An integrated dual-path vacuum tube

Abstract

The invention discloses an integrated double-path vacuum tube: comprising a heat-insulating outer tube, a return air tube, a liquid inlet tube, a converging pipe and a sealing cover; the outer tube is sleeved on the return air tube, the return air tube is sleeved on the liquid inlet tube, the converging pipe is arranged at the end of the heat-insulating outer tube, the converging pipe is independent of the liquid inlet tube at the end of the heat-insulating outer tube, and is sealed and connected with the return air tube, an insulation layer is arranged between the heat-insulating outer tube and the return air tube, the liquid inlet tube is eccentrically arranged in the return air tube, one end of the liquid inlet tube is fixedly connected to the inner wall of the return air tube, so that the central axis of the liquid inlet tube and the central axis of the return air tube are not colinear, the sealing cover is arranged at the two ends of the heat-insulating outer tube, and the sealing covers at the protruding two ends of the liquid inlet tube are arranged; the heat brought by the double pipes can also effectively solve the problem of vaporizing the low-temperature liquid, heating the tank body, and increasing the BOG gas, increasing the tank body pressure, and increasing the discharge, and the greater the loss.

Description

Technical Field

[0001] The invention relates to the technical field of vacuum pipeline transportation, in particular to an integral double-path vacuum tube. Background Art

[0002] The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

[0003] The pipelines in the LNG filling station process generally use vacuum pipes, which have a good cold preservation effect and can reduce the gasification of LNG into BOG during operation. They are very important process pipelines in the entire LNG filling process. However, at present, most manufacturers on the market use two independent pipes for inlet and return liquid. The disadvantages and shortcomings of two pipes are mainly manifested in the following aspects:

[0004] 1) The heat generated by two tubes is always greater than that of a single tube, which increases the generation of BOG, and the tank pressure rises quickly, which will cause excessive LNG discharge;

[0005] 2) Whether on the skid or in the on-site pipeline, narrow space always exists. The double-pipe arrangement often sacrifices some process requirements to meet the installation needs. This can be seen in most of the operational stations. This will cause air blockage or liquid sealing, which will have an adverse effect on the transportation of liquids;

[0006] 3) In terms of installation, the required installation materials, installation time and cost of two pipes are higher than those of a single pipe. In terms of the length of the entire pipeline, the longer the pipeline, the more waste there is.

[0007] 4) The cost of transporting two pipes independently will also increase. Depending on the transportation distance, the occupied transportation space will increase, and the cost will also increase significantly.

[0008] 5) In terms of maintenance, the cost of maintaining vacuum is also twice as much, and the cost of use and maintenance is significantly increased.

[0009] Based on the above problems, it is necessary to propose an integrated dual-path vacuum tube structure which is easier to install, operate and maintain and has comprehensive excellent performance. Summary of the invention

[0010] The purpose of the present invention is to provide an integrated dual-path vacuum tube in view of the above-mentioned problems, which solves the problems in the prior art that the gas and liquid pipelines are independently set up in the NG filling station process, which increases the installation and transportation space and the maintenance cost, and the heat generated by the two independent pipelines is always too large, which increases the generation of BOG, causes the tank body to increase pressure quickly, and causes excessive LNG discharge.

[0011] This solution is implemented as follows:

[0012] An integral dual-path vacuum tube comprises an insulating outer tube, an air return tube, a liquid inlet tube, a confluence tube and a sealing cover; the insulating outer tube is sleeved on the air return tube, the air return tube is sleeved on the liquid inlet tube, the confluence tube is arranged at the end of the insulating outer tube, the confluence tube is independent of the liquid inlet tube at the end of the insulating outer tube, and is sealed and connected with the air return tube.

[0013] Preferably, a heat-insulating layer is provided between the heat-insulating outer tube and the air return tube, and the liquid inlet tube is eccentrically arranged in the air return tube.

[0014] Preferably, one end of the liquid inlet pipe is fixedly connected to the inner wall of the return air pipe so that the central axis of the liquid inlet pipe is not colinear with the central axis of the return air pipe, and the sealing cover is arranged at the two ends of the insulation outer tube, and the sealing covers are arranged at the protruding ends of the liquid inlet pipe.

