Safety confluence valve for pilot operated safety valve

Abstract

The invention relates to the technical field of valves, in particular to a safety confluence valve for a pilot operated safety valve, which is characterized in that a pressure tapping hole is communicated with a safety valve cavity, a confluence valve upper cavity is communicated with a pilot control hole, a confluence valve piston cylinder is arranged in a confluence valve lower cavity, and the safety valve cavity is communicated with an inner cavity of the confluence valve piston cylinder; the safety valve cover is mounted on the valve body; the safety valve rod extends into the safety valve cavity; the confluence valve clack is arranged in the confluence valve upper cavity, and a confluence valve spring is arranged between the confluence valve clack and the confluence valve cover; one end of the confluence valve piston rod is connected with the confluence valve clack, the other end of the confluence valve piston rod is matched with an outlet of the confluence valve piston cylinder, and the confluence valve piston rod is provided with a piston part arranged in the confluence valve piston cylinder. The safety valve and the confluence valve are integrated into a whole, and the pressure tapping hole and the pilot control hole are communicated with the pilot safety valve main valve, so that the collection of the inlet pressure of the pilot safety valve main valve and the pilot opening and closing control function of the pilot safety valve main valve under the safe setting pressure can be realized.

Description

Technical Field

[0001] This invention relates to the field of valve technology, specifically to a safety manifold valve for a pilot-operated safety valve. Background Technology

[0002] The safety valves of the pressurizer in the advanced third-generation "Hualong One" pressurized water reactor nuclear power plant have large diameters, high temperatures and pressures, and place higher demands on valve control and reliability. Therefore, pilot-operated safety manifold valves are required to be compact in structure, easy to disassemble and assemble, integrate pressure tapping and control, have adjustable set pressure, signal feedback, multiple redundant control functions (such as dual-redundant automatic control, manual and automatic remote control, and pure manual control), high reliability, and high seismic resistance. Existing pilot-operated safety manifold valves cannot meet these requirements. Summary of the Invention

[0003] In view of the deficiencies of the prior art, the present invention provides a safety manifold valve for a pilot-operated safety valve, which integrates the safety valve and the manifold valve into a whole. It is connected to the main valve of the pilot-operated safety valve through a pressure tap and a pilot control port, which can realize the function of collecting the inlet pressure of the main valve of the pilot-operated safety valve and pilot opening and closing control of the main valve of the pilot-operated safety valve under the safety set pressure.

[0004] To achieve the above objectives, the present invention provides a safety manifold valve for a pilot-operated safety valve, comprising a valve body, a safety valve cover, a safety valve stem, a manifold valve cover, a manifold valve disc, and a manifold valve piston rod; the valve body has a safety valve cavity, a lower manifold valve cavity, and an upper manifold valve cavity; a pressure tap is connected to the safety valve cavity; the upper manifold valve cavity is connected to a pilot control port; a manifold valve piston cylinder is disposed in the lower manifold valve cavity; and the safety valve cavity is connected to the inner cavity of the manifold valve piston cylinder; the safety valve cover is installed on the... The valve body is described above; the safety valve stem passes through the safety valve cover, extends into the safety valve cavity, and is capable of axial displacement relative to the safety valve cover along the safety valve stem; the manifold valve cover is installed on the valve body; the manifold valve disc is located in the upper cavity of the manifold valve, and a manifold valve spring is disposed between the manifold valve disc and the manifold valve cover; one end of the manifold valve piston rod abuts against the manifold valve disc, and the other end cooperates with the outlet of the manifold valve piston cylinder, and the manifold valve piston rod is provided with a piston portion disposed inside the manifold valve piston cylinder.

[0005] Furthermore, a safety valve spring sleeve is fixed to the upper part of the safety valve cover, and a safety valve adjusting screw is screwed onto the upper part of the safety valve spring sleeve; The safety valve stem is fitted with an upper safety valve spring seat and a lower safety valve spring seat. A safety valve spring is disposed between the upper safety valve spring seat and the lower safety valve spring seat. The upper safety valve spring seat abuts against the bottom of the safety valve adjusting screw, and the lower safety valve spring seat abuts against the safety valve stem.

