A low-temperature liquid flow performance testing system and its testing method

Abstract

The present invention relates to the technical field of flow meter calibration, and provides a cryogenic liquid flow performance test system and a test method thereof. Among them, the cryogenic liquid flow performance test system includes a weighing device, which includes a container, a first pipeline, a second pipeline, a weighing scale and a lifting mechanism. One end of the first pipeline is communicated with the container, and the other end of the first pipeline is connected with an automatic docking joint; one end of the second pipeline is communicated with the first pipeline through the automatic docking joint; the weighing scale is arranged below the container; the lifting mechanism is used to drive the container to approach or move away from the weighing scale in the vertical direction. By adding an automatic docking joint and a lifting mechanism in the weighing device, the present invention can realize the rapid connection or disconnection of the first pipeline and the second pipeline. During the weighing and metering stage, the container is independently supported on the weighing scale, which can further improve the accuracy of weighing and metering, and provide more accurate data support for the subsequent calibration of the flow meter to be measured.

Description

Technical Field

[0001] The present invention relates to the technical field of flowmeter calibration, and in particular, to a cryogenic liquid flow performance test system and a test method thereof. Background Art

[0002] A Coriolis mass flowmeter is a flow measurement device that measures the mass flow rate in a pipeline based on the modulation effect of the fluid mass flow rate on the oscillation of a vibrating tube (i.e., the Coriolis force phenomenon). The Coriolis mass flowmeter can directly measure the mass flow rate and has good measurement accuracy.

[0003] Many existing flowmeters similar to Coriolis mass flowmeters often need to be calibrated after production to determine whether the measurement accuracy meets the requirements. Among them, the standard meter method or the weighing method is often used to calibrate the accuracy of the flowmeter to be tested. When using the weighing method, a weighing device is often required to weigh the container and the medium in the container for subsequent calculation of the mass of the medium flowing into the container per unit time.

[0004] For example, the patent document with the publication number CN109387265A discloses a cryogenic mass flowmeter performance test device and method, which can realize the calibration of flowmeters using the standard meter method and the weighing method. However, when the above test device calibrates the flowmeter using the weighing method, the liquid storage bottle is always placed on the electronic balance. When the cryogenic medium flows into the liquid storage bottle, it will impact the inner wall of the liquid storage bottle and cause the liquid storage bottle to shake, affecting the accuracy of the weighing measurement result. At the same time, since the liquid storage bottle is always connected to the commutator through a pipeline, during actual weighing measurement, the pipeline connected to the liquid storage bottle will also affect the actual weighing measurement result, thereby causing a certain measurement error. Summary of the Invention

[0005] The first object of the present invention is to provide a cryogenic liquid flow performance test system to solve the technical problem of certain weighing measurement errors existing in the prior art when calibrating flowmeters using the weighing method.

[0006] The second object of the present invention is to provide a cryogenic liquid flow performance test method to solve the technical problem of certain calibration errors existing in the prior art when calibrating flowmeters using the weighing method.

[0007] The embodiments of the present invention are implemented through the following technical solutions:

[0008] On the one hand, the present invention provides a cryogenic liquid flow performance test system, including a weighing device, and the weighing device includes:

[0009] A container;

[0010] A first pipeline, one end of the first pipeline is communicated with the container, and the other end of the first pipeline extends in the vertical direction and is connected with an automatic docking joint;

[0011] A second pipeline, one end of the second pipeline is communicated with the first pipeline through the automatic docking joint;

[0012] A weighing device, arranged below the container; and,

[0013] A jacking mechanism, the jacking mechanism is used to drive the container to approach or move away from the weighing device in the vertical direction;

[0014] Wherein, when the container is carried on the weighing device, the jacking mechanism is completely separated from the container, and the automatic docking joint is disconnected; when the container moves away from the weighing device, the first pipeline and the second pipeline are connected and conducted through the automatic docking joint.

[0015] Optionally, the automatic docking joint includes:

[0016] An upper joint, internally provided with an upper diversion cavity and an upper outlet; the upper diversion cavity penetrates through the upper joint, the upper outlet is communicated with the upper diversion cavity, and the inner diameter of the upper outlet is smaller than the inner diameter of the upper diversion cavity; and,

[0017] An upper sealing head, sealingly arranged in the upper outlet;

[0018] An upper elastic body, the upper sealing head is connected to the inner wall of the upper diversion cavity through the upper elastic body, and the upper elastic body is used to drive the upper sealing head to move along the axis of the upper diversion cavity; and,

[0019] A lower joint, internally provided with a lower diversion cavity; the lower diversion cavity penetrates through the lower joint; and,

[0020] A movable sleeve, located between the upper joint and the lower joint; the movable sleeve is slidably connected to the lower joint, the movable sleeve internally is provided with a middle diversion cavity and a lower inlet, the middle diversion cavity penetrates through the movable sleeve and is communicated with the lower diversion cavity, and the lower inlet is communicated with the middle diversion cavity; and,

[0021] A lower sealing head, sealingly arranged in the lower inlet; the lower sealing head is adapted to the upper sealing head, and the lower sealing head is connected to the inner wall of the lower diversion cavity; and,

[0022] A lower elastic body, the movable sleeve and the lower joint are connected through the lower elastic body, so as to drive the lower joint to move along the axis of the middle diversion cavity through the lower elastic body;

[0023] Among them, the first pipeline is communicated with the lower joint, and the second pipeline is communicated with the upper joint.

