124 mate with the respective channels 114, 118, each backup ring 100A, 100B is secured in position (e.g., snap-fitted) in relation to the seal 124, which prevents the backup ring 100 A, 100B from exiting the groove 126 prior to assembly with a second assembly component 130 and being subject to rolling or shearing during assembly, further overcoming damage and leakage experienced in the prior art.

[0036] In some embodiments, as shown in Fig. 5, a four-piece seal arrangement 140 comprises a first seal component 142 and a second seal component 144, the second seal component 144 comprising a first protrusion 146 to mate with the second channel 118 of the first backup ring 100 A and a second protrusion 148 to mate with the first channel 114 of second backup ring 100B. Together the first seal component 142 and second seal component 144 seal the junction between first assembly component 128 and second assembly component 130. As in prior embodiments, if either backup ring 100A, 100B were installed in the reversed orientation to the seals 142, 144, the interfacing profile would remain the same, with the backup rings 100A, 100B secured in place during installation. Thus, mistakes during installation may be prevented and problems such as damage and leakage may be avoided.

[0037] In some embodiments, as shown in Fig. 6, a four-piece seal arrangement 150 comprises a first seal component 152 and a second seal component 154 which seal the junction between first assembly component 128 and second assembly component 130. The first seal component 152 comprises a first protrusion 156 to mate with the second channel 118 of the first backup ring 100 A and a second protrusion 158 to engage the first channel 114 of second backup ring 100B. Together the first seal component 152 and second seal component 154 seal the junction between first assembly component 128 and second assembly component 130. As in prior embodiments, if either backup ring 100A, 100B were installed in the reversed orientation to the seals 152, 154, the interfacing profile would remain the same, with the backup rings 100A, 100B secured in place during installation. Thus, mistakes during installation may be prevented and problems such as damage and leakage may be avoided.

[0038] In some embodiments, as shown in Fig. 7, an asymmetrical sealing arrangement 160 comprises a seal 162 configured to seal pressure or media in one direction in the junction between first assembly component 128 and second assembly component 130, and one selfretained reversible backup ring 100. In other words, the seal 162 comprises a protrusion 164 for mating with second channel 118 of backup ring 100. As in prior embodiments, if the backup ring 100 was installed in the reversed orientation to the seal 162, the interfacing profile would remain the same, with the backup ring 100 secured in place during installation. Thus, mistakes during installation may be prevented and problems such as damage and leakage may be avoided.

[0039] In yet another embodiment, as shown in Fig. 8, a three-piece seal arrangement 166 comprises a seal 168 to seal the junction between first assembly component 128 and second assembly component 130. A first protrusion 170 on a first side of the seal 168 mates with the second channel 118 in the backup ring 100 A, and a second protrusion 172 of the seal 168 mates with the first channel 114 of the second backup ring 100B. As shown, the backup rings100A, 100B may extend the full radial depth of the first component groove 174. If either backup ring 100 A, 100B were installed in the reversed orientation to the seal 168, the interfacing profile would remain the same. Thus, mistakes during installation may be prevented and problems such as damage and leakage may be avoided.

[0040] Referring to Fig. 9, in some embodiments, a self-retained reversible backup ring 200 may comprise a plurality of splits 202A-C which form a plurality of ring segments 204A-C. As in prior embodiments, the backup ring 200 comprises channels on each axial face that are configured to mate with protrusions of a seal. As a result, the backup ring 200 need not be a continuous piece, but may be segmented, as shown, with each segment 204A-C secured in position due to the mating of the protrusion and channel, as described earlier herein. In this embodiment, the segments 204A-C may be identical and each may be installed in reversed orientation without changing the assembled form.

[0041] While the backup rings 100, 200 disclosed above are shown and described with channels 114, 118, it will be appreciated that channels are not required and that other configurations that provide for a “locking” mechanism may be used without departing herefrom. For example, referring to Fig. 10, a backup ring 300 may comprise a first portion 302 and a second portion 304, wherein the first portion 302 is narrower in width than the second portion 304 such that the second portion 304 extends axially farther than the first portion 302. A contour or notch 306, 308 is formed at the transition from the narrower first portion 302 to the wider second portion 304. This notch 306, 308 functions to secure the backup ring 300 in the sealing assembly. In other words, the second portion 304 is “locked” or secured under the protrusion (e.g., 136, 138) of the seal (e.g., 124) in the groove (e.g. 126) of the sealing assembly (e.g., 122). As in other embodiments, because each axial face 310, 312 is a mirror image of the other, the backup ring 300 may be installed in either direction, and on either side of a seal, without being installed incorrectly, overcoming limitations in theprior art. Accordingly, it is contemplated herein that a backup ring 100, 200, 300 comprises axial faces that are a mirror image of one another, and that each axial face comprises a securement mechanism, wherein the securement mechanism is a channel, notch, or other contour sufficient to interlock with a protrusion of a seal in a sealing assembly.

[0042] Accordingly, it will be appreciated from the foregoing that the backup rings 100, 200 disclosed herein solve the need for a backup ring for a seal that cannot be installed backwards, and that remains fully installed in the groove with the seal.

[0043] Although exemplary embodiments above show sealing arrangements in a groove around a first assembly component radially inside the second assembly component, in a configuration known as a piston-style arrangement, it will be appreciated that in other embodiments, the seal arrangement may be inverted for a configuration known as a rod-style arrangement, with the seal in a groove inside the radially outer assembly component and surrounding the radially inner component.

[0044] The term “groove” used above refers to the housing for the seal. This is typically a simple rectangular groove formed in a cylindrical surface, but the housing may comprise multiple components, or various shapes without departing from the present invention.