[0006] Furthermore, the safety valve spring sleeve is fixed with a safety valve limit switch seat, and a switch assembly is provided on the upper part of the safety valve limit switch seat. The switch assembly includes a micro switch, which is used to adjust the open and closed positions according to the height and stroke of the safety valve stem.

[0007] Furthermore, the micro switch is wired and connected to the safety valve electrical connector, the safety valve electrical connector is fixed to the safety valve limit switch cover, the safety valve limit switch cover is fixed to the safety valve limit switch seat, and the safety valve electrical connector is a quick-plug sealed structure.

[0008] Furthermore, the safety valve cavity is connected to a first pressure test port, and the first pressure test port is provided with a first safety valve blind flange that is detachably connected to the valve body; The pressure tap is connected to a second pressure test port, and the second pressure test port is provided with a second safety valve blind flange that is detachably connected to the valve body.

[0009] Furthermore, a first spiral wound gasket is provided between the blind flange of the first safety valve and the valve body; a second spiral wound gasket is provided between the blind flange of the second safety valve and the valve body.

[0010] Furthermore, a safety valve adjusting nut is screwed onto the lower part of the safety valve cover. The outer circumference of the safety valve adjusting nut has multiple straight teeth evenly distributed around its periphery. The safety valve adjusting bolt can rotate to adjust the safety valve adjusting nut. The safety valve adjusting nut is threadedly connected to a safety valve adjusting sleeve. Adjusting the safety valve adjusting bolt controls the gap between the safety valve adjusting sleeve and the valve body.

[0011] Furthermore, a safety valve positioning nut is screwed onto the lower part of the safety valve stem to control the opening height of the safety valve discharge.

[0012] Furthermore, a third spiral wound gasket is provided between the manifold valve cover and the valve body.

[0013] Furthermore, a sealing assembly is provided between the safety valve stem and the safety valve cover. The sealing assembly includes a safety valve packing pad and packing stacked from bottom to top, with a safety valve packing pressure plate that is detachably connected to the safety valve cover stacked on top of the packing.

[0014] The beneficial effects of this invention are: by integrating the safety valve and the manifold valve into a whole, and communicating with the main valve of the pilot-operated safety valve through the pressure tapping port and the pilot control port, it is possible to realize the acquisition of the inlet pressure of the main valve of the pilot-operated safety valve and the pilot opening and closing control function of the main valve of the pilot-operated safety valve under the safety set pressure. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of a safety manifold valve for a pilot-operated safety valve according to one embodiment of the present invention; Figure 2 This is a partial cross-sectional view of a safety manifold valve for a pilot-operated safety valve according to an embodiment of the present invention; Figure 3 This is a schematic diagram showing the nameplate location of a safety manifold valve for a pilot-operated safety valve according to one embodiment of the present invention; Figure 4 for Figure 1 A magnified view of part A in the middle; Figure 5 for Figure 1 A magnified view of part B in the middle section; Figure 6 for Figure 1 A magnified view of part C in the middle; Figure 7 This is a rear view of a safety manifold valve for a pilot-operated safety valve according to an embodiment of the present invention; Figure 8 This is a left view of a safety manifold valve for a pilot-operated safety valve according to an embodiment of the present invention; Figure 9 This is a right view of a safety manifold valve for a pilot-operated safety valve according to an embodiment of the present invention; Figure 10 This is a perspective view of a safety manifold valve for a pilot-operated safety valve according to an embodiment of the present invention; Figure 11 for Figure 2 Sectional view of DD; In the picture: 100. Valve body; 110. Safety valve cavity; 111. Pressure tap; 112. First test pressure port; 113. First safety valve blind flange; 114. Second test pressure port; 115. Second safety valve blind flange; 116. First spiral wound gasket; 117. Second spiral wound gasket; 120. Lower cavity of manifold valve; 121. Manifold valve piston cylinder; 122. Manifold valve blind flange; 123. Outlet; 124. Sixth spiral wound gasket; 130. Upper cavity of manifold valve; 131. Pilot control port; 140. Fifth spiral wound gasket; 150. First pin hole; 160. Second pin hole; 170. First bolt through hole; 180. Second bolt through hole. 200. Safety valve cover; 210. Sealing assembly; 211. Safety valve packing gasket; 212. Packing; 213. Safety valve packing pressure plate; 220. Safety valve spring sleeve; 221. Safety valve adjusting screw; 222. Safety valve limit switch seat; 223. Safety valve lock nut. 300. Safety valve stem; 310. Safety valve adjusting sleeve; 320. Safety valve adjusting nut; 330. Safety valve adjusting bolt; 340. Fourth spiral wound gasket; 350. Safety valve positioning nut; 360. Safety valve spring; 361. Upper safety valve spring seat; 362. Lower safety valve spring seat. 400. Manifold valve cover; 410. Manifold valve spring; 420. Third spiral wound gasket. 500. Manifold valve disc, 600. Manifold valve piston rod; 610. Piston section; 700. Switch assembly; 710. Micro switch; 711. First safety valve limit switch bracket; 712. Second safety valve limit switch bracket; 720. Safety valve limit switch cover; 730. Safety valve electrical connector. 800. Manifold valve outlet flange; 810. Seventh spiral wound gasket. 900, nameplate; 910, rivet. Detailed Implementation

