A safety relief valve

Abstract

A safety valve according to the present invention comprises a valve body through which fluid flowing in through a valve nozzle is discharged through a discharge portion; a valve disc assembly provided inside the valve body and shielding the end of the valve nozzle; a valve cover provided on the upper side of the valve body and providing a supply path for operating pressure for opening and closing operation of the valve disc assembly; a valve stem connected to the valve disc assembly inside the valve body; and a disc opening and closing means that accommodates at least a portion of the valve stem and allows the valve stem to move up or down by varying its length according to the operating pressure and the pressure of the fluid flowing in through the valve nozzle, thereby causing the valve disc assembly to move up or down. The disc opening and closing means includes an upper partition plate that shields the upper part of the valve body so as to separate a pressure space on the upper side of the discharge portion; a bellows that is airtightly coupled to the upper partition plate on one side and airtightly shielded on the other side by a lower shielding plate on the other side; and a bellows that penetrates the upper partition plate and the lower shielding plate. A disc center bolt is included to connect the exposed end of the valve stem to the valve disc assembly, and a pressure regulating hole is further formed in the upper partition plate to allow operating pressure to enter and exit into the airtight space inside the bellows. According to the present invention, the safety valve can be manufactured more easily, and has the advantage of reducing leakage and enabling more stable, repetitive operation.

Description

Technology Field

[0001] The present invention relates to a safety valve applied to a hydraulic system to prevent accidents caused by overpressure. Background Technology

[0003] Generally, safety relief valves are installed in pipes serving as passages for fluids related to positive pressure or negative pressure, or in pressure tanks or pressure vessels that store and utilize a constant pressure, to protect the facilities and surrounding systems.

[0004] That is, the above safety valve is configured to operate when the pressure of the equipment exceeds the set pressure to prevent excessive pressure from being generated in the hydraulic system, and can be configured as a pilot-operated type linked with a pilot valve when precise control is required by adjusting the degree of opening.

[0005] For example, FIG. 1 is a drawing showing an embodiment of a safety valve according to the prior art, and the illustrated safety valve is configured as a pilot-operated type including a main body (11) communicating with a gas storage tank, a diaphragm valve that opens and closes the inlet of the main body (11), and a pilot valve (40) that operates the diaphragm valve.

[0006] Looking at this in detail, the main body (11) is provided with a nozzle (12) that is drawn in from the lower side at a predetermined height toward the internal space (A) to form an inlet for high-pressure gas.

[0007] The nozzle (12) provides an inflow path for high-pressure gas flowing into the space (A) and is selectively connected to the space (A) by the diaphragm valve.

[0008] That is, the diaphragm valve is seated on the top of the nozzle (12) to selectively block the gas outflow path, and to this end, includes the following components.

[0009] First, a diaphragm retainer (24) having a high-pressure gas inlet / outlet hole (21) formed at the top of the main body (11) and a cover (22) coupled to the top of the diaphragm retainer (24) are provided.

[0010] Additionally, a diaphragm (23) is interposed between the diaphragm retainer (24) and the cover (22), and a diaphragm disk (29) is further provided on the upper surface of the diaphragm (23).

[0011] A stem (25) that is vertically connected is further provided in the center of the diaphragm disk (29), and a disk (26) that opens and closes the inlet of the nozzle (12) is provided at the end of the stem (25), and a seat (27) is further provided at the bottom of the disk (26), and a seat cover (28) is further provided at the bottom of the seat (27).

[0012] The diaphragm valve configured as described above receives operating pressure through the pilot valve (40) provided at the top of the cover (22), thereby enabling the opening and closing of the upper inlet of the nozzle (12).

[0013] Meanwhile, the diaphragm valve having such characteristics is configured such that the disc (26) and the seat (27) rise and fall to open and close the inlet of the nozzle (12) according to the difference between the pressure of the fluid applied to the disc (26) through the inlet of the nozzle (12) from the gas storage tank and the pressure of the fluid applied to the disc (26) through the pilot valve (40) connected to the connecting pipe (31) from the gas storage tank.