[0045] The term “rings” used to describe seals or backups, as in backup rings, does not restrict the disclosed invention to round or circular shapes. The term “backup ring” is common because seals with backups are most commonly used with cylindrical parts. However, seals with such reversible, self-retaining backups may also be used to seal nonround assembly components with various perimeter shapes.

[0046] It will be appreciated that systems and methods according to certain embodiments of the present disclosure may include, incorporate, or otherwise comprise properties or features (e.g., components, members, elements, parts, and / or portions) described in other embodiments. Accordingly, the various features of certain embodiments can be compatiblewith, combined with, included in, and / or incorporated into other embodiments of the present disclosure. Thus, disclosure of certain features relative to a specific embodiment of the present disclosure should not be construed as limiting application or inclusion of said features to the specific embodiment unless so stated. Rather, it will be appreciated that other embodiments can also include said features, members, elements, parts, and / or portions without necessarily departing from the scope of the present disclosure.

[0047] Moreover, unless a feature is described as requiring another feature in combination therewith, any feature herein may be combined with any other feature of a same or different embodiment disclosed herein. Furthermore, various well-known aspects of illustrative systems, methods, apparatus, and the like are not described herein in particular detail in order to avoid obscuring aspects of the example embodiments. Such aspects are, however, also contemplated herein.

[0048] Exemplary embodiments are described above. No element, act, or instruction used in this description should be construed as important, necessary, critical, or essential unless explicitly described as such. Although only a few of the exemplary embodiments have been described in detail herein, those skilled in the art will readily appreciate that many modifications are possible in these exemplary embodiments without materially departing from the novel teachings and advantages herein. Accordingly, all such modifications are intended to be included within the scope of this invention.

Claims

CLAIMSWhat is claimed is:

1. A sealing assembly, comprising: a backup ring, comprising: at least one split forming a first end and a second end; the first end partially overlapping the second end; a first axial side comprising a first securement mechanism; and a second axial side comprising a second securement mechanism; wherein the first and second axial sides are mirror images of one another.

2. The sealing assembly of claim 1, further comprising at least one seal comprising at least one protrusion configured to mate or abut the first securement mechanism or second securement mechanism of the backup ring.

3. The sealing assembly of claim 2, comprising: a first assembly component comprising a groove, wherein the at least one seal is configured to be seated within the groove and partially extend outside the groove to abut a second assembly component; wherein when the backup ring is mated or abutting with the at least one seal, the at least one backup ring is retained in position within the groove.

4. The sealing assembly of claim 1, wherein the first securement mechanism is a first channel and the second securement mechanism is a second channel.

5. The sealing assembly of claim 1, wherein the first securement mechanism is a first notch and the second securement mechanism is a second notch.

6. The sealing assembly of claim 1, further comprising a plurality of seals, wherein at least one seal of the plurality of seals comprises at least one protrusion configured to mate with the first or second channel of the backup ring.

7. The sealing assembly of claim 1, further comprising a plurality of splits forming a plurality of segments of the backup ring, each segment comprising a first end and a second end.

8. The sealing assembly of claim 7, comprising: a first assembly component comprising a groove, wherein the at least one seal is configured to be seated within the groove and partially extend outside the groove to abut a second assembly component; wherein each segment of the backup ring is configured to mate with or abut the at least one seal via the first or second securement mechanism to thereby be retained in position within the groove and in relation to the at least one seal.

9. A sealing assembly, comprising: a backup ring, comprising: at least one split forming at least one first end and at least one second end, the at least one first end configured to at least partially overlap the at least one second end, a first axial side comprising a first channel, and a second axial side comprising a second channel; and at least one seal comprising at least one protrusion configured to mate with the first channel or the second channel of the backup ring; wherein when the at least one protrusion of the at least one seal is mated with the first or second channel of the backup ring, the backup ring is retained inposition in relation to the at least one seal within a groove of a first assembly component.

10. The sealing assembly of claim 9, further comprising a plurality of seals, wherein at least one seal of the plurality of seals comprises the at least one protrusion configured to mate with the first or second channel of the backup ring.

11. The sealing assembly of claim 9, further comprising a plurality of splits forming a plurality of segments of the backup ring, each segment comprising a first end and a second end.

12. The sealing assembly of claim 11, comprising: a first assembly component comprising a groove, wherein the at least one seal is configured to be seated within the groove and partially extend outside the groove to abut a second assembly component; wherein each segment of the backup ring is configured to mate with the at least one protrusion of the at least one seal via the first or second channel to thereby be retained in position within the groove and in relation to the at least one seal.

13. A sealing assembly, comprising: a backup ring, comprising: at least one split forming at least one first end and at least one second end, the at least one first end configured to at least partially overlap the at least one second end, a first axial side comprising a first securement mechanism, and a second axial side comprising a second securement mechanism,wherein the first and second axial sides are mirror images of one another; and at least one seal comprising at least one protrusion configured to mate with or abut the first or second securement mechanism of the backup ring; wherein when the at least one protrusion of the at least one seal is mated with or abutting the first or second securement mechanism of the backup ring, the backup ring is retained in position in relation to the at least one seal within a groove of a first assembly component.

14. The sealing assembly of claim 13, wherein the first securement mechanism is a first channel and the second securement mechanism is a second channel.

15. The sealing assembly of claim 13, wherein the first securement mechanism is a first notch and the second securement mechanism is a second notch.

16. The sealing assembly of claim 14, further comprising a plurality of seals, wherein at least one seal of the plurality of seals comprises at least one protrusion configured to mate with the first or second channel of the backup ring.

17. The sealing assembly of claim 13, further comprising a plurality of splits forming a plurality of segments of the backup ring, each segment comprising a first end and a second end.

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