[0016] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0017] The advanced third-generation "Hualong One" pressurized water reactor nuclear power plant's pressurizer safety valve has a large diameter, operates at high temperatures and pressures, and places higher demands on valve control and reliability. Therefore, a pilot-operated safety manifold valve is required that simultaneously meet performance requirements such as compact structure, ease of disassembly and assembly, integrated pressure tapping and control, adjustable set pressure, signal feedback, multiple redundant control functions (dual-redundant automatic control, manual and automatic remote control, and purely manual control), high reliability, and high seismic resistance. The pilot-operated safety manifold valve provided by this invention is a pilot-operated pressurizer safety valve that integrates pressure tapping and control in the automatic control loop, features adjustable set pressure, signal feedback, a compact structure, ease of disassembly and assembly, and automatic control.

[0018] See Figure 1 and Figure 2In one embodiment of the present invention, a safety manifold valve for a pilot-operated safety valve is provided, which integrates a safety valve and a manifold valve into a single unit. Figure 1 The left side is the safety valve section, and the right side is the manifold valve section. The two sides share the same valve body 100. They are connected to the main valve of the pilot-operated safety valve (not shown in the figure) only through the pressure tap 111 and the pilot control port 131. Together, they can realize the acquisition of the inlet pressure of the main valve of the pilot-operated safety valve and the pilot opening and closing control function of the main valve of the pilot-operated safety valve under the safety set pressure.

[0019] Specifically, see Figure 1 The diagram shows a structural schematic of a safety manifold valve for a pilot-operated safety valve according to an embodiment of the present invention, including a valve body 100, a safety valve cover 200, a safety valve stem 300, a manifold valve cover 400, a manifold valve disc 500, and a manifold valve piston rod 600.

[0020] Valve body 100 has an opening located at Figure 1 The safety valve chamber 110 on the left side, and located in Figure 1 The lower chamber 120 and upper chamber 130 of the manifold valve on the right side are connected by a pressure tap 111 to the safety valve chamber 110. The upper chamber 130 is connected to a pilot control port 131. A manifold valve piston cylinder 121 is installed inside the lower chamber 120, and the safety valve chamber 110 is connected to the inner cavity of the manifold valve piston cylinder 121. The safety valve cover 200 is installed on the valve body 100. The safety valve stem 300 passes through the safety valve cover 200, extends into the safety valve chamber 110, and can be positioned relative to the safety valve valve... The cover 200 is displaced axially along the valve stem 300 of the safety valve; the manifold cover 400 is installed on the valve body 100; the manifold valve disc 500 is located in the upper cavity 130 of the manifold valve, and a manifold valve spring 410 is arranged between the manifold valve disc 500 and the manifold valve cover 400; one end of the manifold valve piston rod 600 abuts against the manifold valve disc 500, and the other end cooperates with the outlet 123 of the manifold valve piston cylinder 121, and the manifold valve piston rod 600 is provided with a piston part 610 located inside the manifold valve piston cylinder 121.