[0015] Preferably, the confluence pipe comprises an external joint, a connector and a baffle chamber; the connector and the external joint are respectively arranged at the upper and lower ends of the baffle chamber, the baffle chamber is an arc-shaped pipe, the external joint is arranged at one end of the baffle chamber, and the external joint is an arc-shaped structure;

[0016] Preferably, the connector includes an inner annular surface, an outer annular surface and a connecting port, the connecting port is connected to the end of the return air pipe, the inner annular surface is concave, and the concave radius of the inner annular surface matches the arc structure of the outer end wall of the liquid inlet pipe.

[0017] Preferably, the outer annular surface is arranged in an outward concave shape, the outer annular surface matches the arc-shaped structure of the inner wall of the return air pipe, and there is an arc transition between the inner annular surface and the outer annular surface.

[0018] Preferably, the confluence conduit as a whole adopts a streamlined structure and is integrally formed.

[0019] Preferably, the confluence pipe and the liquid inlet pipe are installed horizontally and on the same straight line during installation.

[0020] This solution provides a method for installing a dual-path vacuum tube, comprising the following steps:

[0021] 1. You need to confirm the size of the insulation outer pipe, and then select the corresponding pipe clamp according to the size to support the pipe;

[0022] 2. According to the size of the selected integral dual-channel vacuum tube, select the corresponding flanges or valves and other pipe fittings, weld the inlet and outlet confluence pipes and inlet and outlet liquid inlet pipes at the front and rear ends of the vacuum tube, connect other equipment or pipelines at the front or back, and then it can be used;

[0023] 3. During installation, except for the special circumstances where the pipe openings are arranged up and down, they are generally arranged left and right. That is, during installation, the confluence pipe and the liquid inlet pipe are installed horizontally and on the same straight line.

[0024] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0025] 1. When low-temperature liquid flows in the liquid phase pipe, it can better balance the temperature rise of the gas phase pipe, reduce the generation and emission of BOG, and directly save costs for customers.

[0026] 2. The eccentric wall structure effectively solves the technical problems of pipe threading and fixing.

[0027] 3. The unique design of the manifold is more conducive to the flow of gas and liquid and reduces the liquid seal phenomenon of the gas phase pipe.

[0028] 4. Compared with double pipes, the installation efficiency is higher, fewer supports and pipe clamps are used, and the cost is lower.

[0029] 5. The maintenance cost is also half of that of double-tube vacuum pumping. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0031] Figure 2 It is a structural schematic diagram of the confluence pipeline in the present invention.

[0032] Figure 3 It is a side view structural schematic diagram of the whole invention.

[0033] Figure 4 The present invention Figure 3 Schematic diagram of the cross-sectional structure of BB.

[0034] Markings in the figure: 1. Insulated outer pipe; 2. Return air pipe; 3. Liquid inlet pipe; 4. Converging pipe; 5. Sealing cover; 6. Insulation layer; 7. External joint; 8. Connector; 9. Deflection chamber; 10. Inner annular surface; 11. Outer annular surface; 12. Connection port. DETAILED DESCRIPTION

[0035] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0036] Any feature disclosed in this specification (including any additional claims and abstract), unless otherwise stated, may be replaced by other alternative features that are equivalent or have similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0037] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by the terms "up", "down", "left", "right", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0038] In addition, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features.

[0039] Example 1

[0040] like Figures 1 to 4 As shown, an integral dual-path vacuum tube comprises an insulation outer tube 1, an air return tube 2, a liquid inlet tube 3, a converging pipe 4 and a sealing cover 5; the insulation outer tube is sleeved on the air return tube 2, the air return tube 2 is sleeved on the liquid inlet tube 3, an insulation layer 6 is arranged between the insulation outer tube 1 and the air return tube 2, the liquid inlet tube 3 is eccentrically arranged in the air return tube 2, that is, one end of the liquid inlet tube 3 is fixedly connected to the inner wall of the air return tube 2, so that the central axis of the liquid inlet tube 3 is not colinear with the central axis of the air return tube 2, the sealing cover 5 is arranged at both ends of the insulation outer tube 1, the sealing covers 5 protruding from both ends of the liquid inlet tube 3 are arranged, the converging pipe 4 is arranged at both ends of the insulation outer tube 1, and the converging pipe 4 is connected through the air return tube 2;

