Pressure release valve

Abstract

FIELD: residual pressure relief valve.SUBSTANCE: valve located between a source of pressurized fluid and a hydraulic or pneumatic actuator and designed to provide the ability to relieve residual pressure, in particular for use in systems for measuring the quantity and quality of oil and petroleum products, for example in a ball valve. The pressure relief valve has a body consisting of three parts: the upper valve cover, the cup and the lower valve cover. In the upper valve cover, the inlet and outlet channels are made perpendicular and connected by a cavity; a cage with holes is also installed in the cavity, in which a spool valve with a rod is located so that, during reciprocating movement, they have the ability to open and close access from the inlet channel to the cavity. A spring is placed in the glass, with one end of the spring resting on the rod and the other on the adjusting screw. The adjusting screw is located in the glass and the lower cover of the valve.EFFECT: facilitation of the assembly and repair of a pressure relief valve by creating a detachable housing and increase of the operational reliability by using a design of a safety valve with the ability to adjust the opening pressure, in which the risks of distortion are minimized.9 cl, 3 dwg

Description

[0001] Technical field

[0002] The present invention relates to a residual pressure relief valve located between a pressurized fluid source and a hydraulic or pneumatic actuator and designed to allow the release of residual pressure. Specifically, it is suitable for use in systems for measuring the quantity and quality of oil and petroleum products, such as in a ball valve.

[0003] Technology Level

[0004] Ball valves with a decompression function are known from the prior art, where a standard ball valve with a circulation channel and a manual drive is supplemented by an upper piston chamber with a relief hole and a piston kinematically connected through a connecting rod with a “punch holder - die holder” unit and a fixed stage clamp, which ensures a controlled release of pressure from the cavity.

[0005] Safety relief valves (SRV) can also be used to relieve excess pressure from a ball valve. The designs and types are described in detail in The Safety Relief Valve Handbook by Marc Hellemans (Access mode, access date 11 / 21 / 2025: https: / / inspectapedia.com / plumbing / Safety-Relief-Valve-Handbook-Hellemans.pdf).

[0006] A similar design of operator controlled pressure relief valves is published on pages 33-34.

[0007] A prior art residual pressure relief valve is known from patent RU 2565117, international application WO 2013 / 035877, priority date 14.03.2013. It comprises a valve body provided with first and second channels, as well as a third channel connected to them. A converter consisting of a pin and a cam ring consisting of two separate half rings with inclined grooves is located between the control element and the body. A disadvantage of this solution is the structural complexity and reduced reliability during field operation. The presence of a motion converter (pin + cam ring consisting of two half rings with inclined grooves) introduces a complex contact profile and relative sliding, which increases the requirements for manufacturing accuracy and lubrication compared to a spring-screw assembly with a stem and spool.A two-piece cam ring must be mated and secured with concentricity and matching groove profiles; misalignment leads to runout, uneven force, and jerky operation. Cam profiles and pin tracks are sensitive to abrasion and media deposits; contamination causes sticking and increases response hysteresis, whereas a classic spring-rod-spool assembly tolerates contamination more easily and is less expensive to clean. Assembling a half-ring assembly involves additional operations (positioning, clamping, clearance control), which lengthens the assembly cycle and complicates field repairability.

[0008] A pressure relief valve (variants) and a valve assembly comprising the said valve according to patent application BR102018068373, priority date 01.12.2017, which has a housing with an inlet port and at least one outlet port, and a plunger configured to move between a first position in which said plunger blocks said at least one outlet port, and a second position in which it does not block; and wherein the plunger has a diameter-to-length ratio of less than approximately 1:2. This solution is structurally the closest and is accepted as an analogue. The disadvantage of this solution is the fact that the surface of the housing serves as a guide for the rod and spring, which complicates the processing process. There is no guide inside the spring.Also, due to the lack of a plunger and spring guide, mechanical impact and / or spring breakage can cause the plunger to jump off the inlet port, leading to misalignment within the cavity and failure to seal the inlet channel. The proposed solution addresses this issue with a cage housing the spool and piston. Jumping is also possible in the prototype. The proposed solution also includes a rod inside the spring, and its position is further secured with spring clips.