[0021] The aforementioned pilot-operated safety valve uses pressure tap 111 in the safety manifold to collect the inlet pressure of the main valve of the pilot-operated safety valve. When the pressure rises to the set discharge pressure of the safety valve, the safety valve stem 300 opens, and the pressure enters the inner cavity of the manifold piston cylinder 121 from the safety valve cavity 110, discharging pressure downstream to the manifold valve. As the pressure of the medium discharged from the safety valve to the manifold valve increases, the manifold piston rod 600 moves vertically upward under the action of the medium pressure, thereby pushing the manifold valve disc 500 upward until the force is sufficient to overcome the downward force of the pilot circuit medium on the manifold valve disc 500 and the downward pressure of the manifold valve spring 410, thus opening the manifold valve disc 500. In this way, the pilot circuit medium enters the upper cavity 130 of the manifold valve through the pilot control port 131, and flows together with the medium discharged from the safety valve through the manifold piston cylinder 121 to the outlet 123 of the manifold valve for discharge. This releases pressure on the pilot control circuit of the pilot-operated safety valve main valve, ultimately opening the pilot-operated safety valve main valve. When the safety valve reseats and closes, the pressure inside the manifold piston cylinder 121 decreases. The manifold piston rod 600 and the manifold valve disc 500 then move downwards under their own weight, the downward pressure of the manifold spring 410, and the force of the medium in the pilot control circuit of the pilot-operated safety valve main valve until the manifold valve disc 500 returns to the sealing surface of the valve body 100, forming a seal and ultimately closing the sealing pilot control circuit, thus closing the pilot-operated safety valve main valve to its designated position.

[0022] It should be noted that the valve body 100 is the main component of the safety manifold valve, integrating the safety valve and the manifold valve into a single unit. It connects to the main valve of the pilot-operated safety valve (not shown in the figure) via the pressure tap 111 and the pilot control port 131. For specific settings, please refer to [reference needed]. Figure 7 The valve body 100 of the pilot-operated safety manifold valve is pre-machined with a first pin hole 150 and a second pin hole 160 to facilitate installation and positioning with the pilot-operated safety valve body via mounting pins. The valve body 100 of the pilot-operated safety manifold valve is also machined with a first bolt through hole 170 and a second bolt through hole 180, allowing for easy installation and fixation of the entire safety manifold valve using only bolts, nuts, and anti-loosening washers, and facilitating subsequent disassembly and assembly.

[0023] See also Figure 1 In one embodiment, the safety valve cavity 110 is connected to a first pressure test port 112, and the first pressure test port 112 is provided with a first safety valve blind flange 113 that is detachably connected to the valve body 100; the pressure tap 111 is connected to a second pressure test port 114, and the second pressure test port 114 is provided with a second safety valve blind flange 115 that is detachably connected to the valve body 100.

[0024] It should be noted that the safety manifold valve has a second safety valve blind flange 115 on its side. This second safety valve blind flange 115 can serve as a pressure tapping flange. When it is necessary to test the safety valve pressure, the flange with a pressure tapping port 111 can be replaced at the second safety valve blind flange 115 to test the pressure changes before and after the safety valve. Additionally, after manually isolating the safety valve inlet with a pre-operated isolating valve, a separate external pressure source can be connected to the second safety valve blind flange 115 to test the set pressure and operational performance of the spring-piloted control circuit.

[0025] See Figure 4 Furthermore, in one embodiment, a first spiral wound gasket 116 is provided between the first safety valve blind flange 113 and the valve body 100; a second spiral wound gasket 117 is provided between the second safety valve blind flange 115 and the valve body 100. In a specific embodiment, the first spiral wound gasket 116 is pressed into the sealing groove of the valve body 100 by the first safety valve blind flange 113 through studs, anti-loosening gaskets, and nuts, ensuring sealing performance under different pressure changes and different temperature expansion changes, and the sealing performance is better as the pressure increases. The second spiral wound gasket 117 is pressed into the sealing groove of the valve body 100 by the second safety valve blind flange 115 through studs, anti-loosening gaskets, and nuts, ensuring sealing performance under different pressure changes and different temperature expansion changes, and the sealing performance is better as the pressure increases.

