Mass flowmeter

Abstract

The utility model provides a mass flow meter which comprises a housing and a flow meter body arranged in the housing, and two groups of pipelines which are connected with the flow meter body and used for liquid inlet and outlet are fixed on the housing through a thermal bridge structure; the heat bridge structure seals the space between the outer wall of the pipeline and the housing, and the heat bridge structure extends in a reciprocating mode in the axial direction of the pipeline so as to prolong a heat transfer path between the pipeline and the housing; according to the mass flow meter, the thermal bridge structure is connected between the outer wall of the pipeline and the housing in a sealed mode, and the pipeline in the housing and the flow meter body can be isolated from the external environment; besides, the heat bridge structure extends in a reciprocating mode in the axial direction of the pipeline, a heat transfer path between the housing and the pipeline can be increased, the phenomenon that low-temperature liquid in the pipeline is gasified due to heat transferred by the housing can be reduced, and the measuring precision of the flowmeter is improved; and meanwhile, the frosting of the housing can be reduced.

Description

Technical Field

[0001] This utility model relates to the field of flow measurement equipment, and more specifically, to a mass flow meter. Background Technology

[0002] For flow measurement of cryogenic liquids such as liquid hydrogen, in conventional Coriolis flow meters, the flow meter housing is directly connected to the inlet and outlet liquid components. The cryogenic liquid inside the inlet and outlet liquid components will directly transfer the cold energy to the housing, resulting in severe frost formation on the housing. At the same time, due to the large heat exchange area between the housing and the outside environment, the heat loss is serious, which will cause the liquid hydrogen in the leaching liquid component and the measuring pipeline to undergo a relatively serious vaporization phenomenon, affecting the measurement accuracy of the flow meter. Utility Model Content

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a mass flow meter that can be used for the accurate measurement of the flow rate of cryogenic liquid media, including but not limited to liquid hydrogen, liquid nitrogen, liquid ammonia, and liquid oxygen.

[0004] The embodiments of this utility model are achieved through the following technical solutions:

[0005] A mass flow meter includes a housing and a flow meter body disposed inside the housing. Two sets of pipes connected to the flow meter body for use as inlet and outlet pipes are fixed to the housing via a thermal bridge structure.

[0006] The thermal bridge structure seals the space between the outer wall of the pipe and the casing, and the thermal bridge structure extends axially along the pipe to extend the heat transfer path between the pipe and the casing.

[0007] Furthermore, the thermal bridge structure is located inside the housing.

[0008] Furthermore, the thermal bridge structure includes several layers of tubular components sleeved on the pipe; along the axial direction of the pipe, the interlayer between any two adjacent layers of tubular components is closed at one end, and the closed ends of any two adjacent layers of the interlayer are in opposite positions.

[0009] Furthermore, the interlayer located between the pipe and the innermost tubular component of the thermal bridge structure is sealed by a joint, which also serves as part of the thermal bridge structure and can simultaneously fix the outer end of the pipe.

[0010] The connector is located outside the housing and is connected to the pipeline to transport the medium.

[0011] Furthermore, the thermal bridge structure includes a first tubular member sleeved on the outer periphery of the pipe and a second tubular member sleeved on the outer periphery of the first tubular member;

[0012] One end of the second tubular member is closedly connected to the cover, and the other end located inside the cover is closedly connected to the first tubular member; the other end of the first tubular member extends to the outside of the cover and is closedly connected to the joint.

[0013] Furthermore, the connector is coaxially provided with a first connecting part and a second connecting part in the shape of a convex ring, and the second connecting part is located on the outer periphery of the first connecting part;

[0014] The first connecting part is connected to the pipe, and the second connecting part is connected to the innermost tubular component of the thermal bridge structure.

[0015] Furthermore, the pipe is arranged in a curved and tortuous manner within the casing to compensate for stress deformation of the pipe.

[0016] Furthermore, the pipe is arranged in a "Z" shape.

