CN220668427U - Gate valve with pressure protection valve - Google Patents
Gate valve with pressure protection valve Download PDFInfo
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- CN220668427U CN220668427U CN202322359375.4U CN202322359375U CN220668427U CN 220668427 U CN220668427 U CN 220668427U CN 202322359375 U CN202322359375 U CN 202322359375U CN 220668427 U CN220668427 U CN 220668427U
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 153
- 238000006073 displacement reaction Methods 0.000 claims abstract description 8
- 238000000034 method Methods 0.000 claims abstract description 4
- 238000007789 sealing Methods 0.000 claims description 7
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000008400 supply water Substances 0.000 description 1
Abstract
The utility model discloses a gate valve with a pressure protection valve, which comprises a valve body, a valve plate and a valve rod, wherein a water inlet channel, a valve cavity and a water outlet channel are arranged in the valve body; the method is characterized in that: a pressure protection valve is arranged at the water inlet end of the water outlet channel; the pressure protection valve is provided with a positive valve core and a negative valve core; when the water pressure in the water inlet channel is larger than the water pressure in the water outlet channel and the first pressure difference generated on the positive valve core is larger than the positive threshold value of the pressure protection valve, the positive valve core is opened in a displacement way and can flow positively; when the water pressure in the water outlet channel is larger than the water pressure in the water inlet channel and the second pressure difference generated for the negative valve core is larger than the negative threshold value of the pressure protection valve, the negative valve core is opened in a displacement mode and can flow reversely. The utility model can prevent water from flowing backwards by opening the positive valve core in one direction to protect the normal movement of the system, and simultaneously, the negative valve core is automatically opened to release pressure by flowing in the negative direction when the user side is in serious overpressure, so that the overpressure automatic protection is realized.
Description
Technical Field
The utility model belongs to the technical field of valves, and particularly relates to a gate valve with a pressure protection valve.
Background
The water meter gate valve is a functional valve which is arranged in a water supply pipeline system and connected with a water meter, can be used for controlling the opening or closing of a water supply pipeline of a user, and is convenient for the user to install or maintain a room.
Referring to fig. 1, the existing gate valve 1 comprises a valve body 1-1 and a valve plate 1-2, wherein a water inlet channel 1-11, a valve cavity 1-12 and a water outlet channel 1-13 are arranged in the valve body 1-1, the valve plate 1-2 is arranged in the valve cavity 1-12, and the opening or closing between the water inlet channel 1-11 and the water outlet channel 1-13 of the gate valve 1 is controlled by the up-and-down displacement of the valve plate 1-2 in use; the valve plate 1-2 is normally positioned in the upper position and kept in an open state. However, during use, the following deficiencies were found to exist and were analyzed as follows:
firstly, because the existing gate valve is a shutter plate of an opening and closing piece, the moving direction of the shutter plate is vertical to the fluid direction, and the gate valve can only be fully opened and fully closed; the normal water supply pressure is 0.8MPa, and the gate valve outlet is connected with a user pipeline, and the gate valve inlet is connected with a water meter pipeline; therefore, the water flow backflow and the water hammer phenomenon exist at the moment of water closing, and the stable and normal operation of the system is affected;
secondly, in order to solve the first problem, a check valve is usually disposed between the gate valve outlet and the user pipeline, and when a serious overpressure (e.g. greater than 2 MPa) occurs between the gate valve outlet and the user pipeline (i.e. at the user end), the check valve cannot flow back, so that pressure cannot be effectively relieved, and at this time, potential safety hazards, such as a pipe explosion, exist.
Disclosure of Invention
The utility model provides a gate valve with a pressure protection valve, which solves the problem that the existing valve plate has water-closing backflow and can solve the problem that the existing one-way valve cannot effectively release pressure when the user side is severely overpressured, so that potential safety hazards exist.