[0026] See also Figure 2 and Figure 4 In one embodiment, the safety valve adjusting sleeve 310 is threadedly connected to the safety valve adjusting nut 320, which is then screwed onto the safety valve cover 200. The safety valve adjusting nut 320 has a circumferentially distributed number of straight teeth. Using an external tool, the safety valve adjusting nut 320 can be rotated and adjusted, causing the safety valve adjusting sleeve 310 to move up and down relative to the safety valve cover 200, ultimately controlling the gap between the safety valve adjusting sleeve 310 and the valve body 100. After adjustment, the safety valve adjusting bolt 330 is screwed in. The safety valve adjusting bolt 330 engages with the straight teeth on the outer side of the locking safety valve adjusting nut 320, locking the position of the safety valve adjusting nut 320, thereby controlling the safety valve's initial discharge pressure and the change in medium pressure to the manifold valve after discharge. The fourth spiral wound gasket 340 is screwed and pressed into the sealing groove of the valve body 100 by the safety valve adjusting bolt 330 to ensure sealing performance requirements.

[0027] See also Figure 4The safety valve stem 300, as the main moving component for safety, has hard alloy 370 welded onto its sealing contact surface with the valve body 100. This surface is also machined with a throttling control fit to ensure normal sealing and discharge performance of the safety valve. The hard alloy welded onto the sealing surface improves its impact resistance, resistance to media erosion, and wear resistance. The safety valve positioning nut 350 is screwed onto the safety valve stem 300. Adjusting the screwing height of the safety valve positioning nut 350 on the valve stem 300 controls the distance between the safety valve positioning nut 350 and the safety valve cover 200, thereby controlling the opening height of the safety valve discharge operation.

[0028] When the safety valve spring 360 is in a compressed state, it presses against the upper safety valve spring seat 361 and the lower safety valve spring seat 362, pushing the safety valve stem 300 towards a closed state. After the safety valve releases pressure, as the medium pressure before the safety valve decreases, the safety valve stem 300 will automatically descend until it closes to the sealing surface of the valve body 100, thus achieving the closure and sealing of the safety valve.

[0029] like Figure 5 As shown, the fifth spiral wound gasket 140 is pressed into the sealing ring groove of the valve body 100 by the safety valve cover 200 through studs, anti-loosening gaskets, and nuts, ensuring the sealing performance of the connection between the safety valve cover 200 and the valve body 100 under different pressure changes and different temperature expansion changes, and the sealing performance is better as the pressure increases.

[0030] See also Figure 1 and Figure 4 In one embodiment, a sealing assembly 210 is provided between the safety valve stem 300 and the safety valve cover 200. The sealing assembly 210 includes a safety valve packing gasket 211 and packing 212 stacked from bottom to top. A safety valve packing pressure plate 213, detachably connected to the safety valve cover 200, is stacked on top of the packing 212. In this embodiment, the safety valve packing gasket 211 and packing 212 are installed between the safety valve stem 300 and the safety valve cover 200, and the safety valve packing pressure plate 213 is fastened to the safety valve cover 200 by studs, anti-loosening washers, and nuts, ensuring the sealing performance between the safety valve stem 300 and the safety valve cover 200 under different pressure changes and different temperature expansion changes.

[0031] like Figure 1As shown, the safety valve spring sleeve 220 is welded to the safety valve cover 200, serving two purposes: protecting and positioning the safety valve spring 360, and providing support and connection. The safety valve adjusting screw 221 is screwed onto the safety valve spring sleeve 220, with its lower part in positioning and pressing contact with the upper safety valve spring seat 361. By adjusting the height of the safety valve adjusting screw 221, the pressing force on the safety valve spring 360 is adjusted, ultimately achieving the adjustment of the set discharge pressure of the safety valve. After the set discharge pressure is set, it can be locked and positioned by the safety valve locking nut 223 to ensure that the set discharge pressure does not change. The upper part of the safety valve spring sleeve 220 is screwed and fixed with a safety valve limit switch seat 222, serving as the basic support for the safety valve switch position signal feedback.