[0017] Furthermore, the flow meter body includes a dual-channel measuring tube and a flow divider. The dual-channel measuring tube is bent into a triangular structure inside the housing, and the two ends of the dual-channel measuring tube are mounted on the flow divider in a converged state.

[0018] Furthermore, the distributor has two sets of three-way flow paths, wherein the first set of pipes is connected to one end of the dual-channel measuring tube through the first set of three-way flow paths, and the second set of pipes is connected to the other end of the dual-channel measuring tube through the second set of three-way flow paths.

[0019] The technical solution of this utility model embodiment has at least the following advantages and beneficial effects:

[0020] In this mass flow meter, the pipes for the inlet and outlet of the flow meter body are fixed to the casing through a thermal bridge structure. The thermal bridge structure is sealed between the outer wall of the pipe and the casing, which can isolate the pipe and the flow meter body inside the casing from the external environment. In addition, the thermal bridge structure extends back and forth along the axial direction of the pipe, which increases the heat transfer path between the casing and the pipe, which can reduce or avoid the vaporization of low-temperature liquid inside the pipe and improve the measurement accuracy of the flow meter. At the same time, it can also reduce frost formation on the casing. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the internal structure of the mass flow meter according to an embodiment of the present invention. Figure 1 ;

[0022] Figure 2 This is a schematic diagram of the internal structure of the mass flow meter according to an embodiment of the present invention. Figure 2 ;

[0023] Figure 3 for Figure 2 An enlarged view of part A in the image;

[0024] Icons: 1-Cover, 2-Flowmeter body, 20-Diverter, 200-T-way flow path, 21-Dual-channel measuring tube, 3-Pipe, 4-Thermal bridge structure, 40-Tube, 400-First tube, 401-Second tube, 41-Interlayer, 42-Sealing structure, 5-Connector, 50-First connection, 51-Second connection. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Reference Figures 1 to 3 A mass flow meter includes a housing 1 and a flow meter body 2 disposed inside the housing 1. The flow meter body 2 is connected to the external environment of the housing 1 through two sets of pipes 3, wherein one set of pipes 3 is used for the inlet of the flow meter body 2 and the other set of pipes 3 is used for the outlet of the flow meter body 2.

[0027] To address the issues of frost formation on the casing 1 and heat transfer between the casing 1 and the pipe 3 leading to easy vaporization of the liquid inside the pipe 3, this invention adds a thermal bridge 4 between the casing 1 and the pipe 3 to reduce heat transfer between them. Specifically, both sets of pipes 3 are fixed to the casing 1 via the thermal bridge structure 4, unlike the traditional flowmeter where the pipes are directly welded to the casing.

[0028] Reference Figure 1 and Figure 3 In fact, the thermal bridge structure 4 is sealed between the outer wall of the pipe 3 and the casing 1, so that the inside of the casing 1 is isolated from the external environment.

[0029] Among them, the thermal bridge structure 4 extends back and forth along the axial direction of the pipe 3 to extend the heat transfer path between the pipe 3 and the casing 1. Therefore, the thermal bridge structure 4 can adopt a structure similar to the water surface ripples. The thermal bridge structure 4 spreads outward from the pipe 3 as the ripple center and connects to the casing 1 on the periphery.

[0030] Reference Figure 3In this embodiment, in order to further extend the heat transfer path of the thermal bridge structure 4, the thermal bridge structure 4 includes several layers of tubular members 40 sleeved on the pipe 3. In the axial or length extension direction of the pipe 3, the interlayer 41 between any two adjacent layers of tubular members 40 is closed at one end, and the closed ends of any two adjacent layers of interlayer 41 are in opposite positions. Therefore, during the heat transfer process, the heat needs to be continuously transferred through the pipe walls of the aforementioned tubular members 40.

[0031] It is easy to understand that the tubular component 40 can be a pipe with a circular tube shape, a triangular, quadrilateral, pentagonal or other irregular shape cross-section. In this embodiment, several tubular components 40 are circular tube structures.