In order to achieve the above purpose, the scheme of the utility model is as follows: the gate valve with the pressure protection valve comprises a gate valve body, wherein the gate valve body comprises a valve body, a valve plate and a valve rod, a water inlet channel, a valve cavity and a water outlet channel are arranged in the valve body, and the valve plate can move up and down in the valve cavity to open or close the gate valve; the method is characterized in that: a pressure protection valve is arranged at the water inlet end of the water outlet channel; the pressure protection valve is provided with a positive valve core and a negative valve core; when the water pressure in the water inlet channel is larger than the water pressure in the water outlet channel and the first pressure difference generated on the positive valve core is larger than the positive threshold value of the pressure protection valve, the positive valve core is opened in a displacement way and can flow positively; when the water pressure in the water outlet channel is larger than the water pressure in the water inlet channel and the second pressure difference generated for the negative valve core is larger than the negative threshold value of the pressure protection valve, the negative valve core is opened in a displacement mode and can flow reversely.
Preferably, the pressure protection valve comprises a valve seat, a positive valve core, a negative valve core, a first spring and a second spring; the valve seat is fixed in the water outlet channel, and a side channel is arranged on the valve seat; the water inlet end of the water outlet channel is provided with a first valve hole; the first spring is arranged between the positive valve core and the valve seat; the center of the valve seat is provided with a first sliding hole, and the center of the positive valve core is provided with a second sliding hole; the negative valve core is in sliding fit with the first sliding hole; the negative valve core is in clearance fit with the second sliding hole; the second sliding hole is provided with a second valve hole with a larger aperture at one end facing the water inlet channel; one end of the negative valve core is provided with a core disc and is used for opening or closing the second valve hole; the second spring is arranged between the positive valve core and the negative valve core.
Preferably, the valve seat is provided with a concave cavity in one end facing the valve cavity; the first spring and the second spring are both positioned in the concave cavity; two ends of the first spring are respectively propped against the valve seat and the positive valve core; a shoulder is arranged in the middle of the negative valve core; and two ends of the second spring are respectively propped against the stop shoulder and the positive valve core.
Preferably, the first spring and the second spring are conical coil springs.
Further, a third sealing ring is sleeved on the positive valve core; and the negative valve core is sleeved with a fourth sealing ring.
Preferably, the ratio of the first cross-sectional area (S1) of the other end of the negative spool to the second cross-sectional area (S2) of the spool is less than 0.5.
The utility model has the beneficial effects that:
firstly, the pressure protection valve is automatically closed in a one-way mode after the user side closes the water state, so that the water outlet end of the gate valve is prevented from flowing back into the water inlet end, the water flow is prevented from flowing back and the water hammer phenomenon is prevented, and the stable and normal operation of a system (such as a water meter) is ensured to be influenced;
secondly, the pressure protection valve can be automatically opened when the user side opens water, so that normal running water movement can be realized;
thirdly, the negative valve core of the pressure protection valve in the gate valve automatically opens and releases pressure when water in the user terminal is over-pressurized, so that the water pressure between the gate valve outlet channel and the water inlet channel is always kept in self-adaptive balance, potential safety hazards are prevented, and automatic protection is achieved;
fourth, the utility model can solve the problem that the existing valve plate has water-closing backflow and can overcome the problem that the existing one-way valve cannot effectively release pressure when the user side is severely overpressured, so that potential safety hazard exists; the positive valve core is opened in one direction to flow positively, so that the water can be prevented from flowing backwards to protect the normal motion of the system, and the negative valve core is opened automatically to flow negatively to release pressure when the user side is in serious overpressure, so that the overpressure automatic protection is realized.
Drawings
Fig. 1 is a view showing an operation state of a gate valve according to the prior art when a user opens water.
Fig. 2 is a view showing an operation state of a gate valve with a pressure protection valve according to the present utility model when the gate valve is opened and a user side is opened with water.
Fig. 3 is an enlarged view at a in fig. 2.
Fig. 4 is a view showing an operation state of a gate valve with a pressure protection valve according to the present utility model when the gate valve is opened and a user side is closed.
