A negative pressure prevention device for loading and unloading operations

Abstract

This utility model discloses a negative pressure prevention device for loading and unloading operations, relating to the field of sulfuric acid pipeline transportation. It includes a pressure-reducing pipe and a first pipeline. A pressure-reducing box is installed at the top of the pressure-reducing pipe, and a connecting box is connected to the top of the pressure-reducing box. A vent pipe is fixed to the end of the connecting box, and a connecting pipe is connected to one side of the pressure-reducing box. A rim is provided on the outer wall of the seal. When the electric valve is closed, the negative pressure inside the first pipeline attracts the seal, causing it to wrap around the top of the pressure-reducing pipe. The negative pressure also draws the rim on the seal inward, creating a gap between the seal and the pressure-reducing box. External gas enters the pressure-reducing box through the vent pipe and flows into the first pipeline through the connecting pipe, thereby filling the negative pressure area inside the first pipeline near the connecting pipe end, reducing the negative pressure and thus protecting the electric valve.

Description

Technical Field

[0001] This utility model relates to the field of sulfuric acid pipeline transportation, specifically a device for preventing negative pressure during loading and unloading operations. Background Technology

[0002] In sulfuric acid transfer operations at the dock, sulfuric acid is usually transferred through dedicated pipelines. One end of these pipelines is connected to storage tanks or transport containers for storing sulfuric acid, and the other end is connected to the dock's loading and unloading equipment. With the help of the power generated by the pumps, sulfuric acid is transported from one place to another along the pipelines, completing the liquid transfer during the loading and unloading process.

[0003] The ends of sulfuric acid transport pipelines are equipped with corresponding valves to control the transport and shut-off of sulfuric acid. Commonly used electrically driven valves are mainly electric gate valves. Electric gate valves use a motor to drive the gate to lift and lower to open and close the pipeline. The two sides of the electric gate valve are connected to the transport pipeline and the drainage pipeline, respectively.

[0004] When the electric gate valve is closed, a negative pressure state is easily formed at the connection between the drain pipe and the valve. This is because at the moment the valve is closed, the flow of sulfuric acid in the transmission pipe suddenly stops, while the volume change of the residual sulfuric acid in the drain pipe causes the pressure at the connection to drop sharply. This negative pressure will exert a continuous suction force on the valve's sealing structure, destroying the tight fit between the sealing surfaces. Long-term high-intensity negative pressure will cause the seals to wear, deform, or even fail, seriously affecting the service life of the electric gate valve. Summary of the Invention

[0005] Therefore, the purpose of this utility model is to provide a negative pressure prevention device for loading and unloading operations, so as to solve the technical problems mentioned in the background.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a negative pressure prevention device for loading and unloading operations, comprising a pressure reducing pipe and a first pipe, a pressure reducing box being provided at the top of the pressure reducing pipe, a connecting box being connected to the top of the pressure reducing box, a vent pipe being fixed to the end of the connecting box, a connecting pipe being connected to one side of the pressure reducing box, a protruding pipe being provided at the bottom of the inside of the pressure reducing box, a pressure reducing assembly being installed inside the pressure reducing box, the pressure reducing assembly including a sealer, a rim being provided on the outer wall of the sealer, and a sealing block being fixed to the bottom of the sealer.

[0007] By adopting the above technical solution, the technical problem that the negative pressure near the valve when the valve is closed can easily damage the valve structure is solved. When the electric valve is closed, the negative pressure inside the first pipe attracts the seal, causing the seal to wrap around the top of the pressure reducing pipe. The negative pressure also pulls the edge ring on the seal inward, creating a gap between the seal and the pressure reducing box. External gas enters the pressure reducing box through the vent pipe and flows into the first pipe through the connecting pipe, thereby filling the negative pressure area inside the first pipe near the connecting pipe end, reducing the negative pressure. By reducing the negative pressure intensity, the electric valve is protected.

