Differential pressure balanced valve

Abstract

The application belongs to the field of differential pressure type balance valve design and relates to a differential pressure type balance valve, which comprises an upstream flange, a downstream flange, a valve body, a sealing ring, a valve clack, a spring seat, a spring and an adjusting screw; the downstream flange is located above the upstream flange and coaxially butts against the upstream flange; the axes of the upstream flange and the downstream flange are both provided with a medium channel; the sealing ring is arranged at the butt joint of the upstream flange and the downstream flange; the valve body is a hollow cylindrical structure; the valve body is axially and vertically installed on the upper surface of the sealing ring; the valve clack, the spring seat, the spring and the adjusting screw are all arranged in the inner cavity of the valve body; the valve clack is arranged at the top of the sealing ring; the spring seat is arranged at the top of the valve clack; the spring is axially and vertically arranged at the top of the spring seat; the adjusting screw is arranged at the top of the spring, and the outer wall of the adjusting screw is threadedly connected with the inner wall of the valve body; the differential pressure type balance valve provided by the application is applied to high working pressure and high back pressure working conditions and can ensure good sealing performance under an extremely small pressure difference of 0.65 MPa.

Description

Technical Field

[0001] This invention belongs to the field of differential pressure balancing valve design, and in particular, a differential pressure balancing valve. Background Technology

[0002] BDO (1,4-butanediol) is an important organic chemical and fine chemical raw material. Currently, my country's main BDO production process adopts the Reppe method, which primarily uses acetylene and formaldehyde as raw materials, and hydrogenates them to BDO under the catalysis of copper oxide supported on SiO2. The main characteristics of this method are high pressure requirements; the hydrogenation unit pressure is generally above 27 MPa, and the catalyst is not separated. In the Reppe method BDO production unit, multiple pipelines in the hydrogenation unit require a type of relief valve called a "differential pressure balancing valve," primarily to balance the pressure difference across the valve.

[0003] Differential pressure balancing valves differ from conventional safety valves. Because they operate under high working pressure and high back pressure conditions, they need to maintain a seal under a very small pressure difference. Due to pipeline pressure fluctuations and the need for frequent opening and closing during process operations, especially during the initial start-up phase, differential pressure balancing valves have emerged as a solution.

[0004] Under the aforementioned harsh operating conditions, differential pressure balancing valves need to meet the requirements of opening and closing pressure difference ≤10%Ps (set pressure) and overpressure ≤10%Ps. In addition, since differential pressure balancing valves operate under high pressure conditions for a long time and are not convenient to disassemble, it is necessary to ensure that their materials meet the operating conditions, their mechanical properties are stable, and their structural design is compatible with the pipeline design. Summary of the Invention

[0005] The technical problem solved by this invention is to overcome the shortcomings of the prior art and propose a differential pressure balancing valve that is applied to high working pressure and high back pressure conditions, and achieves good sealing performance under extremely small pressure difference of 0.65MPa.

[0006] To solve the above-mentioned technical problems, the solution of the present invention is as follows:

[0007] A differential pressure balancing valve includes an upstream flange, a downstream flange, a valve body, a sealing ring, a valve disc, a spring seat, a spring, and an adjusting screw. The upstream flange is vertically oriented axially. The downstream flange is located above the upstream flange and coaxially connected to it. Both the upstream and downstream flanges have media channels along their axes. The sealing ring is positioned at the connection point of the upstream and downstream flanges, and its position corresponds to the media channels of both flanges. The valve body is a hollow cylindrical structure. The valve body is vertically mounted axially on the upper surface of the sealing ring. The valve disc, spring seat, spring, and adjusting screw are all housed within the inner cavity of the valve body. The valve disc is positioned on top of the sealing ring. The spring seat is positioned on top of the valve disc. The spring is vertically oriented axially on top of the spring seat. The adjusting screw is positioned on top of the spring, and its outer wall is threaded to the inner wall of the valve body.

[0008] The aforementioned differential pressure balancing valve also includes a lock nut and two O-rings. The lock nut is fitted onto the outer wall of the adjusting screw and is located at the top of the valve body. After the adjusting screw and the valve body are adjusted to the correct relative position, the lock nut locks the valve in place. One O-ring is located at the junction of the lower surface of the sealing ring and the upstream flange, while the other O-ring is located at the junction of the upper surface of the sealing ring and the downstream flange.