[0024] Further, one end of the upper joint is provided with an annular sealing groove communicated with the upper outlet. One end of the movable sleeve away from the lower joint is provided with an annular sealing portion adapted to the annular sealing groove. The annular sealing portion is sealingly arranged in the annular sealing groove. The inner diameter of the annular sealing portion is not less than the inner diameter of the upper outlet, and an annular sealing ring is arranged between the outer wall of the annular sealing portion and the inner wall of the annular sealing groove.

[0025] Further, one end of the movable sleeve away from the lower inlet extends into the lower diversion cavity and is slidably connected with the lower joint;

[0026] The outer wall of the movable sleeve is provided with an annular abutting portion. The abutting portion is aligned with the bottom of the upper joint, and the outer diameter of the abutting portion is not less than the outer diameter of the bottom of the upper joint;

[0027] The lower elastic body includes a lower return spring. The lower return spring is sleeved on the outer wall of the lower joint. One end of the lower return spring is connected with the lower joint, and the other end of the lower return spring is connected with the abutting portion.

[0028] Further, an upper sealing ring is arranged between the outer wall of the upper sealing head and the inner wall of the upper outlet, and a lower sealing ring is arranged between the outer wall of the lower sealing head and the inner wall of the lower inlet.

[0029] Further, a fixed cylinder, an upper guide post and an upper fixing bracket are arranged inside the upper diversion cavity. A reset cavity is arranged inside the fixed cylinder. The axis of the reset cavity coincides with the axis of the upper diversion cavity. The fixed cylinder is provided with a through hole communicated with the reset cavity, and the through hole is adapted to the upper guide post;

[0030] One end of the upper guide post is connected with the upper sealing head, and the other end of the upper guide post extends axially into the reset cavity along the upper diversion cavity;

[0031] The upper fixing bracket is provided with a notch, and the fixed cylinder is connected with the inner wall of the upper diversion cavity through the upper fixing bracket;

[0032] The upper elastic body includes an upper return spring. The upper return spring is sleeved on the outer wall of the upper guide post. One end of the upper return spring is connected with the upper guide post, and the other end of the upper return spring is connected with the inner wall of the reset cavity.

[0033] Further, a lower guiding post and a lower fixing bracket are arranged inside the lower diversion cavity. One end of the lower guiding post is connected to the lower sealing head, and the other end of the lower guiding post is connected to the lower fixing bracket. The lower fixing bracket is provided with a notch and is connected to the inner wall of the lower diversion cavity.

[0034] Optionally, the jacking mechanism includes:

[0035] a bracket for supporting the container; and,

[0036] a lifting device for driving the bracket to approach or move away from the weighing device in the vertical direction;

[0037] Wherein, a supporting part is arranged on the container, and the supporting part extends downward after passing through the bracket in the vertical direction.

[0038] Further, a concave part is arranged on the bracket and recesses downward, and the container is arranged inside the concave part;

[0039] A bearing plate is arranged at the bottom of the container, and the area of the bearing plate is larger than the area of the bottom of the container. The bearing plate bears on the concave part, and the supporting part is arranged on the bearing plate and passes through the concave part.

[0040] On the other hand, the present invention provides a method for testing the flow performance of cryogenic liquids. The flowmeter under test is calibrated by using the cryogenic liquid flow performance test system described above. The method is characterized by including the following steps:

[0041] Before weighing and metering, the jacking mechanism drives the container to move away from the weighing device in the vertical direction, so that the first pipeline and the second pipeline are connected and conducted through the automatic docking joint;

[0042] Subsequently, a medium is introduced into the container through the first pipeline and the second pipeline; after a certain period of time, the jacking mechanism drives the container to approach the weighing device in the vertical direction; at this time, the automatic docking joint between the first pipeline and the second pipeline is disconnected and separated;

[0043] After the container bears on the weighing device and the jacking mechanism is completely separated from the container, the weighing and metering can be started by using the weighing device.