[0032] The thermal bridge structure 4 can be entirely located outside the casing 1, or the thermal bridge structure 4 can be partially located outside the casing 1 and partially located inside the casing 1. In this embodiment, the thermal bridge structure 4 is located inside the casing 1, which can reduce the thermal contact between the heat transfer structure 4 and the external environment, and further reduce the heat transfer to the pipe 3.

[0033] Reference Figure 2 and Figure 3 In this embodiment, the thermal bridge structure 4 has two sets of tubular members 40, namely, the thermal bridge structure 4 includes a first tubular member 400 sleeved on the outer periphery of the pipe 3, and a second tubular member 401 sleeved on the outer periphery of the first tubular member 400.

[0034] Reference Figure 3 In this configuration, one outer end of the second tubular member 401 is closedly connected to the cover 1, and the other end of the second tubular member 401 located inside the cover 1 is closedly connected to the first tubular member 400. The closure method is a sealing structure 42 disposed between the outer wall of the end of the first tubular member 400 and the inner wall of the end of the second tubular member 401. One outer end of the first tubular member 400 extends to the outer side of the cover 1 and is closedly connected to the connector 5.

[0035] Reference Figure 3 The connector 5 is located on the outside of the housing 1. The function of the connector 5 is to connect with the pipe 3 to transport liquid media. The connector 5 is coaxially provided with a first connecting part 50 and a second connecting part 51 in the shape of a convex ring. The second connecting part 51 is located on the outer periphery of the first connecting part 50. The protruding length of the first connecting part 50 is greater than the protruding length of the second connecting part 51. The first connecting part 50 is connected to the pipe 3, and the second connecting part 51 is connected to the innermost tubular member 40 in the thermal bridge structure 4. That is, in this embodiment, the second connecting part 51 is connected to one outer end of the first tubular member 400.

[0036] Therefore, in this embodiment, the joint 5 can be used as part of the thermal bridge structure 4 for heat transfer, and the joint 5 can also fix the outer end of the pipe 3. By increasing the heat transfer path through the thermal bridge 4, the heat transfer between the pipe 3 and the casing 1 is limited, and the casing 1 will not frost due to low temperature.

[0037] Reference Figure 1 and Figure 2 The flow meter body 2 includes a dual-channel measuring tube 21 and a flow divider 20. The dual-channel measuring tube 21 includes two sets of parallel pipe flow paths. Inside the housing 1, the dual-channel measuring tube 21 is bent into a triangular structure, and the two ends of the dual-channel measuring tube 21 are mounted on the flow divider 20 in a converged state.

[0038] The distributor 20 has two sets of three-way flow paths 200. The first set of pipes 3 is connected to one end of the dual-channel measuring tube 21 through the first set of three-way flow paths 200, and the second set of pipes 3 is connected to the other end of the dual-channel measuring tube 21 through the second set of three-way flow paths 200. That is, after the liquid medium enters the distributor 20 along one set of pipes 3, it is diverted to the dual-channel measuring tube 21. The liquid medium flowing out of the dual-channel measuring tube 21 is collected by the distributor 20 and discharged through the other set of pipes 3.

[0039] The dual-channel measuring tube 21 is equipped with corresponding detection components. When the liquid medium flows in the dual-channel measuring tube 21, a Coriolis force proportional to the mass flow rate is generated. This force causes the dual-channel measuring tube 21 to undergo torsional vibration. The detection coils installed at both ends of the dual-channel measuring tube 21 generate signals with different phases. The phase difference between these two signals is proportional to the mass flow rate of the fluid flowing through the sensor. By measuring these phase differences, the mass flow rate of the fluid can be calculated. The structural principle is existing technology and will not be described in detail here.

[0040] In addition, when the liquid medium flows through the internal parts of the casing 1, such as the joint 5, the pipe 3, and the distributor 20, the components will shrink because they are in direct contact with the liquid medium. At the same time, the temperature of the casing 1 is relatively high and the shrinkage amount is inconsistent with that of the internal components, which will block the shrinkage. Therefore, the pipe 3 is more likely to shrink and deform along the direction of stress.