[0032] Furthermore, in conjunction with see Figure 6 A switch assembly 700, including a micro switch 710, is mounted on the upper part of the safety valve limit switch base 222. The micro switch 700 has two positions: an open position switch and a closed position switch. These are clamped together by bolts, flat washers, and nuts via a first safety valve limit switch bracket 711 and a second safety valve limit switch bracket 712. The open and closed positions can be adjusted according to the height and stroke of the safety valve stem 300. The entire assembly is then fixed to the safety valve limit switch cover 720 by hexagonal head screws and anti-loosening washers. The micro switch 710 is wired to the safety valve electrical connector 730. The safety valve electrical connector 730 is a quick-plug sealed structure, facilitating rapid disassembly or installation of the connection wiring. This allows for quick plug-and-play connections to external interfaces while ensuring the connector meets requirements for sealing, insulation, shock resistance, and electromagnetic interference resistance. Similarly, the safety valve electrical connector 730 is fixed to the safety valve limit switch cover 720 by hexagonal head screws and anti-loosening washers. The safety valve limit switch cover 720 is fixed to the safety valve limit switch seat 222 by internal hexagonal head screws and anti-loosening washers.

[0033] The safety valve section of the aforementioned pilot-operated safety valve manifold is equipped with an open switch and a closed switch, which can provide signal feedback on the open / closed position of the safety valve, thereby verifying the conduction and closure status of the main valve control circuit, facilitating subsequent judgment of the opening and closing status of the pilot-operated safety valve main valve.

[0034] See Figure 5The manifold piston cylinder 121 is a major internal component of the manifold valve, positioned within the manifold valve section of the valve body 100 by the manifold blind flange 122. The manifold piston cylinder 121 has guide holes and guide spaces inside and around its periphery, allowing the media discharged from the safety valve and the pilot control circuit to be collected and discharged together at the manifold valve outlet 123. Simultaneously, the manifold blind flange 122 uses studs, anti-loosening gaskets, and nuts to press the sixth spiral wound gasket 124 into the sealing ring groove of the valve body 100, ensuring the sealing performance at the connection between the valve body 100 and the manifold blind flange 122 under different pressure and temperature expansion changes, with the sealing performance improving as the pressure increases.

[0035] See also Figure 5 The seventh spiral wound gasket 810 is pressed into the sealing ring groove of the valve body 100 by studs, anti-loosening gaskets, and nuts from the manifold outlet flange 800. This ensures the sealing performance of the connection between the valve body 100 and the manifold outlet flange 800 under different pressure and temperature expansion changes, and the sealing performance improves with increasing pressure. The manifold outlet flange 800 also serves to position and press the manifold piston cylinder 121 into the inner cavity of the manifold section of the valve body 100.

[0036] In one embodiment, a third spiral wound gasket 420 is provided between the manifold cover 400 and the valve body 100.

[0037] The manifold cover 400 uses studs, anti-loosening washers, and nuts to keep the manifold spring 410 in a compressed state, while simultaneously pressing the third spiral wound gasket 420 into the sealing ring groove of the valve body 100. This ensures the sealing performance of the connection between the valve body 100 and the manifold cover 400 under different pressure changes and different temperature expansion changes, and the sealing performance is better as the pressure increases.

[0038] In addition, the safety manifold valve has a first safety valve blind flange 113 on its side, which can be used as a pressure tapping interface flange. When it is necessary to test the safety valve pressure, the flange can be replaced with a flange with a pressure tapping hole 111 to test the pressure changes before and after the safety valve. Furthermore, after manually isolating the safety valve inlet with a pre-operated isolating valve before the safety valve, a separate external pressure source can be connected to the sealing flange to test the set pressure and operational performance of the spring-operated control circuit. The valve body 100 of the safety manifold valve has a first pin hole 150 and a second pin hole 160 pre-machined to facilitate the installation and positioning of the pins with the pilot-operated safety valve body. The valve body 100 also has a first bolt through hole 170 and a second bolt through hole 180 pre-machined. Through these bolt through holes, bolts, nuts, and anti-loosening washers can be used to install and fix the entire safety manifold valve, facilitating subsequent disassembly and assembly.