[0044] The technical solution of the embodiment of the present invention has at least the following advantages and beneficial effects:

[0045] By adding an automatic docking joint and a lifting mechanism to the weighing device, the present invention can achieve the rapid connection or disconnection of the first pipeline and the second pipeline, and effectively prevent the medium from flowing out of the pipeline after the two pipelines are disconnected; at the same time, during the weighing and metering stage, the container is independently carried on the weighing scale, so that only the container and the medium inside it are weighed and metered during the weighing stage. Therefore, compared with the existing weighing devices, the weighing accuracy can be further improved, providing more accurate data support for the subsequent verification of the flow meter to be measured. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0047] Figure 1 Schematic diagram of the structure of the cryogenic liquid flow performance test system provided in Embodiment 1 of the present invention;

[0048] Figure 2 Schematic diagram of the structure of the weighing device provided in Embodiment 1 of the present invention;

[0049] Figure 3 Schematic diagram of the structure of the automatic docking joint provided in Embodiment 1 of the present invention;

[0050] Figure 4 Schematic diagram of the structure of the upper joint provided in Embodiment 1 of the present invention;

[0051] Figure 5 Schematic diagram of the structure of the upper joint in the sealed state provided in Embodiment 1 of the present invention;

[0052] Figure 6 Schematic diagram of the structure of the lower joint provided in Embodiment 1 of the present invention;

[0053] Figure 7 Schematic diagram of the structure of the lower joint in the sealed state provided in Embodiment 1 of the present invention;

[0054] Figure 8 Schematic diagram of the structure of the automatic docking joint when it is disconnected and separated provided in Embodiment 1 of the present invention;

[0055] Figure 9 Schematic diagram of the structure of the automatic docking joint when it is connected and conducting provided in Embodiment 1 of the present invention;

[0056] Figure 10 Schematic diagram of the structure of the bracket provided in Embodiment 1 of the present invention;

[0057] Figure 11 This is a schematic structural diagram of the container provided in Embodiment 1 of the present invention.

[0058] Icons: 1 - weighing device, 2 - commutator, 3 - flow meter under test, 4 - standard flow meter, 5 - gas-liquid separator, 6 - submersible pump, 7 - storage tank, 8 - automatic docking joint, 11 - container, 12 - weighing scale, 13 - chassis, 14 - bracket, 1401 - concave part, 15 - support feet, 16 - first pipeline, 17 - second pipeline, 18 - bearing plate, 19 - support part, 120 - drive motor, 121 - screw jack, 122 - transmission gearbox, 123 - transmission shaft, 124 - third pipeline, 125 - fourth pipeline, 81 - upper joint, 8101 - upper diversion cavity, 8102 - upper inlet, 8103 - upper outlet, 8104 - annular sealing groove, 82 - movable sleeve, 8201 - middle diversion cavity, 8202 - lower inlet, 8203 - annular sealing part, 8204 - abutting part, 83 - lower joint, 8301 - lower diversion cavity, 8302 - lower outlet, 84 - upper sealing head, 85 - upper return spring, 86 - fixed cylinder, 8601 - return cavity, 8602 - through hole, 87 - upper guide post, 88 - upper fixed bracket, 89 - upper sealing ring, 810 - annular sealing ring, 811 - lower sealing head, 812 - lower guide post, 813 - lower fixed bracket, 814 - lower sealing ring, 815 - lower return spring. Detailed implementation manners

[0059] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0060] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0061] It should be noted that: similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0062] In the description of the present invention, it should be noted that if terms such as "upper", "lower", "vertical", "horizontal", "inner", "outer", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of this application is usually placed during use. This is 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 orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention.

[0063] In the description of the present invention, it should also be noted that unless otherwise clearly specified and limited, if terms such as "set", "installed", "connected", "linked" are used, they should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0064] Embodiment 1

[0065] This embodiment provides a cryogenic liquid flow performance test system for calibrating the flow meter 3 to be measured. Please refer to Figure 1 , this cryogenic liquid flow performance test system includes a storage tank 7, a submersible pump 6, a gas-liquid separator 5, a standard flow meter 4, a flow meter 3 to be measured, a commutator 2, and a weighing device 1.

[0066] Among them, the weighing device 1 includes a container 11 and a weighing scale 12. The storage tank 7, the submersible pump 6, the gas-liquid separator 5, the standard flow meter 4, the flow meter 3 to be measured, and the commutator 2 are sequentially connected through pipelines. The commutator 2 includes at least one inlet end and at least two outlet ends. The inlet end of the commutator 2 is connected to the flow meter 3 to be measured through a pipeline. One of the outlet ends of the commutator 2 is connected to the storage tank 7 through a pipeline, and the other outlet end of the commutator 2 is connected to the container 11 of the weighing device 1 through a pipeline.

[0067] Considering that in the existing test system, the container 11 of the weighing device 1 is always placed on the weighing scale 12, and the container 11 is always connected to the commutator 2 through a pipeline, there is a certain measurement error in the weighing and metering stage, which affects the final calibration result. Therefore, in this embodiment, the weighing device 1 is improved to solve the technical problem of measurement error in the weighing and metering stage of the weighing device 1.