[0009] In the aforementioned differential pressure balancing valve, the sealing ring has a cylindrical structure; a cylindrical valve body groove is formed at the center of the upper surface of the sealing ring to accommodate the valve body and the valve disc in the valve body cavity; a pipe is coaxially formed at the bottom of the valve body groove; the pipe is connected to the medium passage of the upstream flange.

[0010] In the aforementioned differential pressure balancing valve, a stepped protrusion is provided at the connection between the top of the pipeline and the valve body groove; the sidewall of the stepped protrusion is an inclined wall; the stepped protrusion enables the coaxial alignment of the pipeline and the valve disc; both the upper and lower surfaces of the sealing ring are provided with annular grooves, and each annular groove corresponds to the embedding of an O-ring to achieve sealing with the upstream flange and the downstream flange.

[0011] In the aforementioned differential pressure balancing valve, the valve disc has a columnar structure; the outer wall of the valve disc contacts the inner wall of the valve body; grooves are uniformly formed along the circumference of the outer wall of the valve disc, and the grooves are axially connected along the valve disc to allow the medium to pass through; after the circumferential grooves are formed, the axial cross-section of the valve disc has a gear-shaped structure.

[0012] In the aforementioned differential pressure balancing valve, a conical groove is provided at the center of the upper surface of the valve disc, which is used to align with the spring seat; a stepped groove is provided at the center of the lower surface of the valve disc; the valve disc is aligned with the sealing ring through the cooperation of the stepped groove and the stepped protrusion.

[0013] In the aforementioned differential pressure balancing valve, the diameter of the inner wall of the stepped groove is larger than the diameter of the outer wall of the stepped protrusion, thereby enabling the medium to flow out through the gap between the outer wall of the stepped protrusion and the side wall of the stepped groove.

[0014] In the aforementioned differential pressure balancing valve, the spring seat is a hollow cylindrical structure; a ball head is provided at the bottom of the spring seat; the ball head cooperates with the conical groove to achieve alignment; a venting channel is provided at the top of the spring seat; and balancing holes are uniformly arranged circumferentially on the sidewall of the venting channel.

[0015] In the aforementioned differential pressure balancing valve, the working process is as follows:

[0016] External medium enters the pipeline through the medium passage of the upstream flange and contacts the lower surface of the valve disc. When the thrust generated by the medium on the lower surface of the valve disc overcomes the weight of the valve disc, the weight of the spring seat, the weight of the spring, and the friction between the outer wall of the valve disc and the inner wall of the valve body, the medium pushes the valve disc and the spring seat upward, compressing the spring. The valve disc separates from the sealing ring. The medium flows out through the gap between the outer wall of the stepped protrusion and the side wall of the stepped groove, and enters the inner cavity of the valve body through the groove. Subsequently, the medium enters the discharge passage through the balance hole, realizing communication with the medium passage of the downstream flange, achieving pressure relief, and balancing the pressure difference between the upstream and downstream flanges.

[0017] During the continuous release of medium into the downstream flange medium channel, when the combined force of the internal pressure of the valve body and the spring force is greater than the medium thrust, the spring seat is pushed to drive the valve disc back down until the valve disc is pressed back against the valve body groove of the sealing ring.

[0018] In the aforementioned differential pressure balancing valve, the medium is a mixture of hydrogen and water vapor; the medium is rapidly released by the reaction force generated by the sidewall of the stepped groove on the flowing medium; when the pressure difference between the upstream flange and the downstream flange is greater than or equal to 0.65 MPa, the differential pressure balancing valve starts to release pressure.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] (1) In this invention, the upstream and downstream flanges are fixed with a sealing ring by bolts and nuts for flange sealing. The sealing ring has grooves on its upper and lower surfaces and an O-ring is built in for sealing, resulting in good flange sealing performance. The valve seat and sealing ring are integrated into a single design. During normal pipeline operation, the valve seat and valve disc are tightly closed to ensure good sealing performance.

[0021] (2) The present invention adopts an integrated design of guide structure and valve disc, avoiding problems such as connection form, fit clearance and guide length between guide structure and valve disc when the design is split; the valve disc side surface has a groove for discharging medium, and the part of the valve disc without groove that contacts the valve body is the guide surface. While meeting the discharge volume, the contact area between the guide surface and the valve body is increased as much as possible, and the surface roughness and fit length of the guide surface and the valve body mating surface are improved.

