Double-piston type stop check valve

Abstract

The utility model discloses a double-piston type stop check valve which comprises a valve body and a valve cover, a feeding flow channel and a discharging flow channel are arranged in the valve body, a valve seat is arranged between the feeding flow channel and the discharging flow channel, and a valve port communicated with the two flow channels is formed in the valve seat. A sealing mechanism is arranged above the valve port; the sealing mechanism comprises a valve clack and a valve rod, the valve rod can reciprocate between an initial position and a lifting position, when the valve rod is located at the initial position, the valve clack is pressed above the valve seat, the valve clack seals the valve port, when the valve rod is located at the lifting position, limitation on the valve clack is relieved, and the valve clack can move up and down under the action of fluid pressure; a first guide sleeve for guiding the valve rod is arranged above the valve clack, the valve clack and the first guide sleeve move synchronously, a second guide sleeve for guiding the valve clack is assembled on the periphery of the first guide sleeve, and the first guide sleeve and the second guide sleeve are coaxially arranged. By arranging the two guide sleeves, the valve rod and the valve clack can be limited and guided at the same time, and the sealing effect is guaranteed.

Description

Technical Field

[0001] The utility model belongs to the technical field of stop check valves, and in particular relates to a double-piston stop check valve. Background Art

[0002] A stop-check valve is a multi-purpose valve that combines the functions of a stop valve and a check valve. Its stem and disc are separate components. When the stem descends, pressing the disc against the valve seat, it functions as a stop valve. When the stem ascends, it functions as a check valve. Therefore, it is widely used in pipelines requiring both stop and check valves, effectively saving installation costs and space. To improve the fit between the stem and disc and enhance the disc's sealing effectiveness, a stem guide sleeve is typically installed within the valve body. This sleeve, in conjunction with the stem, forms a piston structure to guide the stem throughout its opening and closing strokes. However, the stem and disc of a stop-check valve are separate components. Existing stop-check valves only provide positional guidance for the stem, not the disc. When the valve body is installed in challenging installation conditions, where it cannot be installed at a conventional angle, the disc's center of gravity shifts, compromising the seal between the disc and the seat. Summary of the Invention

[0003] The utility model addresses the problem that the sealing effect of existing stop check valves is affected by the installation angle limitation, and provides a double-piston stop check valve. The purpose of the utility model is achieved through the following technical solutions:

[0004] When the closure is closed, the closure is closed and the closure is closed, so that the closure is closed and the closure is closed, and the closure is closed after the closure is closed. When the closure is closed, the closure is closed and the closure is closed, so that the closure is closed and the closure is closed. When the closure is closed, the closure is closed and the closure is closed, the closure is closed and the closure is closed. When the closure is closed, the closure is closed and the closure is closed, the closure is closed and the closure is closed. When the closure is closed, the closure is closed and the closure is closed, the closure is closed and the closure is closed.

[0005] Preferably, the valve flap includes an assembly column and a sealing flap arranged below the assembly portion, the top of the assembly column is provided with an assembly groove with an upward opening, and the lower end of the first guide sleeve is screwed into the assembly groove.

[0006] Preferably, the second guide sleeve is fixed in the valve body, the assembly column is slidably arranged in the second guide sleeve, the inner diameter of the second guide sleeve matches the outer diameter of the assembly column; the axial height of the second guide sleeve is greater than the axial height of the first guide sleeve.

[0007] Preferably, a limiting ring is protruding from the outer wall of the first guide sleeve, the limiting ring abuts against the upper end surface of the assembly column, and the two are spot-welded and fixed.

[0008] Preferably, the outer diameter of the limiting ring matches the inner diameter of the first guide sleeve, and the second guide sleeve guides the valve disc and the first guide sleeve synchronously.

