Plug valve

Abstract

The plug valve comprises a valve body, a valve element assembly and a valve rod, an antifriction part is additionally arranged between a first surface of a rotating foot of the valve rod and a second surface of an end cover, and the first surface rotates relative to the second surface through friction of the antifriction part, namely, the end cover is in non-direct face-to-face friction contact with the rotating foot of the valve rod. Therefore, the machining precision of the end cover and the valve rod can be reduced, the machining cost can be reduced, the friction reducing part can be made of materials with relatively small friction resistance, friction force can be reduced, then the rotating torque is reduced, the clamping feeling of valve rod rotating is reduced, and the valve rod rotating smoothness is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of gas control, in particular to a plug valve. Background Art

[0002] A plug valve is a valve whose working principle is a rotary valve in the shape of a closing piece or a plunger. The channel opening on the valve plug is connected or separated with the channel opening on the valve body by the rotation angle to realize the action of opening or closing the channel.

[0003] The plug valve includes a valve body, a valve stem, an end cover, a valve core and a switch knob. When working, the user rotates the switch knob by hand, so that the valve stem drives the valve core to rotate, thereby controlling the flow rate. During the rotation process, under the reverse thrust of the spring, the upper end face of the valve stem rotation angle and the bottom face of the end cover always keep close to each other and rotate frictionally, which is prone to large friction and not smooth rotation.

[0004] How to provide a plug valve that rotates smoothly is a technical problem that needs to be solved urgently by technicians in this field. Utility Model Content

[0005] The utility model provides a plug valve which can improve the smoothness of valve stem rotation.

[0006] The utility model provides a plug valve, comprising a valve body, a valve core assembly and a valve stem, wherein the valve body is further provided with an end cover, the plug valve is provided with a valve cavity, the valve core assembly is located inside the valve cavity, the first end portion of the valve stem passes through the end cover and is at least partially located inside the valve cavity, the valve stem has a rotating foot, and the rotating foot and the valve core assembly are circumferentially limited; the rotating foot and the end cover respectively have a first surface and a second surface arranged opposite to each other in the axial direction, a friction reducing portion is provided between the first surface and the second surface, and the first surface can rotate relative to the second surface through friction of the friction reducing portion.

[0007] The utility model provides a plug valve, in which a friction reducing portion is added between a first surface and a second surface. The first surface can rotate relative to the second surface through friction of the friction reducing portion, thereby reducing the friction between the valve stem and the end cover, thereby reducing the rotational torque, reducing the sticking feeling of the valve stem when rotating, and improving the smoothness of the valve stem rotation. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a schematic diagram of the structure of a plug valve in one embodiment of the utility model;

[0009] Figure 2 for Figure 1 A partial cross-sectional structural schematic diagram of the plug valve shown;

[0010] Figure 3 for Figure 2 I is a partial enlarged view of the structure shown;

[0011] Figure 4 for Figure 1 The schematic diagram of the structure of the valve stem in the plug valve shown;

[0012] Figure 5 for Figure 1 The schematic diagram of the structure of the end cover of the plug valve shown;

[0013] Figure 6 for Figure 1 The structural schematic diagram of the retaining ring shown;

[0014] Figure 7 for Figure 1 A schematic diagram of the structure of a valve sleeve in a valve core assembly shown;

[0015] Figure 8 This is a schematic diagram of the structure of a plug valve in another embodiment of the utility model;

[0016] Fig. 9 for Figure 8 A is a partial enlarged view of the structure shown;

[0017] Fig.10 for Figure 8 Bottom view of the end cap in the structure.

[0018] in, Figures 1 to 7 The one-to-one correspondence between component names and reference numerals is as follows:

[0019] 1 valve body; 2 valve stem; 20 stem; 2a first end; 21 rotating foot; 211 first surface; 201 slot; 3 end cover; 31 second surface; 32 support portion; 33 mounting hole; 4 valve core assembly; 40 valve core sleeve; 4a recessed portion; 41 notch; 5 spring; 6 retaining ring; 7 handle;

[0020] 6' wear resistant coating. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0022] Please refer to Figures 1 to 7 , Figure 1 This is a schematic diagram of the structure of a plug valve of the utility model; Figure 2 for Figure 1 A schematic diagram of a partial cross-sectional structure of the plug valve shown; Figure 3 for Figure 2 I is a partial enlarged view of the structure shown; Figure 4 for Figure 1The schematic diagram of the structure of the valve stem in the plug valve shown; Figure 5 for Figure 1 The schematic diagram of the structure of the end cover of the plug valve shown; Figure 6 for Figure 1 The structural schematic diagram of the retaining ring shown; Figure 7 for Figure 1 Schematic diagram of the structure of the valve sleeve in the valve core assembly shown.

[0023] The utility model provides a plug valve, comprising a valve body 1, a valve stem 2, a valve core component 4 and an end cover 3.

