Low pressure safety valve with auxiliary full opening function

Abstract

The application discloses a low-pressure safety valve with an auxiliary full-opening function, which comprises a valve body, a valve seat, a valve clapper assembly, a valve rod, a lower guide sleeve assembly and an upper guide sleeve assembly; the low-pressure safety valve further comprises a top rod and a nut sleeve, the nut sleeve is sleeved on the outside of the top rod, the top rod is threadedly connected with the nut sleeve through the cooperation of helical teeth and helical grooves, the outer wall of the nut sleeve is connected with the inner wall of the valve seat in an integrated manner through a plurality of connecting rods which are uniformly distributed in a circumferential direction, a plurality of turbine blades which are uniformly distributed in a circumferential direction are integrally formed on the outer wall of the top rod above the nut sleeve, a supporting ring is sleeved on the outside of the plurality of turbine blades, and the outer end of each turbine blade is connected with the inner side wall of the supporting ring in an integrated manner; the application can provide sufficient additional lift for the valve clapper assembly under the condition of low pressure difference and low flow rate, help the valve clapper assembly to fully open, and improve the flow capacity and the stability of action of the valve.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of low-pressure safety valves, in particular to a low-pressure safety valve with auxiliary full-opening function. BACKGROUND

[0002] A low-pressure safety valve is a valve that can ensure that the space of a storage tank is isolated from the atmosphere within a certain pressure range and can be communicated with the atmosphere (breathing) when the pressure exceeds or is lower than the range, and its function is to prevent the destruction of the storage tank due to overpressure or vacuum, and to reduce the evaporation loss of the stored liquid.

[0003] A low-pressure safety valve is used to maintain the pressure balance of a storage tank, and its principle is to use the weight of the valve disc assembly and the counterweight disc to control the exhaust positive pressure and the suction negative pressure of the storage tank. When the pressure in the tank rises to the operating positive pressure of the low-pressure safety valve, the valve opens, and the gas escapes from the low-pressure safety valve outlet, so that the pressure in the tank no longer continues to rise. When the pressure in the tank decreases to the operating negative pressure of the low-pressure safety valve, the atmosphere outside the tank will open the valve disc assembly of the suction valve, so that the outside air enters the tank, so that the pressure in the tank no longer continues to decrease, and the pressure balance between the inside and outside of the tank is achieved to protect the storage tank.

[0004] Unlike conventional high-pressure safety valves, since the pressure of the storage tank can be lower than atmospheric pressure or higher than atmospheric pressure, the low-pressure safety valve often appears in the form of a valve group: a breathing valve group, the principles of the exhaust valve and the suction valve are basically the same, only the installation direction is opposite, and the following description takes the exhaust valve as an example:

[0005] A conventional safety valve is generally provided with a backflush disc, which makes the ejected gas flow turn to obtain a larger lifting force of the valve disc assembly, reaches the full opening height, and adjusts the discharge pressure and the opening and closing pressure difference by means of the backflush disc adjusting ring, and its action characteristic is two-stage action, the discharge capacity is large and the action is stable, but the low-pressure safety valve cannot obtain much lifting force due to the low medium pressure difference and slow medium flow rate. SUMMARY

[0006] In view of the deficiencies of the prior art, the present application provides a low-pressure safety valve with auxiliary full-opening function, which can provide sufficient additional lifting force to the valve disc assembly under low pressure difference and low flow rate, help the valve disc assembly to fully open, and improve the flow capacity and stability of the valve.