[0009] Preferably, the upper end of the second guide sleeve is provided with an outward-turned edge that turns outward horizontally; the upper end surface of the valve body is provided with an upper sealing groove, and the lower end surface of the valve cover is provided with a lower sealing groove that is aligned with the upper sealing groove. When the valve cover and the valve body are fixedly assembled, the upper sealing groove and the lower sealing groove jointly define an annular cavity, the outward-turned edge is extended and limited to the annular cavity, and sealing gaskets are provided above and below the outward-turned edge.

[0010] Preferably, the valve stem is arranged in sections, which include an operating section and a guide section from top to bottom. The guide section is inserted into the first guide sleeve, and the outer diameter of the guide section matches the inner diameter of the first guide sleeve.

[0011] Preferably, the operating section passes through the top of the valve cover, a hand wheel is installed on the top of the operating section, an adjusting nut is installed above the valve cover, and an adjusting thread cooperating with the adjusting nut is provided on the operating section.

[0012] Preferably, a conical sealing head is provided at the bottom of the sealing flap, and a conical outward expansion opening having the same taper as that of the conical sealing head is provided at the upper edge of the valve opening.

[0013] Preferably, a jacket is provided around the outside of the valve body, and a heat preservation cavity for filling with a heat preservation medium is formed between the jacket and the valve body.

[0014] Compared with the prior art, the utility model discloses a double-piston stop check valve, which forms two sets of piston structures by arranging a coaxial first guide sleeve and a second guide sleeve in the valve body, which cooperate with the valve stem and the valve disc respectively, and can simultaneously limit and guide the valve stem and the valve disc, so that when the valve is installed at an unconventional angle, the fit between the valve disc and the valve seat sealing surface is not reduced, thereby ensuring the sealing effect; the first guide sleeve structure is reasonably arranged, and the setting of its limit ring can ensure that the first guide sleeve and the valve disc are firmly connected so that the two move synchronously, and can also realize the guidance of the first guide sleeve by the second guide sleeve, thereby further improving the coaxiality of the operation of the valve stem and the valve disc, and ensuring the sealing effect of the valve body; the valve disc and the valve seat adopt conical sealing, which has a better sealing effect, and the conical sealing surfaces that cooperate with each other can be automatically aligned, thereby improving the fit between the two, and are wear-resistant and have a long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the structure of the utility model;

[0016] Figure 2 This is a schematic diagram of the sealing mechanism structure in the utility model;

[0017] Markings in the figure: valve body 10; feed flow channel 11; discharge flow channel 12; valve seat 13; valve port 131; tapered outward expansion port 132; valve cover 20; valve disc 31; assembly column 311; sealing bend; tapered sealing head 3121; valve stem 32; operating section 321; guide section 322; first guide sleeve; limiting ring; second guide sleeve 34; outward edge 341; adjusting nut 35; handwheel 36; jacket 40; insulation chamber 41. DETAILED DESCRIPTION

[0018] The present invention will be further described below with reference to the embodiments shown in the accompanying drawings:

[0019] See also Figure 1 、 Figure 2 The present embodiment discloses a double-piston stop check valve, comprising a valve body 10 and a valve cover 20. A feed channel 11 and a discharge channel 12 are provided in the valve body 10, a valve seat 13 is provided between the feed channel 11 and the discharge channel 12, and a valve port 131 is provided on the valve seat 13 for connecting the two channels; a jacket 40 is provided around the outside of the valve body 10, and an insulation chamber 41 for filling with an insulation medium is formed between the jacket 40 and the valve body 10.

