Clamping Arrangement for Valves in Reciprocating Compressor Cylinders

20190285185 ยท 2019-09-19

    Inventors

    Cpc classification

    International classification

    Abstract

    The present disclosure generally relates to a clamping arrangement for a valve assembly (e.g., a suction or discharge valve) of a reciprocating compressor. More specifically, the present disclosure describes a clamping arrangement for clamping a valve assembly to a cylinder. The clamping arrangement may include a valve assembly, a clamping mechanism and a plurality of fasteners for directly securing the valve assembly to a cylinder of the compressor. The clamping mechanism has no direct contact or interaction with a valve cover which seals a valve cage from the surrounding environment. As such, the need for a valve gland is negated. In use, the clamping mechanism may be in the form of a clamping ring or an integrated flange for securing the valve assembly directly to the cylinder by the plurality of fasteners. The clamping arrangement may further include an improved seal located between the valve assembly and the cylinder.

    Claims

    1. A clamping device for securing a suction or discharge valve assembly to a cylinder in a reciprocating compressor, the valve assembly at least partially disposed within a valve cage sealed from the surrounding environment by a valve cover and seal, the clamping device comprising: a clamping mechanism for securing the valve assembly to the cylinder, wherein the clamping mechanism is free of contact with the valve cover.

    2. The clamping device of claim 1, wherein the clamping mechanism includes a clamping ring for securing the suction or discharge valve assembly directly to the cylinder.

    3. The clamping device of claim 2, wherein the clamping ring is configured to extend around, and contact, a perimeter portion of the suction or discharge valve assembly.

    4. The clamping device of claim 2, wherein the clamping ring includes a plurality of openings for receiving a plurality of fasteners for securing the clamping ring, and hence the suction or discharge valve assembly, to the cylinder.

    5. The clamping device of claim 1, wherein the clamping mechanism is integrated with the suction or discharge valve assembly.

    6. The clamping device of claim 5, wherein the clamping mechanism comprises a clamping flange that is integral to the suction or discharge valve assembly, the clamping flange for securing the suction or discharge valve assembly directly to the cylinder.

    7. The clamping device of claim 6, wherein the integrated clamping flange includes a plurality of openings for receiving a plurality of fasteners for securing the integrated clamping flange, and hence the suction or discharge valve assembly, to the cylinder.

    8. The clamping device of claim 4, or 7, wherein the plurality of fasteners are elongated fasteners that extend adjacent to, but do not contact, the valve cover.

    9. The clamping device of any of the preceding claims, further comprising a seal located between the valve assembly and the cylinder, wherein the seal includes a zig-zag or wavy pattern such that a portion of the seal lies adjacent to a perimeter of the valve assembly between fastener openings while a portion of the seal lies interior of the fastener opening.

    10. A method for securing a valve assembly to a cylinder of a reciprocating compressor, the method comprising the steps of: placing the valve assembly into a valve cage; securing the valve assembly to the cylinder via a clamping mechanism having a plurality of openings for receiving a first plurality of fasteners; and securing a valve cover to the valve cage, the valve cover having a second plurality of openings for receiving a plurality of cover fasteners; wherein the clamping mechanism and the first plurality of fasteners have no contact with the valve cover.

    11. The method of claim 10, wherein the clamping mechanism is a clamping ring that extends around a perimeter of the valve assembly.

    12. The method of claim 10, wherein the clamping mechanism is a flange integrated into the valve assembly.

    Description

    BRIEF DESCRIPTION OF THE DRAWINGS

    [0021] By way of example, specific embodiments of the disclosed device will now be described, with reference to the accompanying drawings, in which:

    [0022] FIG. 1 illustrates a side prospective view of an illustrative piston compressor;

    [0023] FIG. 2 illustrates a cross-sectional view of the piston compressor shown in FIG. 1;

    [0024] FIG. 3 illustrates a cross-sectional view of a cylinder used in combination with the piston compressor shown in FIG. 1;

    [0025] FIG. 4A illustrates a cross-sectional perspective view of a conventional discharge valve used in combination with the piston compressor shown in FIG. 1;

    [0026] FIG. 4B illustrates a cross-sectional perspective view of a conventional suction valve used in combination with the piston compressor shown in FIG. 1;

    [0027] FIG. 5 illustrates a cross-sectional perspective view of a prior art clamping arrangement for a valve assembly used in combination with the piston compressor shown in FIG. 1;

    [0028] FIG. 6A illustrates a cross-sectional perspective view of a valve assembly used in reciprocating compressors, the valve assembly being secured to the cylinder by an exemplary external clamping arrangement according to the present disclosure;