[0022] (3) The spring seat of the present invention directly transmits the spring force to the force-bearing surface of the valve disc, reducing the possibility of misalignment of the force during transmission, ensuring uniform force on the valve disc, improving the stability of the differential pressure balance valve, and is suitable for frequent opening conditions.

[0023] (4) The sealing ring sealing structure designed in this invention, the O-ring sealing type can ensure that the differential pressure balance valve has good sealing performance. Under the inlet pressure ≤90%Ps, the valve sealing performance meets the index requirements in GB / T 12243-2021 and API 527; the overpressure ≤10%Ps, the reseating pressure ≤10%Ps, and the discharge capacity meets the design requirements. Attached Figure Description

[0024] Figure 1 This is a cross-sectional view of the overall structure of the differential pressure balancing valve of the present invention;

[0025] Figure 2 This is a schematic diagram of the sealing ring structure of the present invention;

[0026] Figure 3 This is a top view of the valve disc of the present invention;

[0027] Figure 4 This is a side sectional view of the valve disc of the present invention;

[0028] Figure 5 This is a schematic diagram of the spring seat of the present invention.

[0029] In the picture:

[0030] 1-Upstream flange; 2-Downstream flange; 3-Valve body; 4-Sealing ring; 5-Valve disc; 6-Spring seat; 7-Spring; 8-Adjusting screw; 9-Lock nut; 10-O-ring;

[0031] 41-Valve body groove; 42-Pipeline; 43-Stepped protrusion; 44-Annular groove;

[0032] 51-Groove; 52-Conical groove; 53-Stepped groove; 54-Side wall;

[0033] 61-Ball head; 62-Drainage channel; 63-Balance hole. Detailed Implementation

[0034] The present invention will be further described below with reference to the embodiments.

[0035] This invention provides a differential pressure balancing valve for use under high operating pressure and high back pressure conditions. This valve ensures good sealing performance even with a very small pressure difference of 0.65 MPa. The differential pressure balancing valve is used in the hydrogenation unit pipeline of the Reppe process for BDO production. It balances the pressure difference across the pipeline. When the upstream pressure becomes overpressured due to valve malfunction, a portion of the medium in the pipeline is released downstream through the differential pressure balancing valve, thus preventing overpressure.

[0036] Differential pressure balancing valve, such as Figure 1 As shown, the valve body specifically includes an upstream flange 1, a downstream flange 2, a valve body 3, a sealing ring 4, a valve disc 5, a spring seat 6, a spring 7, an adjusting screw 8, a lock nut 9, and two O-rings 10. The upstream flange 1 is vertically oriented axially. The downstream flange 2 is located above the upstream flange 1 and coaxially connected to it. Both the upstream flange 1 and the downstream flange 2 have media channels along their axes. The sealing ring 4 is located at the connection point of the upstream flange 1 and the downstream flange 2, and its position corresponds to the media channels of both flanges. The valve body 3 is a hollow cylindrical structure. The valve body 3 is vertically mounted axially on the upper surface of the sealing ring 4. The valve disc 5, spring seat 6, spring 7, and adjusting screw 8 are all located within the inner cavity of the valve body 3. The valve disc 5 is located on top of the sealing ring 4. The spring seat 6 is located on top of the valve disc 5. The spring 7 is vertically oriented axially on top of the spring seat 6. The adjusting screw 8 is located on top of the spring 7, and its outer wall is threaded to the inner wall of the valve body 3. The locking nut 9 is fitted onto the outer wall of the adjusting screw 8 and is located on the top of the valve body 3. After the relative position of the adjusting screw 8 and the valve body 3 is adjusted to the correct position, the locking nut 9 is used to lock the valve body. One O-ring 10 is located at the joint between the lower surface of the sealing ring 4 and the upstream flange 1, and the other O-ring 10 is located at the joint between the upper surface of the sealing ring 4 and the downstream flange 2.

[0037] Differential pressure balancing valves are welded to upstream and downstream pipelines via flanges. Depending on their function, they can be divided into three parts: a flange for connecting upstream and downstream pipelines, a sealing ring, and a built-in relief device including the valve body, valve disc, spring, spring seat, adjusting screw, lock nut, O-ring, bolt, and nut. When the upstream medium pressure reaches the set pressure point, the valve disc opens accurately. The medium flows through the sealing surfaces of the valve disc and sealing ring into the valve body cavity, filling the entire area. It then enters the relief channel through the balancing hole on the spring seat and is discharged downstream into the pipeline. When the combined force of the pressure in the valve body cavity and the spring force exceeds the lift force of the medium, the valve disc begins to fall back to the valve seat sealing surface, closing the seal and ultimately achieving the purpose of balancing the pressure difference between the two ends of the pipeline.