[0020] A sealing mechanism for sealing and opening the valve port 131 is provided above the valve port 131; the sealing mechanism includes a valve disc 31 and a valve stem 32 which are separately provided, and the valve stem 32 can move back and forth between an initial position and an upper lifting position under the action of an external force. When the valve stem 32 is in the initial position, the valve disc 31 is pressed against the valve seat 13, and the valve disc 31 seals the valve port 131, and at this time the valve realizes a shut-off function; when the valve stem 32 is in the upper lifting position, the restriction on the valve disc 31 is released, and the valve disc 31 can move up and down under the action of fluid pressure, and at this time the valve realizes a check function; a first guide sleeve for guiding the valve stem 32 is provided above the valve disc 31, and the valve disc 31 moves synchronously with the first guide sleeve, and the periphery of the first guide sleeve is equipped with a second guide sleeve 34 for guiding the valve disc 31, and the first guide sleeve and the second guide sleeve 34 are coaxially arranged. By arranging a coaxial first guide sleeve and a second guide sleeve 34 in the valve body 10, which cooperate with the valve stem 32 and the valve disc 31 respectively, two sets of piston structures are formed. At the same time, the valve stem 32 and the valve disc 31 are limited and guided. When the valve is installed at an unconventional angle, the fit between the valve disc 31 and the sealing surface of the valve seat 13 is not reduced, thereby ensuring the sealing effect.

[0021] The valve flap 31 includes an assembly post 311 and a sealing flap 312 arranged below the assembly part. The top of the assembly post 311 is provided with an assembly groove opening upward, and the lower end of the first guide sleeve is screwed into the assembly groove to achieve a fixed connection between the two; the second guide sleeve 34 is fixed in the valve body 10, and the assembly post 311 is slidably set in the second guide sleeve 34, and the inner diameter of the second guide sleeve 34 matches the outer diameter of the assembly post 311; a limiting ring is protruding from the outer wall of the first guide sleeve, and the limiting ring abuts against the upper end face of the assembly post 311, and the two are spot welded and fixed to improve the connection stability between the two; the outer diameter of the limiting ring matches the inner diameter of the first guide sleeve, and the axial height of the second guide sleeve 34 is greater than the axial height of the first guide sleeve, and the second guide sleeve 34 synchronously guides the valve flap 31 and the first guide sleeve. The setting of the limit ring can ensure that the first guide sleeve and the valve disc 31 are firmly connected so that the two move synchronously, and can also realize the guidance of the first guide sleeve by the second guide sleeve 34, thereby further improving the coaxiality of the operation of the valve stem 32 and the valve disc 31, and improving the fit between the valve disc 31 and the valve seat 13, thereby ensuring the sealing effect of the valve body 10.

[0022] The upper end of the second guide sleeve 34 is provided with a horizontally outward-turned lip 341. The upper end surface of the valve body 10 is provided with an upper sealing groove, and the lower end surface of the valve cover 20 is provided with a lower sealing groove aligned with the upper sealing groove. When the valve cover 20 and the valve body 10 are fixedly assembled, the upper and lower sealing grooves together define an annular cavity. The lip 341 extends and limits within the annular cavity, and sealing gaskets are provided above and below the lip 341. The provision of the lip 341 facilitates the assembly of the second guide sleeve 34 and ensures the sealing of the valve. When the valve cover 20 and the valve body 10 are fastened together, the second guide sleeve 34 is quickly and conveniently fixed.

[0023] The valve stem 32 is arranged in sections, which include an operating section 321 and a guide section 322 from top to bottom. The guide section 322 is inserted into the first guide sleeve, and the outer diameter of the guide section 322 matches the inner diameter of the first guide sleeve; the operating section 321 passes through the top of the valve cover 20, and the top of the operating section 321 is equipped with a handwheel 36. The top of the valve cover 20 is equipped with an adjusting nut 35. The operating section 321 is provided with an adjusting thread that cooperates with the adjusting nut 35. By rotating the handwheel 36, the position of the valve stem 32 can be adjusted.

[0024] A conical sealing head 3121 is provided at the bottom of the sealing flap 312, and a conical outward expansion opening 132 having the same taper as the conical sealing head 3121 is provided at the upper edge of the valve port 131. The valve flap 31 and the valve seat 13 adopt conical sealing, which has a better sealing effect. The conical sealing surfaces that cooperate with each other can achieve automatic alignment, thereby improving the cooperation between the two, and are wear-resistant and have a long service life.