[0041] Therefore, in order to solve the problem of excessive shrinkage stress and deformation of pipe 3 under ultra-low temperature conditions, pipe 3 is arranged in a curved and tortuous manner inside the casing 1 to compensate for the stress deformation of pipe 3.

[0042] Reference Figure 1 and Figure 2In this embodiment, the pipe 3 is arranged in a "Z" shape, so that the material of the pipe 3 meets the shrinkage stress requirements of the pipe 3 at low temperature, eliminating the influence of excessive stress on the performance of the flow meter. At this time, the stress is mainly concentrated at the bend of the "Z" shaped pipe 3, so the pipe 3 has the ability to compensate for deformation, so as not to affect the measurement accuracy or damage the equipment.

[0043] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. For those skilled in the art, the present utility model can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A mass flow meter, comprising a housing (1) and a flow meter body (2) disposed inside the housing (1), wherein two sets of pipes (3) connected to the flow meter body (2) for serving as inlet and outlet liquids are fixed to the housing (1) via a thermal bridge structure (4), characterized in that: The thermal bridge structure (4) seals the space between the outer wall of the pipe (3) and the casing (1), and the thermal bridge structure (4) extends back and forth along the axial direction of the pipe (3) to extend the heat transfer path between the pipe (3) and the casing (1).

2. The mass flow meter according to claim 1, characterized in that, The thermal bridge structure (4) is located inside the housing (1).

3. The mass flow meter according to claim 2, characterized in that, The thermal bridge structure (4) includes several layers of tubular components (40) sleeved on the pipe (3); in the axial direction of the pipe (3), the interlayer (41) between any two adjacent layers of tubular components (40) is closed at one end, and the closed ends of any two adjacent layers of interlayer (41) are in opposite positions.

4. The mass flow meter according to claim 3, characterized in that, The interlayer (41) located between the pipe (3) and the innermost tubular member (40) in the thermal bridge structure (4) is sealed by a joint (5); The connector (5) is located outside the housing (1) and is connected to the pipe (3) to transport the medium.

5. The mass flow meter according to claim 4, characterized in that, The thermal bridge structure (4) includes a first tubular member (400) sleeved on the outer periphery of the pipe (3) and a second tubular member (401) sleeved on the outer periphery of the first tubular member (400); One end of the second tubular member (401) is closedly connected to the cover (1), and the other end located inside the cover (1) is closedly connected to the first tubular member (400); the other end of the first tubular member (400) extends to the outside of the cover (1) and is closedly connected to the connector (5).

6. The mass flow meter according to claim 4 or 5, characterized in that, The connector (5) is coaxially provided with a first connecting part (50) and a second connecting part (51) in the shape of a convex ring, and the second connecting part (51) is located on the outer periphery of the first connecting part (50); The first connecting part (50) is connected to the pipe (3), and the second connecting part (51) is connected to the innermost tubular component (40) in the thermal bridge structure (4).

7. The mass flow meter according to any one of claims 1 to 5, characterized in that, The pipe (3) is arranged in a curved and meandering manner inside the casing (1) to compensate for the stress deformation of the pipe (3).

8. The mass flow meter according to claim 7, characterized in that, The pipe (3) is arranged in a "Z" shape.

9. The mass flow meter according to any one of claims 1 to 5, characterized in that, The flow meter body (2) includes a dual-channel measuring tube (21) and a flow divider (20). The dual-channel measuring tube (21) is bent into a triangular structure inside the housing (1), and the two ends of the dual-channel measuring tube (21) are mounted on the flow divider (20) in a converged state.

10. The mass flow meter according to claim 9, characterized in that, The distributor (20) has two sets of three-way flow paths (200); The first group of pipes (3) is connected to one end of the dual-channel measuring tube (21) through the first group of three-way flow path (200), and the second group of pipes (3) is connected to the other end of the dual-channel measuring tube (21) through the second group of three-way flow path (200).

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