[0008] The present invention is further configured such that a protrusion is fixed on the top of the pressure relief box, and a groove is provided inside the connecting box, and a sealing gasket is installed inside the groove.

[0009] Preferably, the pressure reducing box and the connecting box are connected by a flange, and the sealing gasket can seal the connection between the two.

[0010] The present invention is further configured such that the outer wall diameter of the rim is equal to the inner wall diameter of the pressure relief box, and the inner wall diameter of the rim is greater than the outer wall diameter of the convex tube.

[0011] Preferably, when sulfuric acid flows from the pressure reducing pipe into the connecting pipe, the edge ring blocks the top of the pressure reducing box. When negative pressure occurs in the pressure reducing pipe, the edge ring absorbs and shrinks onto the seal, creating a gap between the edge ring and the pressure reducing box.

[0012] The present invention is further configured such that multiple sets of suction holes are provided inside the convex tube, and the bottom wall of the edge ring is lower than the bottom wall of the sealing block.

[0013] Preferably, the negative pressure inside the pressure-reducing tube causes the rim to be absorbed and contracted through the suction hole.

[0014] The present invention is further provided that a filter is installed at the top of the vent pipe, and the filter is a polypropylene fiber filter.

[0015] Preferably, the air filter filters the gas flowing into the ventilation pipe to prevent dust from the outside air from entering the sulfuric acid pipeline.

[0016] The present invention is further configured such that the sealer is a conical body and is made of fluororubber.

[0017] As a preferred option, fluororubber has good corrosion resistance, deformation properties, and the ability to withstand high negative pressure.

[0018] The present invention is further configured such that one end of the first pipe is connected to a connecting pipe, an electric gate valve is installed on the top of the connecting pipe, and a second pipe is connected to one side of the connecting pipe.

[0019] Preferably, the electric gate valve controls the flow of sulfuric acid between the first and second pipes via a gate valve located inside the connecting pipe.

[0020] The present invention is further configured such that two sets of connecting pipes are provided on the outer wall of one end of the first pipe, and a gate valve is installed on the top of the connecting pipe.

[0021] Preferably, when personnel need to replace the seal, they can manually close the gate valve to prevent sulfuric acid inside the first pipeline from flowing into the pressure reducing pipe and the connecting pipe.

[0022] In summary, the present invention has the following main advantages:

[0023] This invention solves the technical problem that negative pressure near the valve when it is closed can easily damage the valve structure by setting up a pressure-reducing pipe, a pressure-reducing box, a vent pipe, a seal, a side ring, and a connecting pipe. When the electric valve is closed, the negative pressure inside the first pipe attracts the seal, causing the seal to wrap around the top of the pressure-reducing pipe. The negative pressure also draws the side ring on the seal inward, creating a gap between the seal and the pressure-reducing box. External gas enters the pressure-reducing box through the vent pipe and flows into the first pipe through the connecting pipe, thereby filling the negative pressure area inside the first pipe near the connecting pipe end, reducing the negative pressure, and thus protecting the electric valve by reducing the negative pressure intensity.

[0024] This utility model incorporates a vent pipe, a connecting box, a protrusion, a groove, a sealing gasket, and a gate valve. The connecting box and the pressure reducing box are connected by a flange. When the seal cracks or breaks, personnel can manually close the gate valve connected to the bottom of the pressure reducing pipe and the connecting pipe, preventing sulfuric acid from flowing into the pressure reducing pipe and the connecting pipe from the first pipeline. Personnel can then remove the vent pipe 2 and the connecting box from the top of the pressure reducing box and replace the seal inside the pressure reducing box. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall device of this utility model;

[0026] Figure 2 This is a schematic diagram of the pressure-reducing component of this utility model;

[0027] Figure 3 This is a schematic diagram of the pressure relief box of this utility model;

[0028] Figure 4This is a schematic diagram of the connection box of this utility model;

[0029] Figure 5 This is a schematic diagram of the pressure-reducing pipe seal of this utility model;

[0030] Figure 6 This is a structural diagram of the seal of this utility model;

[0031] Figure 7 This is a schematic diagram of the sealing of the pressure relief box of this utility model;

[0032] Figure 8 This is a schematic diagram of the interior of the vent pipe of this utility model.