[0038] The sealing ring 4 is a column segment structure, as shown in the figure. Figure 2As shown, a cylindrical valve body groove 41 is opened at the center of the upper surface of the sealing ring 4 to place the valve body 3 and the valve disc 5 in the inner cavity of the valve body 3; a pipe 42 is coaxially opened at the bottom of the valve body groove 41; the pipe 42 is connected to the medium channel of the upstream flange 1.

[0039] A stepped protrusion 43 is provided at the connection between the top of the pipe 42 and the valve body groove 41; the side wall of the stepped protrusion 43 is an inclined wall; the pipe 42 and the valve disc 5 are aligned and aligned coaxially through the stepped protrusion 43; the upper and lower surfaces of the sealing ring 4 are provided with annular grooves 44, and each annular groove 44 is embedded with an O-ring 10 to achieve sealing with the upstream flange 1 and the downstream flange 2.

[0040] like Figure 3 As shown, valve disc 5 is a columnar structure; the outer wall of valve disc 5 is in contact with the inner wall of valve body 3; grooves 51 are uniformly opened along the circumference of the outer wall of valve disc 5, and the grooves 51 are axially connected along valve disc 5 to allow the medium to pass through; after the grooves 51 are opened in the circumference, the axial section of valve disc 5 is a gear-shaped structure.

[0041] like Figure 4 As shown, a conical groove 52 is provided at the center of the upper surface of the valve disc 5, which is used to align with the spring seat 6; a stepped groove 53 is provided at the center of the lower surface of the valve disc 5; the stepped groove 53 and the stepped protrusion 43 cooperate to align the valve disc 5 with the sealing ring 4. The diameter of the side wall 54 of the stepped groove 53 is larger than the outer wall diameter of the stepped protrusion 43; this allows the medium to flow out through the gap between the outer wall of the stepped protrusion 43 and the side wall 54 of the stepped groove 53.

[0042] Spring seat 6 is a hollow cylindrical structure, such as Figure 5 As shown, the bottom of the spring seat 6 is provided with a ball head 61; the ball head 61 cooperates with the conical groove 52 to achieve alignment; the top of the spring seat 6 is provided with a drainage channel 62; the side wall of the drainage channel 62 is uniformly provided with balance holes 63 along the circumference.

[0043] The working process of a differential pressure balancing valve is as follows:

[0044] The medium is a mixture of hydrogen and water vapor. The external medium enters pipe 42 through the medium channel of upstream flange 1 and contacts the lower surface of valve disc 5. When the thrust generated by the medium on the lower surface of valve disc 5 overcomes the weight of valve disc 5, the weight of spring seat 6, the weight of spring 7, and the friction between the outer wall of valve disc 5 and the inner wall of valve body 3, the medium pushes valve disc 5 and spring seat 6 upwards, compressing spring 7; valve disc 5 separates from sealing ring 4; the medium flows out through the gap between the outer wall of stepped protrusion 43 and the side wall 54 of stepped groove 53, and the side wall 54 of stepped groove 53 generates a reaction force on the flowing medium, achieving rapid release of the medium. It then enters the inner cavity of valve body 3 through groove 51; subsequently, the medium enters the discharge channel 62 through balance hole 63, achieving communication with the medium channel of downstream flange 2, realizing pressure relief, and balancing the pressure difference between upstream flange 1 and downstream flange 2.

[0045] As the medium is continuously released into the medium channel of the downstream flange 2, when the combined force of the pressure inside the valve body 3 and the force of the spring 7 is greater than the medium thrust, the spring seat 6 is pushed to drive the valve disc 5 back down until the valve disc 5 is pressed back onto the valve body groove 41 of the sealing ring 4.

[0046] When the pressure difference between upstream flange 1 and downstream flange 2 is greater than or equal to 0.65 MPa, the differential pressure balancing valve starts to relieve pressure.