[0007] The low-pressure safety valve with auxiliary full-opening function of the application comprises a valve body, a valve seat, a valve clapper assembly, a valve rod, a lower guide sleeve assembly and an upper guide sleeve assembly; the valve seat is fixed on the inner bottom of the valve body and is sealed with the valve body through an O-ring; the upper guide sleeve assembly and the lower guide sleeve assembly are distributed in an up-down manner; the outer edge of the upper guide sleeve assembly and the outer edge of the lower guide sleeve assembly are both fixed with the upper end of the valve body; the valve clapper assembly is arranged above the valve seat and the edge of the valve clapper assembly abuts against the edge of the valve seat; the lower end of the valve rod is fixed with the middle part of the upper end of the valve clapper assembly; the upper end of the valve rod is movably arranged in the lower guide sleeve assembly and the upper guide sleeve assembly; the low-pressure safety valve further comprises a top rod and a nut sleeve; the top rod is arranged below the middle part of the valve clapper assembly; the nut sleeve is arranged outside the top rod; the inner wall of the nut sleeve is provided with a helical groove with a rectangular cross section; the outer wall of the top rod is provided with a helical tooth with a rectangular cross section; the shape of the helical tooth is matched with the shape of the helical groove; the top rod is threadedly connected with the nut sleeve through the cooperation of the helical tooth and the helical groove; the outer wall of the nut sleeve is connected with the inner wall of the valve seat through a plurality of connecting rods which are uniformly distributed in a circumferential direction; the outer wall of the top rod above the nut sleeve is integrally formed with a plurality of turbine blades which are uniformly distributed in a circumferential direction; the outer part of the plurality of turbine blades is provided with a support ring; the outer end of each turbine blade is integrally connected with the inner side wall of the support ring.

[0008] Through the above structure, when the turbine blades drive the top rod to rotate to move the top rod upward relative to the nut sleeve, the top rod can push the valve clapper assembly upward, that is, the application can provide sufficient additional lift for the valve clapper assembly under low pressure difference and low flow rate, help the valve clapper assembly to fully open, and improve the flow capacity and stability of the valve.

[0009] The low-pressure safety valve with auxiliary full-opening function of the application, wherein the upper end of the top rod is in a pointed end structure; through the above structure, the friction between the top rod and the valve clapper assembly can be reduced, so that the top rod can be more reliably and smoothly rotated relative to the valve clapper assembly and the nut sleeve, and the top rod can more smoothly lift the valve clapper assembly.

[0010] The low-pressure safety valve with auxiliary full-opening function of the application, wherein the outer wall of the upper end of the top rod and the lower surface of the valve clapper assembly are both sprayed with a polytetrafluoroethylene coating; through the above structure, the friction between the top rod and the valve clapper assembly can be further reduced, so that the top rod can be more reliably and smoothly rotated relative to the valve clapper assembly and the nut sleeve, and the top rod can more smoothly lift the valve clapper assembly; in addition, the mutual freezing of the top rod and the valve clapper assembly at low temperature can be avoided.

[0011] The low-pressure safety valve with auxiliary full opening function of the application, wherein the outer wall of the helical tooth and the inner wall of the helical groove are sprayed with a polytetrafluoroethylene coating; after adopting this structure, the friction between the helical tooth and the helical groove can be further reduced, so that the top rod can be more reliable and more smoothly relative to the nut sleeve rotation, and the top rod can be more smoothly lifted to the valve disc assembly; in addition, the mutual freezing of the top rod and the nut sleeve at low temperature can be avoided.

[0012] The low-pressure safety valve with auxiliary full opening function of the application, wherein the upper end surface of the valve disc assembly is fixed with a counterweight plate; through the setting of the counterweight plate, the sealing specific pressure of the valve disc assembly and the valve seat can be adjusted.

[0013] The low-pressure safety valve with auxiliary full opening function of the application, wherein the connecting rod is provided with three, and the turbine blade is provided with five; after adopting this structure, when the turbine blade drives the top rod to rotate, the resonance can be avoided. BRIEF DESCRIPTION OF DRAWINGS

[0014] The drawings described herein are used to provide further understanding of the application, and form a part of the application, the illustrative embodiments of the application and the description thereof are used to explain the application, and do not constitute improper limitation on the application. In the drawings:

[0015] Figure 1 It is a perspective structural schematic diagram of the application;

[0016] Figure 2 It is a sectional structural schematic diagram of the application when closing;

[0017] Figure 3 It is a sectional structural schematic diagram of the application when closing; Figure 2 It is a sectional structural schematic diagram of the application when closing;

[0018] Figure 4 It is a sectional structural schematic diagram of the application when closing;

[0019] Figure 5 It is a sectional structural schematic diagram of the application when closing;

[0020] Figure 6 It is a sectional structural schematic diagram of the application when closing; Figure 5 It is a sectional structural schematic diagram of the application when closing; DETAILED DESCRIPTION

[0021] Many practical details are set forth in the following description to provide a thorough understanding of the application. However, it will be apparent to those skilled in the art that the application can be practiced without many of these details. In other instances, well-known structures and components are not described in detail or are presented in simple block diagram form in order to avoid obscuring the application. As used herein, the term "including" has the same meaning as "comprising" and "including" is to be construed as specifying the presence of stated features or steps without excluding the presence or addition of one or more other features or steps.