[0033] Explanation of reference numerals in the attached figures:

[0034] 1. Pressure reducing pipe; 101. Pressure reducing box; 102. Protruding pipe; 103. Protrusion; 104. Connecting pipe; 105. Suction hole; 2. Vent pipe; 201. Connecting box; 202. Groove; 203. Sealing gasket; 204. Cavity; 205. Blocking ball; 206. Support ring; 207. Through hole; 3. Sealer; 301. Side ring; 302. Sealing block; 4. Filter; 5. First pipe; 501. Connecting pipe; 502. Gate valve; 503. Second pipe; 6. Connecting pipe; 601. Electric gate valve. Detailed Implementation

[0035] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0036] The embodiments of this utility model will be described below based on its overall structure.

[0037] Please see Figure 1 — Figure 7The system includes a pressure-reducing pipe 1 and a first pipe 5. A pressure-reducing box 101 is mounted on the top of the pressure-reducing pipe 1. A connecting box 201 is connected to the top of the pressure-reducing box 101. A vent pipe 2 is fixed to the end of the connecting box 201. A connecting pipe 104 is connected to one side of the pressure-reducing box 101. A protruding pipe 102 is mounted on the bottom of the inside of the pressure-reducing box 101. A pressure-reducing assembly is installed inside the pressure-reducing box 101. The pressure-reducing assembly includes a sealer 3. A rim ring 301 is mounted on the outer wall of the sealer 3. A sealing block 302 is fixed to the bottom of the sealer 3. This design solves the problem that negative pressure near the valve when the valve is closed can easily damage the valve structure. In the technical case, when the electric valve 601 is closed, the negative pressure inside the first pipe 5 attracts the seal 3, causing the seal 3 to wrap around the top of the pressure reducing pipe 1. The negative pressure also draws the edge ring 301 on the seal 3 inward, creating a gap between the seal 3 and the pressure reducing box 10. External gas enters the pressure reducing box 10 through the vent pipe 2 and flows into the first pipe 5 through the connecting pipe 104, thereby filling the negative pressure area inside the first pipe 5 near the end of the connecting pipe 6, reducing the negative pressure. This reduces the intensity of the negative pressure, thus protecting the valve of the electric valve 601.

[0038] For details regarding the above embodiments, please refer to [link / reference]. Figure 3 and Figure 4 The top of the pressure relief box 101 is fixed with a protrusion 103, and the inside of the connecting box 201 is provided with a groove 202, and a sealing gasket 203 is installed inside the groove 202. The pressure relief box 101 and the connecting box 201 are connected by a flange connection, and the sealing gasket 203 can seal the connection between the two.

[0039] For details regarding the above embodiments, please refer to [link / reference]. Figure 6 and Figure 7 The outer diameter of the rim 301 is equal to the inner diameter of the pressure reducing box 101. The inner diameter of the rim 301 is greater than the outer diameter of the convex tube 102. When sulfuric acid flows from the pressure reducing tube 1 into the connecting tube 104, the rim 301 blocks the top of the pressure reducing box 101. When a negative pressure occurs in the pressure reducing tube 1, the rim 301 absorbs and shrinks onto the sealer 3, creating a gap between the rim 301 and the pressure reducing box 101.

[0040] For details regarding the above embodiments, please refer to [link / reference]. Figure 6 The inside of the convex tube 102 has multiple sets of suction holes 105. The bottom wall of the edge ring 301 is lower than the bottom wall of the sealing block 302. The negative pressure inside the pressure reducing tube 1 adsorbs and shrinks the edge ring 301 through the suction holes 105.

[0041] For details regarding the above embodiments, please refer to [link / reference]. Figure 2A filter 4 is installed at the top of the ventilation pipe 2. The filter 4 is a polypropylene fiber filter, which is an air filter. The filter 4 filters the gas flowing into the ventilation pipe 2 to prevent dust in the outside air from entering the sulfuric acid pipeline.