[0041] Based on the above structure, since the liquid inlet pipe 3 passes through the sealing cover 5 on the left and right, and the liquid inlet pipe 3 is eccentrically arranged in the return pipe 2, the end of the return pipe 2 is not coplanar with the liquid inlet pipe 3, and the pipe space is connected to the converging pipe 4, so that the return pipe 2 and the liquid inlet pipe 3 are only opposed to each other at the end of the insulation outer pipe 1 to form two separate ends, the liquid is transmitted through the liquid inlet pipe 3, and the gas passes out through the return pipe 2 and is connected to the next component through the converging pipe 4;

[0042] The return air pipe 2 is within the length of the insulation outer pipe 1, and the liquid inlet pipe 3 is always in the return air pipe 2. When low-temperature liquid flows in the liquid inlet pipe 3, since the entire liquid inlet pipe 3 is arranged in the return air pipe 2, heat transfer is performed on the return air pipe 2, which can better balance the temperature rise in the return air pipe 2, effectively reduce the generation of BOG and its emission, and directly save costs for customers.

[0043] Furthermore, since the liquid inlet pipe 3 is arranged in the air return pipe 2, the installation area and maintenance difficulty of the pipeline are greatly reduced.

[0044] In the prior art, cryogenic liquids transported through pipelines require two vacuum tubes, one for inlet and one for return. This application innovatively uses one vacuum tube to solve this problem. This application effectively solves the problem of two pipelines occupying a large space, and saves the supporting materials and construction volume of one pipeline, greatly improving the efficiency of pipeline installation at the work site. At the same time, using one pipeline for inlet and return air can also effectively solve the problem of heat from the double pipelines causing the cryogenic liquid to vaporize, the tank body to heat up, and the increase in BOG gas, the increase in tank body pressure, and the increase in emissions, resulting in greater losses. After multiple field practical data feedback, it was found that when the liquid in the liquid phase tube is flowing, it can effectively balance the temperature of the gas phase tube, liquefy part of the gas, and rapidly reduce the tank body pressure.

[0045] The confluence pipe 4 includes an external joint 7, a connector 8 and a baffle chamber 9; the connector 8 and the external joint 7 are respectively arranged at the upper and lower ends of the baffle chamber 9, the baffle chamber 9 is an arc-shaped pipe, the external joint 7 is arranged at one end of the baffle chamber 9, and the external joint 7 is an arc phase structure, and is connected to an external pipe or valve through a regular external joint 7 to control the confluence pipe 4 and the airflow passage in which it is located;

[0046] The connector 8 includes an inner annular surface 10, an outer annular surface 11 and a connecting port 12. The connecting port 12 is connected to the end of the return air pipe 2. The inner annular surface 10 is concave. The concave radius of the inner annular surface 10 matches the arc structure of the outer end wall of the liquid inlet pipe 3, so that the confluence pipe 4 can fit more closely with the liquid inlet pipe 3, so that the gas in the confluence pipe 4 can pass through to a greater extent.

[0047] The outer annular surface 11 is arranged in an outward concave shape, and the outer annular surface 11 matches the arc structure of the inner wall of the return air pipe 2. The inner annular surface 10 and the outer annular surface 11 have an arc transition to form a connecting port 12, so that the connecting port 12 forms an irregular opening; the outer annular surface 11 matches the arc structure of the inner wall of the return air pipe 2, so that the outer annular surface 11 can fit more closely with the wall of the return air pipe 2, simplifying the difficulty of installation and also increasing the amount of gas passing through.

[0048] The confluence pipe 4 adopts a streamlined structure as a whole and is formed in one piece, which is more conducive to the flow of gas and liquid.

[0049] Installation method of this vacuum tube: 1. You need to confirm the size of the insulation outer tube, and then select the corresponding pipe clamp according to the size to support the pipeline.