[0009] The technical result of the present invention is to facilitate the assembly and repair of a pressure relief valve by creating a dismountable body consisting of three main elements and to increase the reliability of operation by using a design of a safety valve with the ability to adjust the opening pressure, in which the risks of distortion are minimized by using guides and fixing elements: a cage, a rod and spring clamps.

[0010] Essence Revealed

[0011] The technical result is achieved by using a pressure relief valve, the body of which consists of three main elements fixed together: the upper valve cover, the cup and the lower valve cover; in the upper valve cover, the inlet and outlet channels are made perpendicular to each other and are connected by a cavity, a cage with holes is also installed in the cavity, in which a spool valve with a stem is placed so that during reciprocating movement the stem pulls the spool valve and it is possible to open and close access from the inlet channel to the cavity, a spring is placed in the cup, wherein one edge of the spring rests on the stem, and the other on the adjusting screw, the adjusting screw is located in the cup and the lower valve cover.

[0012] The fluid from the inlet channel presses on the spool through the stem, which presses on the spring, causing it to contract and open the inlet channel. The pressurized fluid enters the chamber and is discharged through the outlet channels. When the pressure returns to normal, the valve returns to the closed position. Importantly, the stem and spool pass inside the cage, preventing distortion, and the spring is secured with spring clips. In the event of a malfunction, the disassemblable design of the valve body allows for individual component replacement.

[0013] The difference between the claimed invention and the prototype is the use of a prefabricated housing structure and the use of guide and fixing elements of the structure.

[0014] Brief description of drawings

[0015] Fig. 1 - Design of pressure relief valve;

[0016] Fig. 2 - 3D model of the valve in section, front view;

[0017] Fig. 3 - Valve design options: with one outlet channel (left) and with two outlet channels (right), where

[0018] 1 - Upper valve cover;

[0019] 2 - glass;

[0020] 3 - lower valve cover;

[0021] 4 - fastening;

[0022] 5 - input channel;

[0023] 6 - output channel;

[0024] 7 - cavity;

[0025] 8 - cell;

[0026] 9 - spool;

[0027] 10 - rod;

[0028] 11 - spring;

[0029] 12 - spring clamps;

[0030] 13 - Adjusting screw

[0031] 14 - tongue and groove fastening with seal.

[0032] Implementation

[0033] The pressure relief valve has a valve body housing all internal components. The valve body consists of three parts: the upper valve cover 1, the bowl 2, and the lower valve cover 3, which are arranged in series and secured with a fastener 4. In the illustrated embodiment, studs are used as fasteners. In the preferred embodiment, the body parts are designed with a tongue-and-groove fastening system with seals 14.

[0034] The top cover of valve 1 is intended for connection to a device requiring pressure relief, such as a ball valve, via fasteners 4. An inlet channel 5 is provided in the top cover of the valve, through which a pressurized medium enters the valve. An outlet channel 6 is provided perpendicular to the inlet channel, designed to discharge the medium received from inlet channel 5. Channels 5 and 6 intersect in cavity 7. In the presented embodiments, there may be one, two, or several outlet channels 6, evenly distributed throughout the top cover of valve 1. The number of outlet channels is selected in accordance with the requirements of the operating system to which the valve is attached.

[0035] A cylindrical cage 8 with openings for passing the medium through the cylinder opening coaxially with the inlet valve is installed in cavity 7. Cage 8 is a cylinder with openings, inside which a spool 9 moves, which pulls a rod 10. The cage serves as a guide element for the spool 9, ensuring precise movement and centering of the parts inside the upper cover of the valve body 1. Cage 8 firmly fixes the positions of the elements installed in it and minimizes displacements. Spool 9 and rod 10 are installed in cage 8 so that they have the ability to translate inside the cage 8. In the closed position, under normal pressure, the spool blocks the inlet channel 5. Spool 9 performs the function of the shut-off element of the safety valve, which, when the opening pressure is reached, moves downward, releasing excess pressure through the outlet channel 6.

[0036] Stem 10 is fixed to spool 9 at one end, while the other extends into cup 2 and rests on spring clamps 12. It also extends within spring 11, providing additional centering and protection, into adjusting screw 13 and the lower valve cover 3, which limits its travel. Valve stem 10 is movable within the valve body under the pressure of the operating medium, controlling the position of spool 9.