[0047] In this invention, the valve body 3 and the sealing ring 4 are connected by threads. The compression of the spring 7 is adjusted according to the threaded connection between the valve body 3, the adjusting screw 8, and the locking nut 9. A planar metal sealing structure is adopted between the valve disc 5 and the stepped protrusion 43 on the sealing ring 4 to ensure good sealing under small pressure differences, while meeting the erosion and wear resistance requirements of the differential pressure balancing valve. When the pressure of the hydrogen + water vapor medium reaches the set pressure point, the lift force generated by the medium on the lower surface of the valve disc 5 overcomes the force of the spring 7, the weight of the valve disc 5, the spring seat 6, the spring 7, and the friction between the valve body 3. The moving part begins to move upward, the valve disc 5 and the spring seat 6 are lifted, the valve disc 5 separates from the sealing ring 4, and the reaction force generated by the gap between the outer wall of the stepped protrusion 43 and the side wall 54 of the stepped groove 53 when the medium flows through plays a role in promoting the rapid discharge of the medium. The medium is discharged into the inner cavity of the valve body 3, realizing pressure relief and balancing the pressure difference at both ends of the pipeline. As the medium is continuously released into the downstream pipeline, when the combined force of the pressure inside the valve body 3 and the force of the spring 7 is greater than the lifting force of the medium, the spring seat 6 is pushed to drive the valve disc 5 to start to return to its seat, and finally the valve disc 5 is pressed against the sealing surface of the sealing ring 4.

[0048] This invention integrates a guide structure and valve disc 5 into one unit, reducing the possibility of misalignment during force transmission. Through the design of this differential pressure balancing valve structure, the invention achieves the following effects: the designed sealing ring structure and O-ring sealing type ensure good sealing performance of the differential pressure balancing valve; under inlet pressure ≤90%Ps, the valve sealing performance meets the requirements of GB / T12243-2021 and API 527; overpressure ≤10%Ps, reseating pressure ≤10%Ps, and discharge capacity meets design requirements.

[0049] The key technologies of this differential pressure balancing valve structure are threefold:

[0050] 1. Sealing Ring Structure: The upstream and downstream flanges are secured to the sealing ring with bolts and nuts for flange sealing. The sealing ring has grooves on both sides, housing an O-ring for sealing, ensuring excellent flange sealing performance. The valve seat and sealing ring are integrated into a single design; during normal pipeline operation, the valve seat and valve disc close tightly, guaranteeing a good seal.

[0051] 2. Planar metal sealing structure: Considering the possibility of impurities in the medium, this differential pressure balancing valve adopts a planar metal sealing structure. The sealing surface is wider at the top and narrower at the bottom, resulting in good sealing performance.

[0052] 3. Guiding Structure: The design integrates the guiding structure and valve disc into one unit, avoiding issues related to connection method, fit clearance, and guiding length that can occur with separate designs. Six grooves are formed on the side surface of the valve disc for media discharge. The ungrooved portion of the valve disc, which contacts the valve body, serves as the guiding surface. This design maximizes the contact area between the guiding surface and the valve body while meeting discharge requirements, and also improves the surface roughness and fit length of the mating surfaces. Simultaneously, the spring seat directly transmits the spring force to the valve disc's force-bearing surface, reducing the possibility of misalignment during force transmission, ensuring uniform force distribution on the valve disc, and improving the stability of the differential pressure balancing valve. This makes it suitable for frequent opening conditions.