    [0029] FIG. 6B illustrates a cross-sectional perspective view of a valve assembly used in reciprocating compressors, the valve assembly being secured to the cylinder by an exemplary integrated clamping arrangement according to the present disclosure;

    [0030] FIG. 6C illustrates an alternate cross-sectional perspective view of a valve assembly used in reciprocating compressors, the valve assembly being secured to the cylinder by the exemplary integrated clamping arrangement shown in FIG. 6B, the integrated clamping arrangement including elongated fasteners;

    [0031] FIG. 7 illustrates a cross-sectional perspective view of a valve assembly located within a cylinder, the valve assembly being secured to the cylinder by the exemplary integrated clamping arrangement shown in FIG. 6B;

    [0032] FIG. 8A is a perspective view of a valve assembly, the valve assembly including the exemplary integrated clamping arrangement shown in FIG. 6B, the integrated clamping arrangement including an exemplary embodiment of a seal; and

    [0033] FIG. 8B is a bottom view of the valve assembly shown in FIG. 8A, the valve assembly including the exemplary integrated clamping arrangement shown in FIG. 6B and the exemplary embodiment of the seal.

    DETAILED DESCRIPTION

    [0034] A device and method in accordance with the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the device and method are shown. The disclosed device and method, however, may be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the device and method to those skilled in the art. In the drawings, like numbers refer to like elements throughout.

    [0035] The present disclosure describes a clamping arrangement for a valve assembly used in reciprocating compressors. More specifically, the present disclosure describes a clamping arrangement for a valve assembly used in, for example, a compressor cylinder. Referring to FIGS. 6A-6C, the clamping arrangement 100, 200 may include a valve assembly 50, a clamping mechanism 120, 220 and a plurality of fasteners 130 for directly securing the valve assembly 50 to the cylinder 12. As will be described in greater detail below, in use, the plurality of fasteners 130 may directly secure the valve assembly 50 to the cylinder 12. As best seen in FIG. 6C, the improved clamping arrangement 200 may also include a valve cover 56 for covering and sealing the valve cage 40. Although, improved clamping arrangement 200 is shown, the same may apply to clamping arrangement 100. As previously mentioned, the valve assembly 50 may be a discharge valve 60 or a suction valve 70, although it is contemplated that the disclosed clamping arrangement can be used in combination with other types of valve assemblies. In addition, although the present disclosure illustrates and discusses use of the clamping arrangement for a valve assembly in connection with compressors and, more specifically, piston compressors, it is contemplated that the improved clamping methods may be used in connection with any valve or valve assembly in any other appropriate application.

    [0036] The present disclosure achieves the desired results by incorporating a separate clamping mechanism 120, 220 that has no contact or direct interaction with the valve cover 56. As such, the valve gland 54 (FIG. 5) is eliminated. Referring to FIG. 6A, the clamping arrangement 100 incorporates a separate clamping mechanism 120, which in the illustrated embodiment is a clamping ring 122, to provide the required hold down force for the valve assembly 50. As noted, the separate clamping mechanism 120 may be in the form of a clamping ring 122 that extends around the perimeter of the valve assembly 50. The clamping ring 122 may include a plurality of openings for receiving a plurality of fasteners 130 for securing the clamping ring 122 and hence the valve assembly 50 to the cylinder 12. The valve assembly 50 and, more specifically, the valve seat 61, 72 and/or the valve guard 62, 71 (depending on the type of valve assembly) may include a circumferential lip 116 that is received on an upper surface 13 of the compressor cylinder 12. In use, the clamping ring 122 may contact the upper surface of the valve assembly 50, more specifically, the circumferential lip 116 of the valve seat 61, 72 and/or the valve guard 62, 71, so that when the fasteners 130 are tightened, the clamping ring 122 provides a clamping force against the lip 116 to clamp the lip 116 and the valve assembly 50 against the cylinder 12. In use, as previously mentioned, the clamping ring 122 is free from any contact or other direct interaction with the valve cover 56.

    [0037] Alternatively, referring to FIGS. 6B, 6C and 7, the clamping arrangement 200 may include an integrated clamping mechanism 220. The integrated clamping mechanism 220 may include a valve assembly 50 having an integrated clamping flange 222. The integrated clamping flange 222 may be configured to receive fasteners 130 to provide the required hold down force for the valve assembly 50. As shown, the integrated clamping flange 222 may be integral to the valve assembly 50. The integrated clamping flange 222 may include a plurality of openings for receiving a plurality of fasteners 130 for securing the integrated clamping flange 222 and hence the valve assembly 50 to the cylinder 12. The integrated clamping flange 222 may include a circumferential lip that is received on an upper surface 13 of the compressor cylinder 12. Thus arranged, when the fasteners 130 are tightened, the integrated clamping flange 222 is clamped against the cylinder 12, thus securing the valve assembly 50 in place with respect to the cylinder 12. Alternatively, the integrated clamping flange 222 may feature a lip for only a part of the total circumference. In use, as previously mentioned, the integrated clamping flange 222 is free from any contact or other interaction with the valve cover 56.