[0037] Bearer 2 supports spring 11 and other internal valve components, simultaneously protecting them from environmental influences. Bearer 2 is connected to the upper valve cover and the lower valve cover. Spring 11 regulates the closing force of spool 9, setting the pressure threshold at which the valve begins to operate. Spring 11 regulates the valve opening pressure, allowing the pressure relief valve to be adjusted to operating parameters. One end of the spring rests on stem 10, and the other on adjusting screw 13. The spring also has spring retainers 12 on one or both ends for improved fixation and reduced risk of distortion and breakage.

[0038] Adjusting screw 13 changes the preload of spring 11, thereby adjusting the opening pressure of inlet channel 5. Lower valve cover 3 prevents contaminants from entering the pressure relief valve and preventing leakage of the working fluid. It also serves as a travel limiter for piston rod 10.

[0039] The device works as follows:

[0040] To relieve excess pressure, the pressure relief valve is connected to the housing of the source of fluid under pressure by means of a fastener (studs), connecting through the inlet channel 5 in the upper cover of the valve 1. In the case of the “closed” position under normal operating pressure, the inlet channel 5 is blocked by a spool 9 at the entrance to the cavity 7. In the cavity 7, a cage 8 with a spool 9 is installed, which is driven by the action of the pressure of the working medium coming from the channel 5 and goes into the “open” position of the valve.

[0041] Spring 11 is installed with a pre-load, which is adjusted by adjusting screw 13. It keeps the pressure relief valve closed until the pressure of the working medium exceeds the compression force of spring 11.

[0042] When the pressure is exceeded, the spool 9 shifts, opening access for the medium from the inlet channel 5 to the cavity 7, in which the outlet channels 6 are located for discharging excess medium, reducing the pressure.

[0043] When the pressure exceeds the limit, the pressure relief valve opens, and its spool 9, driven by stem 10, shifts, allowing excess fluid to exit through inlet channel 5 into cavity 7 and then through outlet channels 6 into the external environment. The movement is centered by cage 8; stem 10 passes through adjusting screw 13, spring clamps 12, spring 11, and cage 8, centering the valve and transmitting the movement. Adjusting screw 13 sets the force of spring 11.

[0044] The pressure relief valve automatically closes when the pressure returns to normal, and seals in the tongue-and-groove housing elements (14) ensure a tight seal. Cage (8) and stem (10) secure and guide the valve. This maintains optimal pressure and protects the system from overload.

[0045] Thus, the pressure relief valve automates the release of excess pressure, allows for effective control of the working fluid flow, minimizing plug damage, distortion, and jamming in the valve structure, thereby increasing the reliability of the pressure relief valve. The body, consisting of three main elements fixed together, facilitates assembly and repair, as it allows disassembly of only the part of the valve where the breakdown occurred.

Claims

1. A pressure relief valve comprising a housing provided with an inlet and at least one outlet channel, a spring with spring clips and an adjusting screw, a valve stem that locks and opens the channel are housed in the housing, characterized in that the valve housing consists of three parts: an upper valve cover, a cup and a lower valve cover; in the upper valve cover, the inlet and outlet channels are made perpendicularly and are connected by a cavity, a cage with openings is also installed in the cavity, in which a spool valve with a stem is placed so that during reciprocating movement they have the ability to open and close access from the inlet channel to the cavity, a spring is placed in the cup, wherein one edge of the spring rests on the stem, and the other - on the adjusting screw, the adjusting screw is placed in the cup and the lower valve cover.

2. A pressure relief valve according to paragraph 1, characterized in that the parts of the valve are secured to each other by fasteners.

3. A pressure relief valve according to paragraph 2, characterized in that the parts of the valve are secured together with studs.

4. A pressure relief valve according to paragraph 2, characterized in that the valve parts are made with a tongue and groove fastening.

5. A pressure relief valve according to paragraph 4, characterized in that a seal is additionally placed in the tongue and groove fastening.

6. A pressure relief valve according to paragraph 1, characterized in that spring clamps are additionally placed in the cup.

7. A pressure relief valve according to paragraph 6, characterized in that the spring clips are located on both sides of the spring.

8. A pressure relief valve according to paragraph 6, characterized in that the spring retainer is placed between the rod and the spring.

9. The pressure relief valve according to paragraph 6, characterized in that the spring retainer is placed between the adjusting screw and the spring.

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