[0050] 2. According to the size of the selected integral dual-way vacuum tube, select the corresponding flanges or valves and other pipe fittings, weld the inlet and outlet confluence pipes 4 and the inlet and outlet liquid inlet pipes 3 at the front and rear ends of the vacuum tube, connect other equipment or pipelines at the front or back, and it can be received and used.

[0051] 3. During installation, except for the special case where the pipe openings are arranged up and down, they are generally arranged left and right. That is, during installation, the confluence pipe 4 and the liquid inlet pipe 3 are installed horizontally and on the same straight line.

[0052] If the confluence pipe 4 and the liquid inlet pipe 3 are arranged up and down during installation, on the one hand, a liquid seal of the gas phase pipe may be formed at the confluence pipe 4, and on the other hand, when the liquid flow rate in the liquid inlet pipe 3 is insufficient, the liquid may reduce the contact area of ​​the return air pipe 2, resulting in low heat exchange efficiency.

[0053] When installed horizontally, the above two issues can be taken into consideration at the same time. It can effectively prevent the liquid sealing phenomenon of the gas phase pipe, and increase the contact area between the liquid in the liquid inlet pipe 3 and the return gas pipe 2, ensuring the heat transfer efficiency, and better balancing the temperature rise in the return gas pipe 2. It can effectively reduce the generation and emission of BOG, directly saving costs for customers.

[0054] When maintaining the pipeline, you only need to check the vacuum degree, or perform vacuuming regularly as required by the instructions to ensure the thermal insulation effect of the pipeline.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An integrated dual-path vacuum tube, characterized in that: It includes an insulation outer tube, an air return tube, a liquid inlet tube, a converging tube and a sealing cover; the insulation outer tube is sleeved on the air return tube, the air return tube is sleeved on the liquid inlet tube, the converging tube is arranged at the end of the insulation outer tube, the converging tube is independent of the liquid inlet tube at the end of the insulation outer tube, and is sealed and connected with the air return tube; A heat-insulating layer is provided between the heat-insulating outer tube and the air return tube, and the liquid inlet tube is eccentrically arranged in the air return tube; One end of the liquid inlet pipe is fixedly connected to the inner wall of the air return pipe, so that the central axis of the liquid inlet pipe is not colinear with the central axis of the air return pipe, and the sealing covers are arranged at the two ends of the insulation outer pipe, and the sealing covers are arranged at the protruding ends of the liquid inlet pipe; The confluence pipe comprises an external joint, a connector and a baffle chamber; the connector and the external joint are respectively arranged at the upper and lower ends of the baffle chamber, the baffle chamber is an arc-shaped pipe, the external joint is arranged at one end of the baffle chamber, and the external joint is an arc-shaped structure; During installation, the confluence pipe and the liquid inlet pipe are installed horizontally and on the same straight line.

2. An integrated dual-path vacuum tube as claimed in claim 1, characterized in that: The connector includes an inner annular surface, an outer annular surface and a connecting port, the connecting port is connected to the end of the return air pipe, the inner annular surface is concave, and the concave radius of the inner annular surface matches the arc structure of the outer end wall of the liquid inlet pipe.

3. An integrated dual-path vacuum tube as claimed in claim 2, characterized in that: The outer annular surface is concavely arranged, the outer annular surface matches the arc-shaped structure of the inner wall of the return air pipe, and there is an arc transition between the inner annular surface and the outer annular surface.

4. An integrated dual-path vacuum tube as claimed in claim 1, characterized in that: The confluence pipe adopts a streamlined structure as a whole and is formed in one piece.

5. The method for installing the integrated dual-path vacuum tube according to claims 1 to 4 above is characterized in that: The following steps are involved: Step 1. Confirm the size of the insulation outer pipe, and then select the corresponding pipe clamp according to the size to support the pipe; Step 2. According to the size of the selected integral dual-channel vacuum tube, select the corresponding other pipe fittings, weld the inlet and outlet confluence pipes and the inlet and outlet liquid inlet pipes at the front and rear ends of the vacuum tube, connect other equipment or pipelines at the front or back, and then it can be used; other pipe fittings include: flanges or valves; Step 3. During installation, the pipe installation outlets are arranged up and down or left and right.

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