    [0038] In this manner, a new improved clamping method for valve assemblies is disclosed, which is independent of any clamping force provided by or guided through the valve cover 56, but instead utilizes a separate clamping ring 122 or an integrated clamping flange 222 including a plurality of openings spaced about the perimeter of the valve assembly 50 to provide a desired hold down force. The clamping ring 122 or an integrated clamping flange 222 is, in the illustrated embodiments, completely free from any physical contact with the valve cover 56.

    [0039] In use, the clamping ring 122 or integrated clamping flange 222 may be secured to the cylinder 12 by a plurality of fasteners 130. The fasteners 130 can be any fasteners now known or hereafter developed including, but not limited to, studs/bolts and nuts (as generally shown), screws, etc. Moreover, referring to FIG. 6C, the plurality of fasteners 130 may be extended or elongated fasteners, such as elongated bolts, that extend adjacent to, but do not contact or otherwise interact with the valve cover 56. By incorporating elongated fasteners 130 as shown, a desired pre-tensioning may be achieved while minimizing the effects of strain loss over time from thermal effects or relaxation. It should be understood that while elongated fasteners have been shown and described in connection with the clamping arrangement 200, such elongated fasteners may also be used in connection with the clamping arrangement 100 described in relation to FIG. 6A.

    [0040] In use, the fasteners 130 may supply a desired hold down force to secure the valve assembly 50 to the cylinder 12. In the illustrated embodiments, the fasteners 130 may be positioned in a circular pattern around the perimeter of the valve assembly 50 within the gas filled passage area of the cylinder 12. As mentioned, the fasteners 130 are also free from any physical contact or engagement with the valve cover 56.

    [0041] In this manner, the hold down force applied to the valve assembly 50 may be directly applied by a separate clamping mechanism 120 associated with the outer perimeter of the valve assembly 50 to secure the valve assembly 50 directly to the cylinder 12. Alternatively, the hold down force applied to the valve assembly 50 may be directly applied by an extended, integrated circumferential flange 222 having a circular hole pattern, through which the aforementioned hold down fasteners 130 extend and on which a plurality of nuts (or bolt heads) may press down. This extended circumferential flange 222 may be an integral part of the valve assembly 50.

    [0042] According to the present disclosure, the improved clamping arrangement 100, 200 eliminates the clamping function of the valve cover 56, and instead directly applies a clamping arrangement to the valve assembly 50. As previously noted, the improved clamping arrangement may require less precise dimensional tolerances of parts, easier assembly, increased reliability of the different seals, minimizes the required space and thus can produce a smaller and lighter cylinder.

    [0043] One or more sealing elements may be disposed between the valve assembly 50 and the cylinder 12, more specifically, surface 13 formed on the cylinder 12. The seal may be any conventional seal now known or hereafter developed. For example, the seal may be a conventional circular seal that sits between the cylinder 12 and the bottom surface of the valve assembly adjacent to the perimeter of the valve assembly. Referring to FIGS. 8A and 8B illustrating the clamping arrangement 200, the seal 250 may include a zig-zag or wavy pattern. As shown, a portion 251 of the seal 250 lies adjacent to a perimeter 225 of the integrated flange 222 between fastener openings 140 but at each fastener opening 140, a portion 252 of the seal 250 lies interior (e.g., inwards away from the perimeter) of the fastener opening 140. As such, the seal 250 provides a greater sealing area than a simple circular seal. The seal 250 is also better able to handle the non-uniform surface pressure distribution associated with the clamping arrangement 250 (the surface pressure is non-uniformly distributed due to the effects of the circumferentially distributed location of the fasteners in combination with the actual stiffness of the integrated clamping flange). It should be understood that while the seal 250 has been shown and described in connection with the clamping arrangement 200, the seal 250 may also be used in connection with the clamping arrangement 100. In use, by providing a seal 250 with a zig-zag or wavy pattern, the bending of the valve seat and guard may be reduced, which improves the sealing capabilities of the valve assembly. The seal 250 may be made from any known material including, but not limited, to a metallic or non-metallic material. In addition, the seal 250 may be made from a combination of materials.

    [0044] As used herein, an element or step recited in the singular and proceeded with the word a or an should be understood as not excluding plural elements or steps, unless such exclusion is explicitly recited. Furthermore, references to one embodiment of the present invention are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.

    [0045] While certain embodiments of the disclosure have been described herein, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.