[0022] In addition, the description herein, such as with respect to "first" and "second", is merely intended to different components or steps described in the same technical terms and should not be construed as indicating or implying that their relative importance or a specific number of technical features is in any way defined. Therefore, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions of various embodiments can be combined with each other, but it must be based on the realization of ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection required by the application.

[0023] As Figures 1-6The low-pressure safety valve with auxiliary full-opening function shown in the application comprises a valve body 1, a valve seat 2, a valve clapper assembly 3, a valve rod 4, a lower guide sleeve assembly 5 and an upper guide sleeve assembly 6; the valve seat 2 is fixed on the inner bottom of the valve body 1 and is sealed with the valve body 1 through an O-shaped ring 7; the upper guide sleeve assembly 6 and the lower guide sleeve assembly 5 are distributed in an up-down manner; the outer edge of the upper guide sleeve assembly 6 and the outer edge of the lower guide sleeve assembly 5 are both fixed with the upper end of the valve body 1; the valve clapper assembly 3 is arranged above the valve seat 2 and the edge of the valve clapper assembly 3 abuts against the edge of the valve seat 2; the lower end of the valve rod 4 is fixed with the middle part of the upper end of the valve clapper assembly 3; the upper end of the valve rod 4 is movably arranged in the lower guide sleeve assembly 5 and the upper guide sleeve assembly 6; the low-pressure safety valve further comprises a top rod 8 and a nut sleeve 9; the top rod 8 is located below the middle part of the valve clapper assembly 3; the nut sleeve 9 is arranged outside the top rod 8; the inner wall of the nut sleeve 9 is provided with a rectangular cross-section spiral groove 91; the outer wall of the top rod 8 is provided with a rectangular cross-section spiral tooth 81; the shape of the spiral tooth 81 is matched with the shape of the spiral groove 91; the top rod 8 is threadedly connected with the nut sleeve 9 through the cooperation of the spiral tooth 81 and the spiral groove 91; the outer wall of the nut sleeve 9 is integrally connected with the inner wall of the valve seat 2 through a plurality of circumferentially uniformly distributed connecting rods 92; the outer wall of the top rod 8 above the nut sleeve 9 is integrally formed with a plurality of circumferentially uniformly distributed turbine blades 82; the outer part of the plurality of turbine blades 82 is provided with a support ring 83; the outer end of each turbine blade 82 is integrally connected with the inner side wall of the support ring 83.

[0024] When the turbine blades 82 drive the top rod 8 to rotate to move the top rod 8 upward relative to the nut sleeve 9, the top rod 8 is used to upwardly lift the valve clapper assembly 3.

[0025] The top rod 8 is provided with a pointed end structure; through the adoption of the structure, the friction between the top rod and the valve clapper assembly can be reduced, so that the top rod can be more reliably and smoothly rotated relative to the valve clapper assembly and the nut sleeve, and the top rod can more smoothly lift the valve clapper assembly.

[0026] The outer wall of the upper end of the top rod 8 and the lower surface of the valve clapper assembly 3 are both sprayed with a polytetrafluoroethylene coating; through the adoption of the structure, the friction between the top rod and the valve clapper assembly can be further reduced, so that the top rod can be more reliably and smoothly rotated relative to the valve clapper assembly and the nut sleeve, and the top rod can more smoothly lift the valve clapper assembly; in addition, the mutual freezing of the top rod and the valve clapper assembly at low temperature can be avoided.

[0027] The outer wall of the helical tooth 81 and the inner wall of the helical groove 91 are sprayed with a polytetrafluoroethylene coating; after adopting this structure, the friction between the helical tooth and the helical groove can be further reduced, so that the ejector rod can be more reliable and more smoothly relative to the nut sleeve rotation, and the ejector rod can be more smoothly lifted to the valve assembly; in addition, the mutual freezing of the ejector rod and the nut sleeve at low temperature can be avoided.