[0068] Please refer to Figure 2, the weighing device 1 of this embodiment includes a chassis 13, a container 11, a weighing device 12, and a lifting mechanism. Among them, the weighing device 12 can be, but is not limited to, an electronic balance. The weighing device 12 is located below the container 11. The lifting mechanism is arranged on the chassis 13, and the weighing device 12 is arranged below the chassis 13. At the same time, support feet 15 for supporting the chassis 13 and the lifting mechanism are arranged at the bottom of the chassis 13. The support feet 15 can be arranged in four and are sequentially distributed at the four corners around the chassis 13, so as to provide better support for the chassis 13.

[0069] At the same time, continue to refer to Figure 2 , a first pipeline 16 is arranged on the container 11. One end of the first pipeline 16 is communicated with the container 11, and the other end of the first pipeline 16 extends in the vertical direction and is connected with an automatic docking joint 8. It also includes a second pipeline 17 for connecting the commutator 2 and the container 11. The second pipeline 17 is connected to the first pipeline 16 through the automatic docking joint 8.

[0070] The lifting mechanism is used to drive the container 11 to approach or move away from the weighing device 12 in the vertical direction. Among them, when the container 11 is carried on the weighing device 12, the lifting mechanism is completely separated from the container 11, and the automatic docking joint 8 is disconnected so that the first pipeline 16 and the second pipeline 17 are disconnected; when the container 11 moves away from the weighing device 12, the first pipeline 16 and the second pipeline 17 can be connected and conducted through the automatic docking joint 8, so that the medium can smoothly enter the container 11.

[0071] Through the above settings, before weighing and metering, the lifting mechanism drives the container 11 away from the weighing device 12, and at this time the first pipeline 16 and the second pipeline 17 are connected and conducted through the automatic docking joint 8, and the medium can smoothly enter the container 11 through the first pipeline 16 and the second pipeline 17; when a certain amount of medium flows into the container 11 and is stable, then use the lifting mechanism to drive the container 11 close to the weighing device 12 until the container 11 is carried on the weighing device 12 and the lifting mechanism is completely separated from the container 11, and the automatic docking joint 8 between the first pipeline 16 and the second pipeline 17 is also disconnected. At this time, only the container 11 is carried on the weighing device 12, so as to realize weighing only the container 11 and the medium inside it during the weighing and metering stage, so as to improve the accuracy during weighing and metering.

[0072] Specifically, please refer to Figure 3 , the automatic docking joint 8 includes an upper joint 81, a movable sleeve 82, and a lower joint 83. Among them, the first pipeline 16 is communicated with the lower joint 83, the second pipeline 17 is communicated with the upper joint 81, and the second pipeline 17 and the upper joint 81 are kept in a fixed state during the whole weighing and metering stage.

[0073] Please refer to Figure 4, an upper joint 81 is internally provided with an upper diversion cavity 8101 which penetrates the upper joint 81 along the axis of the upper joint 81. At the same time, an upper inlet 8102 and an upper outlet 8103 which are communicated with the upper diversion cavity 8101 are also arranged inside the upper joint 81. The inner diameter of the upper outlet 8103 is smaller than that of the upper diversion cavity 8101. The second pipeline 17 is communicated with the inside of the upper diversion cavity 8101 through the upper inlet 8102.

[0074] Secondly, continue to refer to Figure 4 , one end of the upper joint 81 close to the upper outlet 8103 is provided with an annular sealing groove 8104 communicated with the upper outlet 8103, and the inner diameter of the annular sealing groove 8104 is larger than that of the upper outlet 8103.

[0075] Please refer to Figure 5 , the inside of the upper joint 81 is also provided with an upper sealing head 84, an upper elastic body, a fixing cylinder 86, an upper guiding column 87 and an upper fixing bracket 88.

[0076] Among them, the upper sealing head 84 is sealingly arranged in the upper outlet 8103. At this time, the outer wall of the upper sealing head 84 is attached to the inner wall of the upper outlet 8103 to block the upper outlet 8103 through the upper sealing head 84 and prevent the medium from flowing out from the upper outlet 8103. At the same time, an annular upper sealing ring 89 is also arranged between the outer wall of the upper sealing head 84 and the inner wall of the upper outlet 8103 to further improve the sealing performance when the upper sealing head 84 blocks the upper outlet 8103.

[0077] Exemplarily, the upper sealing ring 89 is made of an elastic material. The upper sealing ring 89 can be fixedly arranged on the outer wall of the upper sealing head 84 or on the inner wall of the upper outlet 8103. The setting position of the upper sealing ring 89 is not specially limited here. At the same time, one upper sealing ring 89 can be arranged, or two can be arranged in parallel. When two upper sealing rings 89 are arranged, the sealing performance can be further improved.