[0039] When the aforementioned pilot-operated safety valve operates with a safety manifold valve, if the inlet pressure of the main valve of the pilot-operated safety valve rises to the set discharge pressure of the safety valve, the valve stem 300 of the safety valve trips, and the safety valve automatically opens to discharge pressure to the downstream manifold valve. The set discharge pressure, opening height, and pressure control value of the discharge to the manifold valve can be controlled through an internal adjustment structure. The manifold valve piston rod 600 is installed inside the manifold valve piston cylinder 121. As the pressure of the medium discharged from the safety valve to the manifold valve increases, the manifold valve piston rod 600 moves vertically upward under the action of the medium pressure, thereby pushing the manifold valve disc 500 upward until the force is sufficient to overcome the downward force of the pilot circuit medium on the manifold valve disc 500 and the downward pressure of the manifold valve spring 410, thus opening the manifold valve disc 500. In this way, the pilot circuit medium flows through the manifold valve piston cylinder 121 and merges with the medium discharged from the safety valve to the outlet 123 of the manifold valve for discharge. This releases pressure on the pilot control circuit of the pilot-operated safety valve main valve, ultimately opening the main valve. When the safety valve reseats and closes, the pressure inside the manifold piston cylinder 121 decreases. The manifold piston rod 600 and valve disc 500 then move downwards under their own weight, the downward pressure of the manifold spring 410, and the force of the medium in the pilot control circuit of the pilot-operated safety valve main valve until the valve disc 500 returns to the sealing surface of the valve body 100, forming a seal and ultimately closing the sealed pilot control circuit, thus closing the pilot-operated safety valve main valve. Hard alloy material is welded onto both the valve disc 500 and the sealing surface of the valve body 100 to improve the sealing surface's impact resistance, resistance to media erosion, and wear resistance.

[0040] The safety valve features a compact structure, adjustable set pressure, adjustable opening height, and adjustable control force for the manifold valve. It also has a switch position signal feedback function. Hard alloy is welded to the sealing contact surfaces of the valve stem 300 and valve body 100 to improve wear resistance and resistance to media erosion. A throttling control fit shape is also machined to ensure normal sealing and discharge performance. A pressure tap 111 on one side of the safety valve collects the inlet pressure of the pilot-operated safety valve's main valve, automatically initiating discharge and reseating to close based on pressure changes. The discharged media pressure flows directly into the inner cavity of the manifold valve's piston cylinder 121, indirectly controlling the opening and closing of the manifold valve. When the inlet pressure of the pilot-operated safety valve's main valve rises to the set discharge pressure, the safety valve automatically opens, discharging pressure to the downstream manifold valve. The set discharge pressure, opening height, and pressure control value discharged to the manifold valve can be controlled through an internal adjustment structure.

[0041] The manifold valve is a multi-functional composite valve with a built-in manifold valve piston cylinder 121. The opening and closing of the manifold valve controls the opening and closing of the main valve control circuit, thereby controlling the opening and closing of the pilot-operated safety valve main valve. On one hand, the manifold valve releases the discharge pressure after the safety valve trips through its outlet 123; on the other hand, it utilizes the discharge pressure after the safety valve trips, through the driving force generated by the built-in manifold valve piston cylinder 121, to open the manifold valve disc 500 at the pilot control port 131. This releases the medium pressure in the pilot control circuit of the pilot-operated safety valve main valve piston upper chamber through the manifold valve outlet 123, thus allowing the main valve to open under the different medium pressures in the upper and lower chambers of the piston, and maintain its open state. After the pressure before the main valve of the pilot-operated safety valve decreases to the reseating pressure value of the safety valve, the safety valve reseated and closed. The pressure after the safety valve is discharged and reduced through the outlet 123 of the manifold valve until the manifold valve automatically closes under the combined action of the manifold valve spring 410, the weight of the manifold valve disc 500, and the remaining medium pressure in the pilot control circuit of the main valve piston, thereby controlling the main valve of the pilot-operated safety valve to close.

[0042] The nameplate 900 is fixed to the side of the valve body 100 by rivets 910, marking the valve's relevant parameters and other key information, and forming a complete whole with the entire safety manifold valve. The structure is compact, the spatial layout is reasonable, and the overall effect is harmonious and beautiful.

[0043] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0044] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0045] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0046] In this invention, unless otherwise explicitly specified and limited, "above" or "below" a second feature can mean that the first and second features are in direct contact, or that they are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of a second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" a second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature. It should be noted that when an element is referred to as "fixed to" or "set on" another element, it can be directly on the other element or there may be an intermediate element present. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element present. The terms "vertical," "horizontal," "above," "below," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible embodiments.