[0014] That is, the safety valve operated using the diaphragm (23) as described above is opened and closed by changing the position of the disk (26) covering the upper inlet of the nozzle (12) as the diaphragm (23), which is molded into a film shape, changes shape in response to pressure.

[0015] However, the diaphragm (23) with the above-mentioned function has poor moldability, making it difficult to implement the shape, and has the problem of having poor durability as it is manufactured in a thin form.

[0016] In addition, the diaphragm (23) made in the shape of a film has the problem that it is difficult to match the concentricity of the connection part when cutting and installing the inner / outer parts, and that the opening operation is not smooth when the weight of the disc is large. Prior art literature

[0018] (Patent Document 0001) KR 10-2024-0145807 A The problem to be solved

[0019] The object of the present invention is to provide a safety valve in which the opening and closing of a disc is performed by a disc opening and closing means including a welded bellows.

[0020] Another objective of the present invention is to provide a safety valve in which the valve disc assembly and the disc opening / closing means are joined by fastening the valve stem and the disc center bolt, thereby allowing for an alignment error even when the axial direction of the stem is not perpendicular to the planar direction of the nozzle, so that the disc assembly is seated parallel to the nozzle.

[0021] Another objective of the present invention is to provide a safety valve in which the protruding position of the nozzle end is located below the center of the discharge section, thereby enabling smoother fluid discharge. means of solving the problem

[0023] A safety valve according to the present invention comprises a valve body through which fluid flowing in through a valve nozzle is discharged through a discharge portion; a valve disc assembly provided inside the valve body and shielding the end of the valve nozzle; a valve cover provided on the upper side of the valve body and providing a supply path for operating pressure for opening and closing operation of the valve disc assembly; a valve stem connected to the valve disc assembly inside the valve body; and a disc opening and closing means that accommodates at least a portion of the valve stem and allows the valve stem to move up or down by varying its length according to the operating pressure and the pressure of the fluid flowing in through the valve nozzle, thereby causing the valve disc assembly to move up or down. The disc opening and closing means includes an upper partition plate that shields the upper part of the valve body so as to separate a pressure space on the upper side of the discharge portion; a bellows that is airtightly coupled to the upper partition plate on one side and airtightly shielded on the other side by a lower shielding plate on the other side; and a bellows that penetrates the upper partition plate and the lower shielding plate. The disc center bolt connecting the exposed end of the valve stem to the valve disc assembly is included, and the upper partition plate is further characterized by having a pressure regulating hole formed therein to allow operating pressure to enter and exit into the airtight space inside the bellows.

[0024] The above bellows is characterized by being formed by welding together a plurality of molded bodies, each formed by cutting and corrugating a plate material to have a size corresponding to the upper end of the valve nozzle.

[0025] The above valve nozzle is positioned below the horizontal extension line of the center of the discharge section formed on one side of the valve body, and the bellows is characterized in that, when fully contracted, the position of the lower shielding plate is positioned above the horizontal extension line of the center of the discharge section.

[0026] The above-described disc center bolt is characterized in that a portion of it penetrates the valve disc assembly and is fitted into a bolt connection formed at the bottom of the valve stem.

[0027] The lower shielding plate and the valve disc assembly are characterized by being spaced apart by at least the length of the bolt connection portion.

[0028] The upper section plate is further characterized by having a stem guide for accommodating at least a portion of the upper part of the valve stem to guide the movement path of the valve stem. Effects of the invention

[0029] The safety valve according to the present invention has the advantage of maintaining stable performance by changing the diaphragm, which is difficult to shape and handle when manufacturing a safety valve with a flexible diaphragm structure, into a disc opening and closing means including a welded bellows having constant formability of steel.

[0030] That is, in the case of a safety valve with a diaphragm made of a flexible film, there is a problem of low durability (tearing, deformation, etc.) during the manufacturing, handling, and operation of the diaphragm, but the welded bellows according to the present invention is formed by laminating and welding a plurality of molded bodies that are corrugated to correspond to the edge of the valve nozzle, thereby improving durability compared to the diaphragm structure and having excellent elasticity, so the axial compression length can be increased.