FIG. 5 is an enlarged view at B in FIG. 4
Fig. 6 is a view showing an operation state of a gate valve with a pressure protection valve according to the present utility model when the gate valve is opened and the user terminal is over-pressurized in a water-shut state.
Fig. 7 is an enlarged view at C in fig. 6.
Fig. 8 is a schematic structural view of the pressure protection valve.
Fig. 9 is an exploded view of the pressure protection valve.
Fig. 10 is a schematic structural view of a valve seat of the pressure protection valve.
Detailed Description
The utility model is further illustrated by the following examples in conjunction with the accompanying drawings:
examples: referring to fig. 2-3, a gate valve with a pressure protection valve comprises a valve body N-1, a valve plate N-2, a valve rod N-3 and the pressure protection valve 2, wherein a water inlet channel N-11, a valve cavity N-12 and a water outlet channel N-13 are arranged in the valve body N-1, the lower end of the valve rod N-3 is connected with the valve plate N-2, and the valve rod N-3 is used for controlling the valve plate N-2 to move up and down in the valve cavity N-12 so as to open or close the gate valve; when in use, the valve plate N-2 is vertically displaced to realize the opening or closing of the water inlet channel N-11 and the water outlet channel N-13 of the control gate valve; the valve plate N-2 is positioned at the upper position in a normal state to keep the gate valve in an open state.
The key point of the utility model is that: referring to fig. 2-3, a pressure protection valve 2 is provided at the water inlet end of the water outlet passage N-11.
In the present embodiment, referring to fig. 8-10, the pressure protection valve 2 includes a valve seat 2-3, a positive spool 2-1 and a negative spool 2-2, a first spring 2-4 and a second spring 2-5; the valve seat 2-3 is fixed in the water outlet channel N-13 (see fig. 2), and a side channel 2-31 is arranged on the valve seat 2-3; the water inlet end of the water outlet channel N-13 is provided with a first valve hole 2-6 (see figure 2); the first spring 2-4 is arranged between the positive valve core 2-1 and the valve seat 2-3; the center of the valve seat 2-3 is provided with a first sliding hole 2-32, and the center of the positive valve core 2-1 is provided with a second sliding hole 2-11; the negative valve core 2-2 is in sliding fit with the first sliding hole 2-32; the negative valve core 2-2 is in clearance fit with the second sliding hole 2-11; the right end of the second sliding hole 2-11 (i.e. the end facing the water inlet channel N-11) is provided with a second valve hole 2-12 with a larger aperture; the right end of the negative valve core 2-2 is provided with a core disc 2-21 and is used for opening or closing the second valve hole 2-12; the second spring 2-5 is arranged between the positive valve core 2-1 and the negative valve core 2-2. Specifically, the positive valve core 2-1 is disc-shaped, and a conical surface 2-13 is sealed between the positive valve core 2-1 and the first valve hole 2-6. When in operation, the pressure protection valve 2 is arranged at the water inlet end of the water outlet channel N-13 and is provided with a positive valve core 2-1 and a negative valve core 2-2; when the water pressure in the water inlet channel N-11 is larger than the water pressure in the water outlet channel N-13 and the pressure difference generated on the positive valve core 2-1 is larger than the positive threshold value of the pressure protection valve 2, the positive valve core 2-1 is opened in a displacement way and flows positively (see fig. 2-3); the negative spool 2-2 is displaced open and flows in reverse when the water pressure in the water outlet passage N-13 is greater than the water pressure in the water inlet passage N-11 and the pressure difference generated to the negative spool 2-2 is greater than the negative threshold of the pressure protection valve 2 (see fig. 6-7).