[0053] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A differential pressure balancing valve, characterized in that: The valve includes an upstream flange (1), a downstream flange (2), a valve body (3), a sealing ring (4), a valve disc (5), a spring seat (6), a spring (7), an adjusting screw (8), and two O-rings (10). The upstream flange (1) is vertically axially positioned. The downstream flange (2) is located above the upstream flange (1) and coaxially connected to it. Medium channels are provided along the axes of both the upstream flange (1) and the downstream flange (2). The sealing ring (4) is located at the connection point between the upstream flange (1) and the downstream flange (2), and its position is aligned with that of the upstream flange (1). Corresponding to the medium channel of the downstream flange (2); the valve body (3) is a hollow cylindrical structure; the valve body (3) is axially and vertically installed on the upper surface of the sealing ring (4); the valve disc (5), spring seat (6), spring (7) and adjusting screw (8) are all set in the inner cavity of the valve body (3); the valve disc (5) is set on the top of the sealing ring (4); the spring seat (6) is set on the top of the valve disc (5); the spring (7) is axially and vertically set on the top of the spring seat (6); the adjusting screw (8) is set on the top of the spring (7), and the outer wall of the adjusting screw (8) is threaded to the inner wall of the valve body (3); One O-ring (10) is located at the joint between the lower surface of the sealing ring (4) and the upstream flange (1); the other O-ring (10) is located at the joint between the upper surface of the sealing ring (4) and the downstream flange (2). The sealing ring (4) is a column structure; a columnar valve body groove (41) is opened at the center of the upper surface of the sealing ring (4) for placing the valve body (3) and the valve disc (5) in the inner cavity of the valve body (3); a pipe (42) is coaxially opened at the bottom of the valve body groove (41); the pipe (42) is connected to the medium channel of the upstream flange (1); A stepped protrusion (43) is provided at the connection between the top of the pipe (42) and the valve body groove (41); the side wall of the stepped protrusion (43) is an inclined wall; the pipe (42) and the valve disc (5) are aligned coaxially through the stepped protrusion (43); the upper and lower surfaces of the sealing ring (4) are provided with ring grooves (44), and each ring groove (44) is embedded with an O-ring (10) to achieve sealing with the upstream flange (1) and the downstream flange (2); The valve disc (5) is a column structure; the outer wall of the valve disc (5) is in contact with the inner wall of the valve body (3); grooves (51) are uniformly opened along the circumference of the outer wall of the valve disc (5), and the grooves (51) are axially connected along the valve disc (5) to realize the passage of the medium; after the grooves (51) are opened in the circumference, the axial section of the valve disc (5) is a gear-shaped structure. A conical groove (52) is provided at the center of the upper surface of the valve disc (5), and the valve disc (52) is aligned with the spring seat (6); a stepped groove (53) is provided at the center of the lower surface of the valve disc (5); the valve disc (5) is aligned with the sealing ring (4) by the cooperation of the stepped groove (53) and the stepped protrusion (43). The diameter of the sidewall (54) of the stepped groove (53) is larger than the diameter of the outer wall of the stepped protrusion (43); thus enabling the medium to flow out through the gap between the outer wall of the stepped protrusion (43) and the sidewall (54) of the stepped groove (53); The spring seat (6) is a hollow cylindrical structure; a ball head (61) is provided at the bottom of the spring seat (6); the ball head (61) cooperates with the conical groove (52) to achieve alignment; a drainage channel (62) is provided at the top of the spring seat (6); a balance hole (63) is uniformly provided along the circumference of the side wall of the drainage channel (62).

2. A differential pressure balancing valve according to claim 1, characterized in that: It also includes a locking nut (9) and two O-rings (10); wherein the locking nut (9) is fitted on the outer wall of the adjusting screw (8) and located on the top of the valve body (3); after the relative position of the adjusting screw (8) and the valve body (3) is adjusted to the correct position, it is locked by the locking nut (9).

3. A differential pressure balancing valve according to claim 1, characterized in that: The working process of a differential pressure balancing valve is as follows: External medium enters the pipeline (42) through the medium channel of the upstream flange (1) and contacts the lower surface of the valve disc (5). When the thrust generated by the medium on the lower surface of the valve disc (5) overcomes the gravity of the valve disc (5), the gravity of the spring seat (6), the gravity of the spring (7), and the friction between the outer wall of the valve disc (5) and the inner wall of the valve body (3), the medium pushes the valve disc (5) and the spring seat (6) upward and compresses the spring (7). The valve disc (5) separates from the sealing ring (4). The medium flows out through the gap between the outer wall of the stepped protrusion (43) and the side wall (54) of the stepped groove (53), and enters the inner cavity of the valve body (3) through the groove (51). Subsequently, the medium enters the discharge channel (62) through the balance hole (63) to achieve communication with the medium channel of the downstream flange (2), thereby achieving pressure relief and balancing the pressure difference between the upstream flange (1) and the downstream flange (2). During the process of the medium continuously being released into the medium channel of the downstream flange (2), when the combined force of the pressure inside the valve body (3) and the force of the spring (7) is greater than the medium thrust, the spring seat (6) is pushed to drive the valve disc (5) to fall back until the valve disc (5) is pressed back onto the valve body groove (41) of the sealing ring (4).

4. A differential pressure balancing valve according to claim 3, characterized in that: The medium is a mixture of hydrogen and water vapor; the medium is rapidly released by the reaction force generated by the side wall (54) of the stepped groove (53) on the flowing medium; when the pressure difference between the upstream flange (1) and the downstream flange (2) is greater than or equal to 0.65 MPa, the differential pressure balancing valve starts to release pressure.

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