[0031] In addition, in the case of a safety valve with a diaphragm, it is difficult to achieve concentricity during internal / external cutting and internal assembly of the main body; however, in the disc opening / closing means according to the present invention, the fastening structure of the valve stem coupled to the valve disc assembly is connected via a bush pin coupling or a universal coupling structure.

[0032] Therefore, even when the planar directions of the valve stem and the nozzle are not perpendicular, alignment error is allowed, which is a feature that allows the disc assembly to be stably seated on the top of the valve nozzle.

[0033] Furthermore, the welded bellows according to the present invention can easily adjust its length by additionally stacking a plurality of corrugated molded bodies as needed.

[0034] Therefore, by positioning the top of the valve nozzle protruding into the valve body at a lower location than the center of the discharge port on one side of the valve body, it has the advantage of reducing resistance during fluid discharge, thereby enabling smoother pressure release.

[0035] In addition, reducing the height of the valve nozzle as described above can reduce the cost of raw materials required for nozzle molding, which is relatively expensive, and offers the advantage of easily adapting to different types of fluids by varying the material of the corrugated molded body. Brief explanation of the drawing

[0037] FIG. 1 is a drawing showing an embodiment of a safety valve according to the prior art. FIG. 2 is a drawing showing an embodiment of a safety valve according to the present invention. FIG. 3 is an exploded perspective view showing the detailed structure of a safety valve according to one embodiment of the present invention. FIG. 4 is a drawing for explaining the detailed structure of a disk opening and closing means, which is a key component of the present invention. Fig. 5 is a cross-sectional view of section AA of Fig. 2. FIG. 6 is a drawing for explaining the flow path opening and closing structure of a safety valve according to the present invention. FIG. 7 is a diagram illustrating the process of opening a disc according to a change in pressure acting on a safety valve according to the present invention. Specific details for implementing the invention

[0038] The safety valve according to the present invention is applied to a hydraulic system and configured to prevent accidents caused by overpressure.

[0039] Hereinafter, some embodiments of the safety valve according to the present invention will be described in detail with reference to exemplary drawings. It should be noted that in assigning reference numerals to the components of each drawing, the same components are given the same reference numeral whenever possible, even if they are shown in different drawings. Furthermore, in describing the embodiments of the present invention, if it is determined that a detailed description of related known components or functions would hinder understanding of the embodiments of the present invention, such detailed description is omitted.

[0040] In addition, terms such as first, second, A, B, (a), (b), etc., may be used when describing the components of the embodiments of the present invention. These terms are used merely to distinguish the components from other components, and the essence, order, or sequence of the components is not limited by the terms used.

[0041] First, FIG. 2 is a drawing showing an embodiment of a safety valve according to the present invention. The safety valve (100) according to the present invention is configured such that an overpressure fluid flowing in through a valve nozzle (400) into an internal space formed by a valve body (200) and a valve cover (600) is discharged through a discharge portion (240), and the operating pressure for opening and closing the valve nozzle (400) can be provided through a fluid connection port (620) provided in the valve cover (600).

[0042] For a more detailed explanation, FIG. 3 shows an exploded perspective view to show the detailed structure of a safety valve according to one embodiment of the present invention, FIG. 4 shows a drawing to explain the detailed structure of a disc opening and closing means which is a key component of the present invention, and FIG. 5 shows a cross-sectional view of part AA of FIG. 2.

[0043] Referring to these drawings, the valve body (200) is formed with an open shape at the top, bottom, and one side, and the valve nozzle (400) is inserted into the lower opening and positioned to protrude a predetermined height into the internal space.

[0044] The upper side of the valve body (200) is shielded by the valve cover (600), and the valve cover (600) is provided with a fluid connection port (620) so that fluid can enter and exit the internal space of the valve body (200).