[0078] Continue to refer to Figure 5 , the upper fixing bracket 88 is fixedly arranged inside the upper diversion cavity 8101, and the upper fixing bracket 88 is provided with a notch for the medium to pass through. The fixing cylinder 86 is fixedly arranged on the upper fixing bracket 88, so that the fixing cylinder 86 is connected to the inner wall of the upper diversion cavity 8101 through the upper fixing bracket 88 to fix the fixing cylinder 86 inside the upper diversion cavity 8101.

[0079] Meanwhile, a reset cavity 8601 is provided inside the fixed cylinder 86. The axis of the reset cavity 8601 coincides with the axis of the upper diversion cavity 8101, and a through hole 8602 communicating with the reset cavity 8601 is provided on the fixed cylinder 86. The through hole 8602 is adapted to the upper guide post 87. At this time, one end of the upper guide post 87 is fixedly connected to the upper sealing head 84, and the other end of the upper guide post 87 extends axially along the upper diversion cavity 8101 into the reset cavity 8601 of the fixed cylinder 86 and can pass through the through hole 8602 provided on the fixed cylinder 86. By providing the through hole 8602 on the fixed cylinder 86 for the upper guide post 87 to pass through, the movement stroke of the upper guide post 87 can be increased on the basis of minimizing the length of the fixed cylinder 86 as much as possible.

[0080] Continue to refer to Figure 5 , the upper elastic body is used to drive the upper sealing head 84 to move along the axis of the upper diversion cavity 8101. The upper elastic body includes an upper reset spring 85. The upper reset spring 85 is sleeved on the outer wall of the upper guide post 87 and is located inside the reset cavity 8601. One end of the upper reset spring 85 is fixedly connected to the upper guide post 87, and the other end of the upper reset spring 85 is fixedly connected to the inner wall of the reset cavity 8601 of the fixed cylinder 86.

[0081] In the initial state, the upper reset spring 85 is in an extended state. At this time, the upper reset spring 85 applies an elastic force to the upper guide post 87 to push the upper sealing head 84 into the upper outlet 8103 through the upper guide post 87 to seal the upper outlet 8103. When a force in the axial direction of the upper diversion cavity 8101 is applied to the end of the upper sealing head 84 away from the upper guide post 87 and this force is greater than the elastic force of the upper reset spring 85, the upper sealing head 84 moves upward along the axis of the upper diversion cavity 8101. At this time, the upper sealing head 84 drives the upper guide post 87 to move upward along the axis of the upper diversion cavity 8101 so that the upper reset spring 85 is compressed to store an elastic force; conversely, when the force applied to the end of the upper sealing head 84 away from the upper guide post 87 is removed, the upper sealing head 84 can be reset under the action of the upper reset spring 85 and seal the upper outlet 8103 again.

[0082] Please refer to Figure 6 , a lower diversion cavity 8301 is provided inside the lower joint 83. The lower diversion cavity 8301 penetrates the lower joint 83 along the axis of the lower joint 83. The movable sleeve 82 is provided between the upper joint 81 and the lower joint 83. The movable sleeve 82 is slidably connected to the lower joint 83 so that the movable sleeve 82 can slide relative to the lower joint 83.

[0083] Continue to refer to Figure 6, the inside of the movable sleeve 82 is provided with a middle diversion cavity 8201 and a lower inlet 8202. The middle diversion cavity 8201 runs through the movable sleeve 82 along the axis of the movable sleeve 82 and communicates with the lower diversion cavity 8301. The lower inlet 8202 is arranged at one end of the movable sleeve 82 away from the lower joint 83 and communicates with the middle diversion cavity 8201. At this time, one end of the lower diversion cavity 8301 away from the movable sleeve 82 serves as a lower outlet 8302 for the medium to flow out, and the first pipeline 16 communicates with the lower diversion cavity 8301 through the lower outlet 8302.

[0084] It can be understood that during actual implementation, one end of the movable sleeve 82 away from the lower inlet 8202 can extend into the lower diversion cavity 8301 and be slidably connected to the lower joint 83, or one end of the lower joint 83 close to the lower inlet 8202 can extend into the middle diversion cavity 8201 and be slidably connected to the movable sleeve 82. No special limitation is made on the specific implementation method here.

[0085] Continue to refer to Figure 6 , at one end of the movable sleeve 82 away from the lower joint 83, there is a ring-shaped sealing portion 8203 adapted to the above-mentioned ring-shaped sealing groove 8104. In the butt joint state, the ring-shaped sealing portion 8203 is hermetically arranged in the ring-shaped sealing groove 8104, and the inner diameter of the ring-shaped sealing portion 8203 is not less than the inner diameter of the upper outlet 8103. At this time, the top surface of the ring-shaped sealing portion 8203 is in contact with the inner top surface of the ring-shaped sealing groove 8104 to improve the sealing performance between the upper joint 81 and the movable sleeve 82 after butt joint and prevent the medium from flowing out through the gap between the upper joint 81 and the movable sleeve 82. Of course, a ring-shaped sealing ring 810 can also be added between the outer wall of the ring-shaped sealing portion 8203 and the inner wall of the ring-shaped sealing groove 8104 to further improve the sealing performance.