[0024] The valve body 1 has a first port and a second port on the outside, the valve body 1 and the end cover 3 form a valve cavity 13, the end cover 3 has a support portion 32, the support portion 32 is supported on the upper part of the valve body 1, and a mounting hole 33 can be provided on the support portion 32 for installing bolts and other connectors to be fixedly connected with the valve body. The valve core assembly 4 is located inside the valve cavity 13, the valve stem 2 includes a rod body 20, the first end 2a of the rod body 20 passes through the end cover 3 and is located inside the valve cavity, and the second end of the rod body 20 is located outside the valve cavity, wherein the first end 2a and the second end are two ends arranged along the axial direction of the valve stem 2, respectively. The second end is usually provided with a handle 7 so that the operator can rotate the valve stem 2. Under the reciprocating rotation of the handle 7, the valve core assembly 4 can connect or close the channel between the first port 11 and the second port 12.

[0025] In the present invention, the first end 2a of the rod body 20 has a rotating foot 21, and the rotating foot 21 and the valve core assembly 4 are circumferentially limited so that the valve stem 2 drives the valve core assembly 4 to rotate; the rotating foot 21 has a first surface 211, and the end cover 3 has a second surface 31, wherein the first surface 211 and the second surface 31 are arranged opposite to each other along the axial direction. In the present invention, a friction reducing portion is arranged between the first surface 211 and the second surface 31, and the first surface 211 and the second surface 31 rotate by friction with the friction reducing portion, that is, the first surface 211 rotates relative to the second surface 31 by friction with the friction reducing portion.

[0026] The main function of the friction reducing part is to reduce the friction of the direct contact between the first surface 211 and the second surface 31. The friction reducing part can be installed on one of the first surface 211 and the second surface 31, and of course, the friction reducing part can also be installed on both the first surface 211 and the second surface 31.

[0027] Compared with the direct contact and frictional rotation of the first surface 211 and the second surface 31 in the background technology, a friction reducing portion is additionally provided between the first surface 211 and the second surface 31 in the utility model, and the first surface 211 and the second surface 31 rotate frictionally through the friction reducing portion, that is, the rotating foot 21 of the end cover 3 and the valve stem 2 is not in direct surface-to-surface frictional contact, which can reduce the machining accuracy of the end cover 3 and the valve stem 2 and reduce the machining cost. The friction reducing portion can be made of a material with relatively small friction resistance, which can reduce the friction force and thus reduce the rotational torque, reduce the sticking feeling of the valve stem 2 during rotation, and improve the smoothness of the rotation of the valve stem 2.

[0028] The anti-friction part can be arranged in various forms. Several arrangements of the anti-friction part are introduced below.

[0029] In a specific embodiment, the valve stem 2 is provided with a mounting groove 201, the friction reducing portion is positioned inside the mounting groove 201, and the friction reducing portion partially protrudes from the mounting groove 201 to be located between the first surface 211 and the second surface 31. The friction reducing portion can be fixed inside the mounting groove 201 by bonding or interference fit, and the fixation is simple and reliable. Of course, the friction reducing portion can also be fixed to the mounting groove 201 by a mechanical connector, and the fixation reliability is relatively high.

[0030] Of course, the mounting groove 201 can also be provided on the end cover 3 , for example, the mounting groove 201 is processed on the second surface 31 of the end cover 3 , and the friction reducing portion is installed on the end cover 3 .

[0031] In a specific embodiment, a mounting groove 201 is provided circumferentially of the rod body 20, and the mounting groove 201 is located at the root of the rod body 20 near the rotating foot 21. In this embodiment, the mounting groove 201 is provided on the rod body 20 instead of on the rotating foot 21, which is not only conducive to improving the use strength of the rotating foot 21, but also the mounting groove 201 is provided circumferentially of the rod body 20, and the mounting groove 201 has a relatively large space, which is conducive to improving the fixing reliability of the friction reduction part.

[0032] The friction reducing part includes a retaining ring 6 disposed inside the mounting groove 201, and the first surface 211 and the second surface 31 rotate by friction through the retaining ring 6. The retaining ring 6 has a simple structure and can be a circumferentially disconnected ring body. When installing, the retaining ring 6 is installed in the mounting groove 201 from the disconnected position, which is convenient to install.

[0033] Of course, the retaining ring 6 may also be a continuous ring structure.

[0034] The cross section of the retaining ring 6 can have various forms. For example, when the retaining ring 6 is installed on the rod body 20, the retaining ring 6 can be in point-to-surface contact with the second surface 31. For example, the contact area between the retaining ring 6 and the second surface 31 is very small, and the retaining ring 6 has a protrusion, which contacts the second surface 31. The retaining ring 6 can also be in point-to-line contact with the second surface 31. For example, the cross section of the retaining ring 6 is circular, and the contact position between the retaining ring 6 and the second surface 31 is the contact line. Of course, the retaining ring 6 can also be a circular retaining ring 6 with a rectangular or trapezoidal cross section, so that the retaining ring 6 and the second surface 31 can also be in surface-to-surface contact. .