[0045] One open side of the valve body (200) is a discharge section (240) through which the overpressure fluid introduced through the valve nozzle (400) is discharged. In this embodiment, the upper end of the valve nozzle (400) is positioned below the horizontal imaginary extension line of the center of the pipe diameter of the discharge section (240) to reduce discharge resistance when discharging the overpressure fluid, thereby enabling smoother discharge.

[0046] Meanwhile, the valve nozzle (400) arranged as described above has its end shielded by a valve disc assembly (900) provided inside the valve body (200).

[0047] To this end, the valve disc assembly (900) may be configured to include a valve disc and a valve seat, and is connected to a valve stem (700) that moves up or down inside the valve body (200).

[0048] And, the valve stem (700) connected to the valve disc assembly (900) is connected to a disc opening / closing means (800) whose length is variable by the operating pressure supplied for the opening / closing operation of the valve disc assembly (900) and the pressure of the fluid flowing in through the valve nozzle (400).

[0049] The above-mentioned disc opening and closing means (800) comprises an upper partition plate (820) that shields the upper part of the valve body so as to separate the pressure space above the discharge portion (240), a bellows (840) that is airtightly connected to the upper partition plate (820) on one side and airtightly shielded to the lower shielding plate (860) on the other side, and a disc center bolt (880) that connects the end of the valve disc assembly (900) and the valve stem (700).

[0050] In this embodiment, the upper partition plate (820) is interposed between the upper end of the valve body (200) and the valve cover (600), thereby partitioning the upper pressure space inside the valve cover (600) and the lower pressure space inside the valve body.

[0051] Additionally, the upper portion of the bellows (840) may be joined to the upper partition plate (820) by means such as welding, and an upper sealing member (842) may be further provided to reinforce airtightness performance.

[0052] A lower shielding plate (860) may be attached to the bottom of the bellows (840) by means such as welding to form an airtight internal space, and a lower sealing member (844) may be further provided to reinforce the airtight performance.

[0053] The bellows (840), which is formed as a sealed structure as described above, is formed by welding together a plurality of molded bodies that are cut and corrugated to have a size corresponding to the top of the valve nozzle.

[0054] The plurality of molded bodies constituting the above bellows (840) can be manufactured by rolling, press forming, roll forming, etc., various metal plates such as aluminum, steel, and stainless steel.

[0055] That is, the safety valve (100) according to the present invention can be easily applied to various fluids by changing the material of the molded body constituting the bellows (840).

[0056] Meanwhile, the bellows (840) provided as described above is extended in length by the operating pressure flowing into the upper pressure space and is contracted in length by the pressure of the fluid flowing in through the valve nozzle (400).

[0057] To this end, a pressure control hole (822) is formed in the upper partition plate (820) so that operating pressure can enter and exit into the bellows (840), and a plurality of pressure control holes (822) may be arranged symmetrically with respect to the center of the upper partition plate (820) within a range corresponding to the internal space of the bellows (840).

[0058] Additionally, a stem guide (720) is further provided at the center of the upper section plate (820) to guide the movement path when the valve stem (700) moves up and down.

[0059] The above stem guide (720) is divided into a head portion and a guide portion, and the guide portion can be fitted into a stem insertion hole (722) formed at the center of the upper section plate (820), and can be fixed by a fastening member such as a bolt while the head portion is seated on the upper surface of the upper section plate (820).

[0060] The above guide portion may be formed as a tubular body sized to accommodate the entire outer diameter of the valve stem (700) so that the valve stem (700) is accommodated inside and a predetermined length path guide can be provided, and a sealing member such as an O-ring may be further provided between the stem guide (720) and the upper partition plate (820) to maintain airtightness.

[0061] The valve stem (700) is provided in a sealed space inside the bellows (400), with one end accommodated inside the stem guide (720) and the other end exposed toward the valve disc assembly (900) by penetrating the lower shielding plate (860).

[0062] The end of the valve stem (700) exposed as described above can be connected to a disc center bolt (880) that penetrates the valve disc and valve seat from the lower side of the valve disc assembly (900) and is partially exposed to the upper side.