[0086] Exemplarily, the ring-shaped sealing ring 810 is made of an elastic material. The ring-shaped sealing ring 810 can be fixedly arranged on the inner wall of the ring-shaped sealing groove 8104 or on the outer wall of the ring-shaped sealing portion 8203. No special limitation is made on the installation position and quantity of the ring-shaped sealing ring 810 here.

[0087] In addition, continue to refer to Figure 6 , on the outer wall of the movable sleeve 82, there is also a ring-shaped abutting portion 8204. The abutting portion 8204 is aligned with the bottom of the upper joint 81, and the outer diameter of the abutting portion 8204 is not less than the outer diameter of the bottom of the upper joint 81, so as to increase the contact area when the movable sleeve 82 abuts against the bottom of the upper joint 81.

[0088] Please refer to Figure 7 , inside the lower joint 83, there are also a lower sealing head 811, a lower guide post 812 and a lower fixing bracket 813.

[0089] Among them, the lower sealing head 811 is hermetically arranged in the lower inlet 8202. At this time, the outer wall of the lower sealing head 811 is in contact with the inner wall of the lower inlet 8202, so as to block the lower inlet 8202 through the lower sealing head 811 and prevent the medium from flowing out of the lower inlet 8202. At the same time, an annular lower sealing ring 814 is also arranged between the outer wall of the lower sealing head 811 and the inner wall of the lower inlet 8202 to further provide the sealing performance when the lower sealing head 811 seals the lower inlet 8202. It can be understood that the inner diameters of the upper outlet 8103 and the lower inlet 8202 are the same. At this time, the lower sealing head 811 is adapted to the upper sealing head 84, so that the lower sealing head 811 can enter the inner part of the upper diversion cavity 8101 through the upper outlet 8103.

[0090] Exemplarily, the lower sealing ring 814 is made of an elastic material. The lower sealing ring 814 can be fixedly arranged on the outer wall of the lower sealing head 811 or on the inner wall of the lower inlet 8202. There is no special limitation on the installation position and the number of the lower sealing rings 814.

[0091] For the automatic docking joint 8 provided in this embodiment, by adding the upper sealing ring 89, the lower sealing ring 814, the annular sealing part 8203 and the annular sealing ring 810, the automatic docking joint 8 still has a good sealing effect in the docking state, so as to improve the sealing performance of the automatic docking joint 8.

[0092] Continue to refer to Figure 7 , the lower fixing bracket 813 is fixedly connected to the inner wall of the lower diversion cavity 8301 to fix the lower fixing bracket 813 inside the lower diversion cavity 8301, and the lower fixing bracket 813 is provided with a notch for the medium to pass through. At the same time, one end of the lower guide post 812 is fixedly connected to the lower sealing head 811, and the other end of the lower guide post 812 is fixedly connected to the lower fixing bracket 813, so that the lower sealing head 811 is fixedly connected to the inner wall of the lower diversion cavity 8301 through the lower guide post 812 and the lower fixing bracket 813.

[0093] At the same time, a lower elastic body is also arranged between the movable sleeve 82 and the lower joint 83. At this time, the movable sleeve 82 and the lower joint 83 are connected through the lower elastic body to drive the lower joint 83 to move along the axis of the middle diversion cavity 8201 through the lower elastic body.

[0094] Specifically, continue to refer to Figure 7The lower elastic body includes a lower return spring 815, which is sleeved on the outer wall of the lower joint 83. At this time, one end of the lower return spring 815 is fixedly connected to the outer wall of the lower joint 83, and the other end of the lower return spring 815 is fixedly connected to the abutment portion 8204 of the movable sleeve 82. By arranging the lower return spring 815 on the outer wall of the lower joint 83, on the basis of driving the lower joint 83 to move along the axis of the middle guide cavity 8201, it is possible to avoid direct contact between the medium and the lower return spring 815, thereby increasing the service life of the lower return spring 815.

[0095] Continue to refer to Figure 2 The lifting mechanism includes a bracket 14 for supporting the container 11 and a lifting device for driving the bracket 14 to move closer to or away from the weighing device 12 in a vertical direction.

[0096] Please refer to Figure 10 The bracket 14 can be made of steel, and a downwardly recessed inner concave portion 1401 is provided on the bracket 14, and the container 11 is arranged in the inner concave portion 1401. The inner concave portion 1401 can provide a certain protection for the container 11, so as to avoid the container 11 from shaking and tipping over when the medium is introduced into the container 11.