[0042] For details regarding the above embodiments, please refer to [link / reference]. Figure 5 , Figure 6 and Figure 7 The seal 3 is set as a cone shape and is made of fluororubber. Fluororubber has good corrosion resistance, deformation properties and the ability to withstand high negative pressure.

[0043] For details regarding the above embodiments, please refer to [link / reference]. Figure 1 One end of the first pipe 5 is connected to a connecting pipe 6. An electric gate valve 601 is installed at the top of the connecting pipe 6. A second pipe 503 is connected to one side of the connecting pipe 6. The electric gate valve 601 controls the flow of sulfuric acid between the first pipe 5 and the second pipe 503 through a gate valve installed inside the connecting pipe 6.

[0044] For details regarding the above embodiments, please refer to [link / reference]. Figure 1 Two sets of connecting pipes 501 are provided on the outer wall of one end of the first pipe 5. A gate valve 502 is installed on the top of the connecting pipe 501. When personnel need to replace the sealer 3, they can manually close the gate valve 502 so that the sulfuric acid inside the first pipe 5 no longer flows into the pressure reducing pipe 1 and the connecting pipe 104.

[0045] Please see Figure 8 The vent pipe 2 has a cavity 204 inside, and a blocking ball 205 is installed inside the cavity 204. When the seal 3 is damaged or cracked, sulfuric acid will slowly flow into the vent pipe 2, and the blocking ball 205 will float on the sulfuric acid until the blocking ball 205 blocks and seals the top port of the cavity 204, thereby preventing sulfuric acid from flowing out through the vent pipe 2. The bottom inner wall of the cavity 204 is fixed with a support ring 206, and the support ring 206 has multiple sets of through holes 207 inside. When the outside gas flows into the vent pipe 2, the support ring 206 supports the blocking ball 205, and the gas inside the vent pipe 2 flows into the pressure reducing box 101 through the through holes 207.

[0046] In practical operation, during sulfuric acid transfer at a dock, sulfuric acid flows from the second pipe 503 to the first pipe 5. The first pipe 5 and the second pipe 503 are connected by a connecting pipe 6. When sulfuric acid flows into the first pipe 5, a portion of the sulfuric acid inside the first pipe 5 flows into the pressure reducing pipe 1 through a set of connecting pipes 501 on the outer wall of the first pipe 5. The sulfuric acid flowing inside the pressure reducing pipe 1 pushes the rubber seal 3 in the pressure reducing box 101 fixed at the top of the pressure reducing pipe 1 upwards. The edge ring on the outer wall of the seal 3... 301 seals the top of the pressure reducing box 101 and the inside of the connecting box 201, and the sulfuric acid pushes the edge ring 301 upward, causing the edge ring 301 to expand outward, so that the edge ring 301 can fit tightly against the inner wall of the pressure reducing box 101, thereby preventing the sulfuric acid from flowing into the vent pipe 2. The sulfuric acid flowing into the pressure reducing box 101 flows into the connecting pipe 104 through the gap between the sealer 3 and the protruding tube 102 inside the pressure reducing box 101. The flow in the flow pipe 104 then flows into the first pipe 5 through the connecting pipe 501 connected to its end.

[0047] When the electric gate valve 601 seals and blocks the inside of the connecting pipe 6, due to the high flow rate of sulfuric acid, the sulfuric acid, due to its inertia, causes a local negative pressure at the end of the first pipe 5 on one side of the connecting pipe 6. The low pressure inside the first pipe 5 absorbs the seal 3, causing the seal 3 to descend to the bottom of the pressure reducing box 101. Since the bottom wall of the edge ring 301 is lower than the bottom wall of the sealing block 302 at the bottom of the seal 3, the edge ring 301 wraps around the outer wall of the convex tube 102. The negative pressure inside the pressure reducing pipe 1 is absorbed by the edge ring 301 through the suction hole 10 on the inner wall of the convex tube 102, causing the edge ring 301 to contract towards the seal 3. A gap appears between the seal 3 and the inner wall of the pressure reducing box 101. There is negative pressure inside both the connecting pipe 104 and the bottom of the first pipe 5 of the pressure reducing pipe 1. Therefore, the negative pressure inside the connecting pipe 104 is absorbed by the gas inside the vent pipe 2. The absorbed gas flows into the first pipe 5, thereby reducing the degree of negative pressure inside the first pipe 5. And the outside gas flows into the vent pipe 2 through the filtration of the filter 4.