[0063] To this end, a bolt connection part (700a) of a corresponding shape is provided at the end of the valve stem (700) so that the end of the disc center bolt (880) is fitted thereon.

[0064] Meanwhile, in this embodiment, the disc center bolt (880) has a pin shape in which the diameter of the upper part is expanded by a predetermined size compared to the body, and the lower part is formed to include a spiral that rotates and penetrates the valve disc assembly (900). Additionally, the bolt connection part (700a) is formed in the shape of a bushing corresponding to the upper part of the pin shape of the disc center bolt (880) so that it can be fastened and received in a press-fit manner.

[0065] That is, in this embodiment, the valve stem (700) and the valve disc assembly (900) are connected by a bushed pin coupling method using a disc center bolt (880) of the shape described above, so that even if the axis of the valve stem (700) is not perpendicular to the upper horizontal direction of the valve nozzle (400), the alignment of the upper part of the valve nozzle (400) and the valve disc assembly (900) for shielding it can be stably achieved.

[0066] In addition, when the valve stem (700) is connected to the valve disc assembly (900) using the disc center bolt (880) having the structure as described above, a gap is formed between the valve disc assembly (900) and the lower shielding plate (860) with a length corresponding to the length of the bolt connection part (700a) and the fastening part of the disc center bolt (880), so that the disc opening / closing means (800) can be protected from a relatively high temperature and high pressure fluid.

[0067] Meanwhile, the valve stem (700) can be coupled with the valve disc assembly (900) in a universal coupling structure including a cross shaft and a fork.

[0068] In addition, even in such a connection structure, even if the axial direction of the valve stem (700) is not perpendicular to the horizontal direction of the valve nozzle (400), the valve disc assembly (900), which is separately configured from the valve stem (700), is fitted and rotatable, so that it can be stably positioned on the upper part of the valve nozzle (400) within a predetermined range of tolerance.

[0070] The operation of a safety valve (100) having the above-mentioned structure will be explained below with reference to the attached drawings.

[0071] FIG. 6 illustrates a diagram for explaining the flow path opening and closing structure of a safety valve according to the present invention, and FIG. 7 illustrates a diagram for explaining the disc opening process according to a change in pressure acting on the safety valve according to the present invention.

[0072] First, referring to FIGS. 6a and FIGS. 7a, the operating pressure of the fluid flowing into the bellows (840) through the pressure control hole (822) is adjusted to have a pressure greater than that of the fluid flowing into the valve nozzle (400) in order to maintain the valve nozzle (400) in a sealed state.

[0073] That is, the upper pressure applied to the lower shielding plate (860) in the internal airtight space of the bellows (840) corresponds to the lower pressure applied to the valve disc assembly (900) through the valve nozzle (400), and at this time, the maximum extension length (L1) of the bellows (840) is maintained.

[0074] In the above state, as shown in FIG. 7b, when the upper pressure is released and the internal pressure of the bellows (840) decreases, the lower pressure applied to the valve disc assembly (900) forms a higher pressure than the upper pressure applied to the lower shielding plate (860) in the airtight space inside the bellows (840), and as shown in FIG. 6b and FIG. 7c, the valve disc assembly (900) is pushed upward by the lower pressure and opens.

[0075] And, at this time, the operating pressure inside the bellows (840) is discharged through the pressure control hole (822) of the upper partition plate (820), and the bellows (840) is compressed and deformed to a minimum contraction length (L2).

[0076] That is, the safety valve (100) according to the present invention repeatedly expands and contracts due to the difference between the operating pressure applied to the lower shielding plate (860) by flowing into the bellows (840) and the excessive pressure applied to the valve disc assembly (900) through the valve nozzle (400), thereby discharging the excessive pressure, and as a plurality of molded bodies are welded to form it, stable discharge of excessive pressure can be achieved without tearing or deformation even under repeated operating conditions.