[0097] Please refer to Figure 11 The bottom of the container 11 is fixedly provided with a carrying plate 18, and at this time, the carrying plate 18 is carried on the inner concave portion 1401 to support the container 11. At the same time, the area of ​​the carrying plate 18 is larger than the area of ​​the bottom of the container 11, so as to increase the contact area between the container 11 and the inner concave portion 1401 as much as possible, thereby using the inner concave portion 1401 to provide better support for the container 11.

[0098] Secondly, continue to refer to Figure 11 A support portion 19 is provided at the bottom of the carrying plate 18, and the support portion 19 extends downward in the vertical direction after passing through the inner recess 1401, so that when the bracket 14 approaches the weighing device 12 under the drive of the lifting device, the support portion 19 first contacts the weighing device 12 and supports the carrying plate 18, and as the lifting device continues to drive the bracket 14 to approach the weighing device 12, the bracket 14 can be separated from the container 11, and at this time the container 11 is independently carried on the weighing device 12. Of course, in actual implementation, the support portion 19 can also be directly provided at the bottom of the container 11, and the carrying plate 18 is omitted.

[0099] For example, there are at least two support parts 19 disposed at the bottom of the carrier plate 18. When there are two support parts 19, the two support parts 19 are symmetrically disposed to support the container 11. In this embodiment, there are four support parts 19, which are distributed around the carrier plate 18 to better support the container 11. At the same time, a buffer pad (not shown in the figure) can be disposed at the bottom of the support part 19 to play a certain buffering role.

[0100] It is understandable that the support portion 19 may adopt a screw foot with adjustable height, so that the length of the support portion 19 can be adjusted as needed, thereby adjusting the length of the support portion 19 extending out of the inner recess 1401 .

[0101] Continue to refer to Figure 2 The lifting device in this embodiment includes a driving motor 120, a transmission device and a screw lift 121. The driving motor 120 is connected to the screw lift 121 through the transmission device, and the output end of the screw lift 121 is connected to the bracket 14.

[0102] For example, in order to improve the stability of the bracket 14 during movement, four screw lifts 121 are provided in this embodiment, and the four screw lifts 121 are respectively provided around the bracket 14 .

[0103] Continue to refer to Figure 2 The transmission device includes a transmission gear box 122 and a transmission shaft 123 . The drive motor 120 is connected to two of the screw lifts 121 through the transmission gear box 122 , and the remaining two adjacent screw lifts 121 are connected to each other through the transmission shaft 123 .

[0104] When the driving motor 120 is working, the driving motor 120 drives two of the screw lifts 121 to work through the transmission gear box 122 to push the bracket 14; at the same time, the remaining screw lifts 121 also start to work and push the bracket 14 under the transmission action of the transmission shaft 123, thereby realizing the use of one driving motor 120 to drive four screw lifts 121 to work and push the bracket 14 from four directions, saving manufacturing costs while improving the stability of the bracket 14 during movement.

[0105] It should be noted that the above-mentioned lifting device can also be replaced by a conventional linear drive device, such as a cylinder, a hydraulic cylinder or an electric push rod, etc. The specific type of the lifting device is not particularly limited here.

[0106] In order to more clearly understand the present invention, the working principle of the weighing device 1 when the flow meter 3 to be measured is evaluated by weighing method using the cryogenic liquid flow performance testing system will be further described below.

[0107] Before weighing and metering, the lifting device of the jacking mechanism drives the bracket 14 to move upward, so as to drive the container 11 away from the weighing device 12. At this time, the container 11 drives the first pipeline 16, the lower joint 83 and the movable sleeve 82 to move upward together. When the annular sealing part 8203 of the movable sleeve 82 extends into the annular sealing groove 8104 of the upper joint 81 and the top surface of the abutting part 8204 abuts against the bottom of the upper joint 81, the movable sleeve 82 stops moving; at this time, the bracket 14 continues to drive the container 11 to move upward under the drive of the lifting device, so that the lower joint 83 continues to approach the upper joint 81, the lower return spring 815 contracts to store a elastic force, and the lower sealing head 811 extends into the upper outlet 8103 of the upper joint 81 under the drive of the lower joint 83 and pushes the upper sealing head 84 away from the lower joint 83 until both the upper sealing head 84 and the lower sealing head 811 completely enter the upper diversion cavity 8101. At this time, the medium in the upper diversion cavity 8101 flows from the gap between the upper sealing head 84 and the inner wall of the upper diversion cavity 8101 to the upper outlet 8103 and finally enters the lower diversion cavity 8301. Thus, the upper diversion cavity 8101, the upper outlet 8103, the lower inlet 8202, the middle diversion cavity 8201 and the lower diversion cavity 8301 are connected in sequence, and the connection and conduction of the first pipeline 16 and the second pipeline 17 are realized. At this time, the internal structure of the automatic docking joint 8 is as shown in Figure 9 shown.