Referring to fig. 8-10, the valve seat 2-3 is provided with a concave cavity 2-33 in one end facing the valve cavity N-12; the first springs 2-4 and the second springs 2-5 are positioned in the concave cavities 2-33; two ends of the first spring 2-4 are respectively propped against the valve seat 2-3 and the positive valve core 2-1; the middle part of the negative valve core 2-2 is provided with a stop shoulder 2-22; two ends of the second spring 2-5 are respectively abutted against the stop shoulder 2-22 and the positive valve core 2-1.
Referring to fig. 8 to 10, the first springs 2 to 4 and the second springs 2 to 5 employ conical coil springs.
Referring to fig. 8-10, in addition, a third sealing ring 2-7 is sleeved on the positive valve core 2-1; and a fourth sealing ring 2-8 is sleeved on the negative valve core 2-2.
Referring to fig. 8-10, in addition, the ratio of the first cross-sectional area S1 of the other end of the negative spool 2-2 to the second cross-sectional area S2 of the spool 2-21 is less than 0.5.
The working principle of the utility model under different working states is as follows:
referring to fig. 3-4, when the user opens water (the gate valve is in a normal open state), the water supply end enters the valve cavity N-12 through the water inlet channel N-11 of the valve body N-1 (when the valve plate 1-2 is kept in an open state), the water pressure P1 (completely depressurized and 0 Mpa) in the water outlet channel N-13 of the valve body N-1 is lower than the water pressure P2 (i.e. the water supply pressure is 0.8 Mpa) in the water inlet channel N-11 due to the water pressure P1 (completely depressurized and 0 Mpa) of the user end when water (such as water for opening a faucet) is used, and the first pressure difference (P2 x S3-P1 x S3) of the positive valve core 2-1 is greater than the positive threshold F1 of the pressure protection valve 2, wherein S3 is the cross-sectional area of the positive valve core 2-1. Wherein the forward threshold (F1) of the pressure protection valve 2 is defined as: the positive spool 2-1 overcomes the force of the first spring 2-4 and creates the minimum force required to disengage the seal with the first valve bore 2-6 (i.e., the minimum force required to allow the positive spool 2-1 to displace open to the left against the force of the first spring 2-4). When water is normally supplied and opened, the first pressure difference (P2 x S3-P1 x S3) received by the positive valve core 2-1 is greater than the positive threshold F1 of the pressure protection valve 2, the positive valve core 2-1 is displaced to the left and opened, the positive valve core 2-1 and the first valve hole 2-6 are separated from sealing to form a gap channel, and at this time, water in the water inlet channel N-11 sequentially enters the water outlet channel N-13 through the first valve hole 2-6 and the side channel 2-31 to realize normal water use of a user. At this time, the water flow normally passes through the water inlet channel N-11, the valve cavity N-12, the first valve hole 2-6, the side channel 2-31 and the water outlet channel N-13 in the gate valve in sequence to keep the forward flow when in use under normal water pressure (see fig. 2-3).
When the user (the gate valve is normally opened) just closes the water, the water inlet channel N-1 of the valve body N-1 continues to supply water and enters the water outlet channel N-13, the water pressure P1 in the water outlet channel N-13 is continuously increased until the water pressure P1 at the water outlet end of the water outlet channel N-13 is smaller than the forward threshold F1 of the pressure protection valve 2 and the water pressure P2 in the water inlet channel N-11 is still 0.8Mpa after the first pressure difference (P2S 3-P1S 3) is smaller than the forward threshold F1 of the pressure protection valve 2, and the water pressure P1 at the water outlet end of the water outlet channel N-13 is smaller than 0.8Mpa after the first pressure difference (P2S 3-S3) is smaller than the forward threshold F1 of the pressure protection valve 2. And because the water pressure P1 in the water outlet channel N-13 is always smaller than the water pressure P2 in the water inlet channel N-11 in the resetting and closing process of the positive valve core 2-1, the water in the water outlet channel N-13 cannot flow back into the water inlet channel N-11, and the water flow movement is directly blocked after the positive valve core 2-1 of the pressure protection valve 2 is reset and closed (see fig. 3-4), the valve is equivalent to the function of a one-way valve, the water pressure stability can be ensured, and meanwhile, the water always flows forward before the positive valve core 2-1 is closed, so that the reverse backflow and water hammer phenomenon of the water can be avoided at the moment of water closing, and the stable and normal operation of a system (such as a water meter) is ensured.