Claims

1. A safety manifold valve for pilot-operated safety valves, characterized in that: include The valve body has a safety valve cavity, a lower manifold valve cavity, and an upper manifold valve cavity. The pressure tap is connected to the safety valve cavity. The upper manifold valve cavity is connected to the pilot control hole. A manifold valve piston cylinder is installed in the lower manifold valve cavity. The safety valve cavity is connected to the inner cavity of the manifold valve piston cylinder. Safety valve cover, installed on the valve body; The safety valve stem passes through the safety valve cover, extends into the safety valve cavity, and is capable of axial displacement relative to the safety valve cover along the safety valve stem. The manifold valve cover is installed on the valve body; A manifold valve disc is located in the upper cavity of the manifold valve, and a manifold valve spring is disposed between the manifold valve disc and the manifold valve cover; The manifold valve piston rod has one end abutting against the manifold valve disc and the other end cooperating with the outlet of the manifold valve piston cylinder. The manifold valve piston rod is equipped with a piston portion disposed inside the manifold valve piston cylinder.

2. The safety manifold valve for a pilot-operated safety valve according to claim 1, characterized in that: A safety valve spring sleeve is fixed to the upper part of the safety valve cover, and a safety valve adjusting screw is screwed onto the upper part of the safety valve spring sleeve; The safety valve stem is fitted with an upper safety valve spring seat and a lower safety valve spring seat. A safety valve spring is disposed between the upper safety valve spring seat and the lower safety valve spring seat. The upper safety valve spring seat abuts against the bottom of the safety valve adjusting screw, and the lower safety valve spring seat abuts against the safety valve stem.

3. The safety manifold valve for a pilot-operated safety valve according to claim 2, characterized in that: The safety valve spring sleeve is fixed with a safety valve limit switch seat. A switch assembly is provided on the upper part of the safety valve limit switch seat. The switch assembly includes a micro switch, which is used to adjust the open and closed positions according to the height and stroke of the safety valve stem.

4. The safety manifold valve for a pilot-operated safety valve according to claim 3, characterized in that: The micro switch is wired and connected to the safety valve electrical connector. The safety valve electrical connector is fixed to the safety valve limit switch cover. The safety valve limit switch cover is fixed to the safety valve limit switch seat. The safety valve electrical connector is a quick-plug sealed structure.

5. The safety manifold valve for a pilot-operated safety valve according to claim 1 or 2, characterized in that: The safety valve cavity is connected to a first pressure test port, and the first pressure test port is provided with a first safety valve blind flange that is detachably connected to the valve body. The pressure tap is connected to a second pressure test port, and the second pressure test port is provided with a second safety valve blind flange that is detachably connected to the valve body.

6. The safety manifold valve for a pilot-operated safety valve according to claim 5, characterized in that: A first spiral wound gasket is provided between the blind flange of the first safety valve and the valve body; a second spiral wound gasket is provided between the blind flange of the second safety valve and the valve body.

7. The safety manifold valve for a pilot-operated safety valve according to claim 1 or 2, characterized in that: The lower part of the safety valve cover is screwed with a safety valve adjusting nut. The outer circumference of the safety valve adjusting nut has multiple straight teeth evenly distributed around its periphery. The safety valve adjusting bolt can rotate to adjust the safety valve adjusting nut. The safety valve adjusting nut is threadedly connected to a safety valve adjusting sleeve. Adjusting the safety valve adjusting bolt controls the gap between the safety valve adjusting sleeve and the valve body.

8. The safety manifold valve for a pilot-operated safety valve according to claim 1 or 2, characterized in that: The lower part of the safety valve stem is screwed with a safety valve positioning nut to control the opening height of the safety valve discharge.

9. The safety manifold valve for a pilot-operated safety valve according to claim 1 or 2, characterized in that: A third spiral wound gasket is provided between the manifold valve cover and the valve body.

10. The safety manifold valve for a pilot-operated safety valve according to claim 1 or 2, characterized in that: A sealing assembly is provided between the safety valve stem and the safety valve cover. The sealing assembly includes a safety valve packing pad and packing stacked from bottom to top, and a safety valve packing pressure plate that is detachably connected to the safety valve cover is stacked on top of the packing.

Images