[0048] Although embodiments of the present invention have been shown and described, these specific embodiments are merely explanations of the present invention and are not intended to limit the invention. The specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. After reading this specification, those skilled in the art may make modifications, substitutions, and variations to the embodiments as needed without departing from the principles and spirit of the present invention, provided that such modifications, substitutions, and variations are within the scope of the claims of the present invention and are protected by patent law.

Claims

1. A negative pressure prevention device for loading and unloading operations, comprising a pressure reducing pipe (1) and a first pipeline (5), characterized in that: The pressure-reducing tube (1) is provided with a pressure-reducing box (101) at the top, and a connecting box (201) is connected to the top of the pressure-reducing box (101). A vent pipe (2) is fixed to the end of the connecting box (201). A connecting pipe (104) is connected to one side of the pressure-reducing box (101). A protruding tube (102) is provided at the bottom of the inside of the pressure-reducing box (101). A pressure-reducing assembly is installed inside the pressure-reducing box (101). The pressure-reducing assembly includes a sealer (3). A rim ring (301) is provided on the outer wall of the sealer (3). A sealing block (302) is fixed at the bottom of the sealer (3).

2. The negative pressure prevention device for loading and unloading operations according to claim 1, characterized in that: The top of the pressure relief box (101) is fixed with a protrusion (103), and the inside of the connecting box (201) is provided with a groove (202), and a sealing gasket (203) is installed inside the groove (202).

3. The negative pressure prevention device for loading and unloading operations according to claim 1, characterized in that: The outer diameter of the rim (301) is equal to the inner diameter of the pressure relief box (101), and the inner diameter of the rim (301) is greater than the outer diameter of the convex tube (102).

4. A negative pressure prevention device for loading and unloading operations according to claim 1, characterized in that: The inside of the protruding tube (102) is provided with multiple sets of suction holes (105), and the bottom wall of the edge ring (301) is lower than the bottom wall of the sealing block (302).

5. A negative pressure prevention device for loading and unloading operations according to claim 1, characterized in that: A filter (4) is installed at the top of the vent pipe (2), and the filter (4) is a polypropylene fiber filter.

6. A negative pressure prevention device for loading and unloading operations according to claim 1, characterized in that: The seal (3) is set as a cone shape and is made of fluororubber.

7. A negative pressure prevention device for loading and unloading operations according to claim 1, characterized in that: One end of the first pipe (5) is connected to a connecting pipe (6), an electric gate valve (601) is installed on the top of the connecting pipe (6), and a second pipe (503) is connected to one side of the connecting pipe (6).

8. A negative pressure prevention device for loading and unloading operations according to claim 1, characterized in that: Two sets of connecting pipes (501) are provided on the outer wall of one end of the first pipe (5), and a gate valve (502) is installed on the top of the connecting pipe (501).

9. A negative pressure prevention device for loading and unloading operations according to claim 1, characterized in that: The vent pipe (2) has a cavity (204) inside, and a blocking ball (205) is provided inside the cavity (204). The blocking ball (205) is made of polypropylene and its diameter is larger than the diameter of the top and bottom inner walls of the cavity (204).

10. A negative pressure prevention device for loading and unloading operations according to claim 9, characterized in that: A support ring (206) is fixed to the inner wall of the bottom end of the cavity (204), and multiple sets of through holes (207) are opened inside the support ring (206).

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