Referring to fig. 6-7, when the user is in the water-off state, if an overpressure occurs in the water pressure between the user side and the water outlet channel N-13 of the valve body N-1 (i.e. the water pressure P1 in the water outlet channel N-13 is greater than 2 Mpa) and is far greater than the water pressure in the water supply side (i.e. the water pressure P2 in the water inlet channel N-11 of the valve body N-1 is 0.8 Mpa). At this time, the positive spool 2-1 receives the first pressure difference in the rightward direction, and thus the positive spool 2-1 remains sealed with the first valve hole 2-6 while remaining closed. But when P1 is greater than 2Mpa, the P1S 1 is greater than P2S 2 and the negative spool 2-2 is subjected to a second pressure difference and directed to the right, where (P1S 1-P2S 2) is greater than the negative threshold F2 of the pressure protection valve 2. Wherein the negative threshold (F2) of the pressure protection valve 2 is defined as: the pressure protection valve 2 overcomes the acting force of the second spring 2-5 to generate the minimum force required for separating the core disc 2-21 at the right end of the negative valve core 2-2 from the second valve hole 2-12 (i.e., the minimum force required for the negative valve core 2-2 to be able to displace rightward against the acting force of the second spring 2-5). Wherein, the first cross-sectional area of the other end (left end) of the negative valve core 2-2 is S1, and the second cross-sectional area S2 of the core disc 2-21. When (P1 x S1-P2 x S2) is greater than F2, the negative valve core 2-2 overcomes the pressure of the second spring 2-5 and compresses the second spring 2-5, the negative valve core 2-2 slides rightwards relative to the positive valve core 2-1 and separates the valve core 2-21 from the second valve hole 2-12 to open, at this time, high-pressure water (2 Mpa) between the user end and the water outlet channel N-13 of the valve body N-1 sequentially passes through the side channel 2-31, the fit gap between the negative valve core 2-2 and the second sliding hole 2-12, the second valve hole 2-12 and then enters the valve cavity N-12 and the water inlet channel N-11 to complete negative flow pressure relief until the water pressure P1 between the user end and the water outlet channel N-13 of the valve body N-1 drops to the safety pressure P3, at this time, the second pressure difference (P3 x S1-P2) received by the negative valve core 2-2 is smaller than the threshold value F2 of the pressure protection valve core 2, and the negative valve core 2-2 is automatically reset after the second valve hole 2-12 and the second valve hole 2-12 is closed, thereby the valve core 2-2 is automatically reset, and the negative pressure relief function is prevented from being closed for a long time.
Therefore, the utility model can solve the problem that the existing valve plate has water-closing backflow and can solve the problem that the existing one-way valve cannot effectively release pressure when the user side is severely overpressured, so that potential safety hazard exists. The positive valve core is opened in one direction to flow positively, so that the water can be prevented from flowing backwards to protect the normal motion of the system, and the negative valve core is opened automatically to flow negatively to release pressure when the user side is in serious overpressure, so that the overpressure automatic protection is realized.
The foregoing describes in detail preferred embodiments of the present utility model. It should be understood that numerous modifications and variations can be made in accordance with the concepts of the utility model by one of ordinary skill in the art without undue burden. Therefore, all technical solutions which can be obtained by logic analysis, reasoning or limited experiments based on the prior art by the person skilled in the art according to the inventive concept shall be within the scope of protection defined by the claims.