[0035] Similarly, when the retaining ring 6 is installed on the end cover 3 , the retaining ring 6 and the first surface 211 may be in point-to-surface contact, line-to-surface contact, or surface-to-surface contact.

[0036] Please refer to Figures 8 to 10 , Figure 8 This is a schematic diagram of the structure of a plug valve in another embodiment of the utility model; Fig. 9 for Figure 8 A is a partial enlarged view of the structure shown; Fig.10 for Figure 8 Bottom view of the end cover 3 in the structure.

[0037] In another specific embodiment, at least one of the first surface 211 and the second surface 31 is provided with a wear-resistant coating 6', that is, the wear-resistant coating 6' can be provided only on the first surface 211 or the second surface 31, or can be provided on both the first surface 211 and the second surface 31. The friction reduction portion includes a wear-resistant coating, and the wear-resistant coating 6' can be a smooth wear-resistant material, and the wear-resistant material can be graphite or ceramic, etc. The thickness of the wear-resistant coating can be determined according to the specific situation, which will not be described in detail herein.

[0038] In this embodiment, the wear-resistant coating 6' is provided on the first surface 211 and / or the second surface 31, so that the space occupied by the valve cavity can be reduced as much as possible, and the plug valve has a compact structure and is relatively light.

[0039] The plug valve of the present invention further includes a spring 5, which is press-fitted between the valve core assembly 4 and the first end portion 2a, and is used to provide a force for the first surface 211 and the second surface 31 to abut against each other. The spring can be a cylindrical spring with a relatively simple structure, or a conical spring that occupies a relatively small space, or other forms of springs, as long as it can provide a force for the first surface 211 and the second surface 31 to abut against each other.

[0040] Specifically, the valve core assembly 4 includes a valve core sleeve 40, which has a recessed portion 4a opening toward the first end portion 2a, and a notch 41 is provided around the recessed portion 4a. The rotating foot 21 is at least partially located in the notch 41, so that the rotating foot 21 can drive the valve core sleeve 40 to rotate reciprocatingly.

[0041] Of course, the second surface 31 of the end cover 3 can also be processed by a lathe process to improve its processing accuracy, thereby reducing the friction between the first surface 211 and the second surface 31. Of course, the first surface 211 can also be processed by fine lathe process to reduce the friction between the first surface 211 and the second surface 31.

[0042] The above is a detailed introduction to a plug valve provided by the utility model. This article uses specific examples to illustrate the principle and implementation method of the utility model. The description of the above embodiment is only used to help understand the method and core idea of ​​the utility model. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the utility model, the utility model can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the utility model.

Claims

1. A plug valve, characterized in that: The invention comprises a valve body, a valve core assembly and a valve stem, wherein the valve body is further provided with an end cover, the plug valve is provided with a valve cavity, the valve core assembly is located inside the valve cavity, the first end portion of the valve stem passes through the end cover and is at least partially located inside the valve cavity, the valve stem has a rotating foot, and the rotating foot and the valve core assembly are circumferentially limited; the rotating foot and the end cover respectively have a first surface and a second surface arranged opposite to each other in the axial direction, a friction reducing portion is provided between the first surface and the second surface, and the first surface can rotate relative to the second surface through friction of the friction reducing portion.

2. The plug valve according to claim 1, characterized in that One of the valve stem or the end cover is provided with a mounting groove, the friction reducing portion is positioned in the mounting groove, and a portion of the friction reducing portion protrudes from the mounting groove to be located between the first surface and the second surface.

3. The plug valve according to claim 2, characterized in that The valve stem is provided with the mounting groove in its circumference, the friction reducing portion comprises a retaining ring provided inside the mounting groove, and the first surface and the second surface rotate by friction through the retaining ring.

4. The plug valve according to claim 2, characterized in that The second surface is provided with the mounting groove, and the friction reducing portion includes a retaining ring arranged inside the mounting groove.

5. The plug valve according to claim 3 or 4, characterized in that: The retaining ring rotates by line-surface contact friction or point-surface contact friction with the first surface or the second surface.

6. The plug valve according to claim 3 or 4, characterized in that: The retaining ring is in surface-to-surface contact with the first surface or the second surface.

7. The plug valve according to claim 1, characterized in that At least one of the first surface and the second surface is provided with a wear-resistant coating, and the friction-reducing portion includes the wear-resistant coating.

8. The plug valve according to claim 7, characterized in that The first surface and the second surface are both provided with the wear-resistant coating.

9. The plug valve according to any one of claims 1 to 4, 7 to 8, characterized in that: A spring is also included. The spring is pressed between the valve core assembly and the first end portion, and the spring is used to provide a force for the first surface and the second surface to abut against each other.

10. The plug valve according to claim 9, characterized in that The valve core assembly comprises a valve core sleeve, wherein the valve core sleeve has a recessed portion opening toward the first end portion, a periphery of the recessed portion has a notch, and the rotating foot is at least partially located in the notch.

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