[0025] It should be understood that in the claims and description of this utility model, all phrases "including..." should be understood as open-ended, meaning equivalent to "at least including...", and should not be understood as closed-ended, meaning "only including...". The terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the quantity of the technical features indicated.

[0026] The above is only a specific implementation method of the present invention, but the scope of protection of the present invention is not limited to this. Any changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should be covered by the scope of protection of the utility model.

Claims

1. A double-piston stop check valve, comprising a valve body and a valve cover, wherein the valve body is provided with a feed flow channel and a discharge flow channel, a valve seat is provided between the feed flow channel and the discharge flow channel, and a valve port is provided on the valve seat to connect the two flow channels; characterized in that: A sealing mechanism for sealing and opening the valve port is provided above the valve port, and the sealing mechanism includes a valve disc and a valve stem which are separately provided; the valve stem can move back and forth between an initial position and an upper lifting position under the action of an external force, and the valve disc can move back and forth up and down, and when the valve stem is in the initial position, the valve disc is pressed against the valve seat so that the valve disc seals the valve port, and when the valve stem is in the upper lifting position, the restriction on the valve disc is released, and the valve disc can move up and down under the action of fluid pressure; a first guide sleeve for guiding the valve stem is provided above the valve disc, and the valve disc moves synchronously with the first guide sleeve, and a second guide sleeve for guiding the valve disc is assembled on the periphery of the first guide sleeve, and the first guide sleeve and the second guide sleeve are coaxially arranged.

2. A double-piston stop check valve according to claim 1, characterized in that: The valve flap includes an assembly column and a sealing flap arranged below the assembly column. The top of the assembly column is provided with an assembly groove with an opening facing upwards. The lower end of the first guide sleeve is screwed into the assembly groove.

3. A double-piston stop check valve according to claim 2, characterized in that: The second guide sleeve is fixed in the valve body, the assembly column is slidably arranged in the second guide sleeve, the inner diameter of the second guide sleeve matches the outer diameter of the assembly column; the axial height of the second guide sleeve is greater than the axial height of the first guide sleeve.

4. A double-piston stop check valve according to claim 3, characterized in that: A limiting ring is protruding from the outer wall of the first guide sleeve. The limiting ring abuts against the upper end surface of the assembly column, and the two are fixedly connected by spot welding.

5. A double-piston stop check valve according to claim 4, characterized in that: The outer diameter of the limiting ring matches the inner diameter of the first guide sleeve, and the second guide sleeve guides the valve disc and the first guide sleeve synchronously.

6. A double-piston stop check valve according to any one of claims 1 to 5, characterized in that: The upper end of the second guide sleeve is provided with an outward-turned edge that turns outward horizontally; the upper end surface of the valve body is provided with an upper sealing groove, and the lower end surface of the valve cover is provided with a lower sealing groove that is aligned with the upper sealing groove. When the valve cover and the valve body are fixedly assembled, the upper sealing groove and the lower sealing groove jointly define an annular cavity, the outward-turned edge is extended and limited to the annular cavity, and sealing gaskets are provided above and below the outward-turned edge.

7. The double-piston stop check valve according to claim 1, characterized in that: The valve stem is arranged in sections, which include an operating section and a guide section from top to bottom. The guide section is inserted into the first guide sleeve, and the outer diameter of the guide section matches the inner diameter of the first guide sleeve.

8. The double-piston stop check valve according to claim 7, characterized in that: The operating section passes through the top of the valve cover, the top of the operating section is equipped with a hand wheel, the upper part of the valve cover is equipped with an adjusting nut, and the operating section is provided with an adjusting thread that matches the adjusting nut.

9. A double-piston stop check valve according to any one of claims 2 to 5, characterized in that: A conical sealing head is provided at the bottom of the sealing flap, and a conical outward expansion opening with the same taper as the conical sealing head is provided at the upper edge of the valve port.

10. The double-piston stop check valve according to claim 1, characterized in that: A jacket is provided around the outside of the valve body, and a heat preservation cavity for filling with heat preservation medium is formed between the jacket and the valve body.

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