[0077] In addition, the welded bellows (840) according to the present invention can be formed by stacking and welding a plurality of molded bodies that are corrugated to correspond to the protruding height of the valve nozzle (400) as described above, and through this, the position of the valve nozzle (400) is formed at a position lower than the center of the discharge part (240), thereby reducing discharge resistance when excessive pressure is discharged, so that smoother discharge can be achieved.

[0078] The above description is merely an example for implementing a safety valve that enables the opening and closing of a disc in conjunction with length adjustment based on the variable pressure of the internal space of a welded bellows. The present invention is not limited to the above-described example, and the technical spirit of the present invention extends to the scope in which any person with ordinary knowledge in the technical field to which the present invention belongs can implement it by making various modifications without departing from the gist of the invention as claimed in the following patent claims. Explanation of the symbols

[0080] 100........ Safety valve 200........ Valve body 240........ Discharge section 400........ Valve nozzle 600........ Valve cover 620........ Fluid connection port 700........ Valve stem 700a....... Bolt connection section 720........ Stem guide 722........ Stem insertion hole 800........ Disc opening / closing means 820........ Bellows upper shielding plate 822........ Pressure regulating hole 840........ Bellows 842........ Upper sealing member 844........ Lower sealing member 860........ Bellows lower shielding plate 880........ Disc center bolt 900........ Valve disc assembly

Claims

Claim 1 A valve body through which fluid flowing in through a valve nozzle is discharged through a discharge portion; a valve disc assembly provided inside the valve body and shielding the end of the valve nozzle; a valve cover provided on the upper side of the valve body and providing a supply path for operating pressure for opening and closing operation of the valve disc assembly; and a valve stem connected to the valve disc assembly inside the valve body. The disc opening / closing means includes a valve stem that accommodates at least a portion of the valve stem and allows the valve stem to move up or down by varying its length according to the operating pressure and the pressure of the fluid flowing in through the valve nozzle, thereby causing the valve disc assembly to move up or down. The disc opening / closing means includes an upper partition plate that shields the upper part of the valve body so as to separate a pressure space above the discharge portion, a bellows in which one side is hermetically coupled to the upper partition plate and the other side is hermetically shielded by a lower shielding plate, and a sealing member is provided at each of the upper and lower ends, and a disc center bolt that connects the end of the valve stem exposed through the upper partition plate and the lower shielding plate to the valve disc assembly. A plurality of pressure control holes are formed in the upper partition plate and are symmetrically arranged with respect to the center of the upper partition plate so that the operating pressure enters and exits the hermetically sealed space inside the bellows. The disc center bolt has a pin shape in which the diameter of the upper part is expanded by a predetermined size compared to the body, and the lower part rotates and penetrates the valve disc assembly. A safety valve characterized by being formed to include a spiral, and having a bushing-shaped bolt connection formed at the bottom of the valve stem such that the pin-shaped portion of the disc center bolt is received in an interference fit manner, so that the valve stem and the valve disc assembly are coupled in a bushing pin coupling manner, and even if the planar direction of the valve stem and the valve nozzle are not perpendicular due to the coupling structure, an alignment error is allowed so that the disc assembly can be stably seated on the top of the valve nozzle. Claim 2 A safety valve according to claim 1, wherein the bellows is formed by laminating and welding a plurality of molded bodies, each formed by cutting and corrugating one or more metal plates selected from aluminum, steel, and stainless steel to have a size corresponding to the top of the valve nozzle. Claim 3 A safety valve according to claim 1, wherein the valve nozzle is positioned below the horizontal extension line of the center of the discharge portion formed on one side of the valve body, and the bellows is characterized in that, when fully contracted, the position of the lower shielding plate is positioned above the horizontal extension line of the center of the discharge portion. Claim 4 A safety valve according to claim 1, wherein the lower shielding plate and the valve disc assembly are spaced apart at a distance corresponding to the fastening length of the bolt connection part and the disc center bolt, and configured such that the disc opening / closing means is protected from high temperature and high pressure fluid by said distance. Claim 5 delete Claim 6 delete

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