[0028] The upper end surface of the valve assembly 3 is fixed with a counterweight plate 31; through the setting of the counterweight plate, the sealing specific pressure of the valve assembly and the valve seat can be adjusted.

[0029] The connecting rod 92 is provided with three, and the turbine blade 82 is provided with five; after adopting this structure, when the turbine blade drives the ejector rod to rotate, the resonance condition can be avoided.

[0030] When the storage tank is overpressure to make the valve assembly partially open, the medium in the storage tank can flow through the turbine blade and be discharged to the outside of the valve body through the gap between the valve assembly and the valve seat, since the medium from the storage tank flows through the turbine blade, the medium from the storage tank can drive the turbine blade, the support ring and the ejector rod to rotate, when the ejector rod rotates, the ejector rod can move upward relative to the nut sleeve and push the valve assembly, until the valve assembly is completely pushed open; when the medium in the storage tank is discharged, under the action of gravity, the ejector rod, the turbine blade and the support ring can move downward and reset, and the valve assembly can also move downward and reset under the action of gravity.

[0031] The above is only an embodiment of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application should be included in the scope of claims of the present application.

Claims

1. A low-pressure safety valve with auxiliary full-opening function, comprising a valve body (1), a valve seat (2), a valve disc assembly (3), a valve stem (4), a lower guide sleeve assembly (5), and an upper guide sleeve assembly (6); the valve seat (2) is fixed on the inner bottom of the valve body (1) and the valve seat (2) is sealed to the valve body (1) by an O-ring (7); the upper guide sleeve assembly (6) and the lower guide sleeve assembly (5) are arranged vertically; the outer edges of the upper guide sleeve assembly (6) and the lower guide sleeve assembly (5) are both fixed to the upper end of the valve body (1); the valve disc assembly (3) is disposed above the valve seat (2) and the edge of the valve disc assembly (3) abuts against the edge of the valve seat (2); the lower end of the valve stem (4) is fixed to the middle of the upper end of the valve disc assembly (3); the upper end of the valve stem (4) is movably inserted through the lower guide sleeve assembly (5) and the upper guide sleeve assembly (6), characterized in that: The low-pressure safety valve also includes a push rod (8) and a nut sleeve (9). The push rod (8) is located below the middle of the valve disc assembly (3). The nut sleeve (9) is fitted over the push rod (8). The inner wall of the nut sleeve (9) is provided with a helical groove (91) with a rectangular cross-section. The outer wall of the push rod (8) is provided with helical teeth (81) with a rectangular cross-section. The shape of the helical teeth (81) matches the shape of the helical groove (91). The push rod (8) is threadedly connected to the nut sleeve (9) through the cooperation of the helical teeth (81) and the helical groove (91). The outer wall of the nut sleeve (9) is connected through... A number of circumferentially evenly distributed connecting rods (92) are connected to the inner wall of the valve seat (2). A number of circumferentially evenly distributed turbine blades (82) are integrally formed on the outer wall of the push rod (8) located above the nut sleeve (9). A support ring (83) is sleeved on the outside of the turbine blades (82). The outer end of each turbine blade (82) is connected to the inner side wall of the support ring (83). When the turbine blades (82) drive the push rod (8) to rotate so that the push rod (8) moves upward relative to the nut sleeve (9), the push rod (8) is used to push the valve disc assembly (3) upward.

2. The low-pressure safety valve with auxiliary full-opening function according to claim 1, characterized in that, The upper end of the top rod (8) is a pointed structure.

3. The low-pressure safety valve with auxiliary full-opening function according to claim 2, characterized in that, The outer wall of the upper end of the top rod (8) and the lower surface of the valve assembly (3) are coated with polytetrafluoroethylene.

4. The low-pressure safety valve with auxiliary full-opening function according to any one of claims 1-3, characterized in that, The outer wall of the spiral teeth (81) and the inner wall of the spiral groove (91) are coated with polytetrafluoroethylene.

5. The low-pressure safety valve with auxiliary full-opening function according to claim 1, characterized in that, A counterweight plate (31) is fixed at the middle of the upper end face of the valve assembly (3).

6. The low-pressure safety valve with auxiliary full-opening function according to claim 1, characterized in that, The connecting rod (92) has three parts, and the turbine blade (82) has five blades.

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