Claims (6)
1. The gate valve with the pressure protection valve comprises a gate valve body, wherein the gate valve body comprises a valve body (N-1), a valve plate (N-2) and a valve rod (N-3), a water inlet channel (N-11), a valve cavity (N-12) and a water outlet channel (N-13) are arranged in the valve body (N-1), and the valve plate (N-2) can move up and down in the valve cavity (N-12) to open or close the gate valve; the method is characterized in that: a pressure protection valve (2) is arranged at the water inlet end of the water outlet channel (N-13);
the pressure protection valve (2) is provided with a positive valve core (2-1) and a negative valve core (2-2); when the water pressure in the water inlet channel (N-11) is larger than the water pressure in the water outlet channel (N-13) and the first pressure difference generated on the positive valve core (2-1) is larger than the positive threshold value of the pressure protection valve (2), the positive valve core (2-1) is opened in a displacement mode and can flow positively; when the water pressure in the water outlet channel (N-13) is larger than the water pressure in the water inlet channel (N-11) and the second pressure difference generated on the negative valve core (2-2) is larger than the negative threshold value of the pressure protection valve (2), the negative valve core (2-2) is opened in a displacement mode and can flow reversely.
2. A gate valve with pressure protection valve as defined in claim 1, wherein: the pressure protection valve (2) comprises a valve seat (2-3), a positive valve core (2-1) and a negative valve core (2-2), a first spring (2-4) and a second spring (2-5); the valve seat (2-3) is fixed in the water outlet channel (N-13), and a side channel (2-31) is arranged on the valve seat (2-3); the water inlet end of the water outlet channel (N-13) is provided with a first valve hole (2-6); the first spring (2-4) is arranged between the positive valve core (2-1) and the valve seat (2-3); the center of the valve seat (2-3) is provided with a first sliding hole (2-32), and the center of the positive valve core (2-1) is provided with a second sliding hole (2-11); the negative valve core (2-2) is in sliding fit with the first sliding hole (2-32); the negative valve core (2-2) is in clearance fit with the second sliding hole (2-11); the second sliding hole (2-11) is provided with a second valve hole (2-12) with a larger aperture at one end facing the water inlet channel (N-11); one end of the negative valve core (2-2) is provided with a core disc (2-21) and is used for opening or closing the second valve hole (2-12); the second spring (2-5) is arranged between the positive valve core (2-1) and the negative valve core (2-2).
3. A gate valve with pressure protection valve as claimed in claim 2, wherein: the valve seat (2-3) is provided with a concave cavity (2-33) in one end facing the valve cavity (N-12); the first spring (2-4) and the second spring (2-5) are both positioned in the concave cavity (2-33); two ends of the first spring (2-4) are respectively propped against the valve seat (2-3) and the positive valve core (2-1); a shoulder (2-22) is arranged in the middle of the negative valve core (2-2); two ends of the second spring (2-5) are respectively abutted against the stop shoulder (2-22) and the positive valve core (2-1).
4. A gate valve with pressure protection valve as claimed in claim 2, wherein: the first springs (2-4) and the second springs (2-5) adopt conical spiral springs.
5. A gate valve with pressure protection valve as defined in claim 2, wherein: a third sealing ring (2-7) is sleeved on the positive valve core (2-1); a fourth sealing ring (2-8) is sleeved on the negative valve core (2-2).
6. A gate valve with pressure protection valve as defined in claim 2, wherein: the ratio of the first cross-sectional area (S1) of the other end of the negative valve core (2-2) to the second cross-sectional area (S2) of the valve core disc (2-21) is less than 0.5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322359375.4U CN220668427U (en) | 2023-08-31 | 2023-08-31 | Gate valve with pressure protection valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322359375.4U CN220668427U (en) | 2023-08-31 | 2023-08-31 | Gate valve with pressure protection valve |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220668427U true CN220668427U (en) | 2024-03-26 |
Family
ID=90337387
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202322359375.4U Active CN220668427U (en) | 2023-08-31 | 2023-08-31 | Gate valve with pressure protection valve |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN220668427U (en) |
-
2023
- 2023-08-31 CN CN202322359375.4U patent/CN220668427U/en active Active
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