[0108] Subsequently, the medium is transported into the container 11 through the second pipeline 17 and the first pipeline 16. After a certain period of time, the lifting device of the jacking mechanism drives the bracket 14 to move downward, so as to drive the container 11 to move downward through the bracket 14. At this time, the container 11 drives the first pipeline 16 and the lower joint 83 to move downward. As the container 11 moves downward continuously, the lower joint 83 gradually moves away from the upper joint 81. When the lower sealing head 811 completely exits from the upper joint 81, the upper sealing head 84 automatically resets under the action of the upper return spring 85 to re-seal the upper outlet 8103; as the lower joint 83 continues to move, the movable sleeve 82 automatically resets under the action of the lower return spring 815. At this time, the lower sealing head 811 re-seals the lower inlet 8202 of the movable sleeve 82. Thus, the connection between the first pipeline 16 and the second pipeline 17 is disconnected. At this time, the internal joint of the automatic docking joint 8 is as shown in Figure 8 shown.

[0109] Finally, the lifting device is used to drive the bracket 14 to descend, so as to drive the container 11 closer to the weighing device 12. When the supporting part 19 arranged at the bottom of the container 11 contacts the weighing device 12, the supporting part 19 independently supports the container 11 on the weighing device 12. As the lifting device continues to drive the bracket 14 to move downward, the bracket 14 will be completely separated from the container 11, and then the weighing measurement can be started. Since the container 11 is only independently borne on the weighing device 12 during the weighing stage, only the container 11 and the medium inside it are weighed and measured during the weighing stage. Therefore, compared with the existing weighing device 1, the accuracy of weighing and measurement can be further improved, providing more accurate data support for the subsequent verification and comparison of the measured flow meter 3.

[0110] It can be seen that in this embodiment, by adding an automatic docking joint 8 and a jacking mechanism to the weighing device 1, the rapid conduction or disconnection of the first pipeline 16 and the second pipeline 17 can be realized, and the medium can be effectively prevented from flowing out of the pipeline after the two pipelines are disconnected. At the same time, during the weighing and measurement stage, the container 11 is independently borne on the weighing device 12, so that only the container 11 and the medium inside it are weighed and measured during the weighing stage. Therefore, compared with the existing weighing device 1, the accuracy of weighing and measurement can be further improved, providing more accurate data support for the subsequent verification of the measured flow meter 3.

[0111] It should be noted that, continuing to refer to Figure 1 and Figure 2 , in actual implementation, a third pipeline 124 extending in the vertical direction can also be added to the container 11, and a fourth pipeline 125 communicating with the storage tank 7 is added at the same time. The third pipeline 124 and the fourth pipeline 125 are also connected through the above-mentioned automatic docking joint 8. At this time, the third pipeline 124 and the fourth pipeline 125 are used as return pipes, so that after the weighing and measurement are completed, the medium in the container 11 can flow back into the storage tank 7 through the third pipeline 124 and the fourth pipeline 125, realizing the recycling of the medium.

[0112] Embodiment 2

[0113] On the basis of Embodiment 1, this embodiment provides a low-temperature liquid flow performance test method to realize more accurate verification of the measured flow meter 3. Among them, this test method adopts the low-temperature liquid flow performance test system described in Embodiment 1 above. The test method can be divided into the standard meter method and the weighing method. The specific test processes of the standard meter method and the weighing method will be further elaborated below.

[0114] When calibrating using the standard meter method, first disconnect the pipeline between the commutator 2 and the container 11 of the weighing device 1. At this time, the medium flowing out of the storage tank 7 can flow through the submersible pump 6, the gas-liquid separator 5, the standard flow meter 4, the measured flow meter 3, and the commutator 2 in sequence and then flow back into the storage tank 7.

[0115] When the medium flow rate in the pipeline is stable, and the temperature, pressure, and heat exchange are relatively balanced, the standard flow meter 4 and the measured flow meter 3 are used to simultaneously collect and calculate the mass flow rate of the medium in the current pipeline within a unit time period, and the mass flow rate measured by the standard flow meter 4 is compared with the mass flow rate measured by the measured flow meter 3, so as to determine whether the measurement accuracy of the measured flow meter 3 meets the requirements. Thus, one calibration using the standard meter method is completed.

[0116] Before performing the calibration using the weighing method, first use the lifting device of the lifting mechanism to drive the bracket 14 downward, so that the container 11 is carried on the weighing scale 12, and the indication value of the weighing scale 12 is reset to zero to remove the initial mass of the container 11. Subsequently, disconnect the pipeline between the commutator 2 and the storage tank 7. When the container 11 moves upward driven by the bracket 14 of the lifting mechanism and the first pipeline 16 and the second pipeline 17 are connected and conducted through the automatic docking joint 8, and the third pipeline 124 and the fourth pipeline 125 are also connected and conducted through the automatic docking joint 8, at this time, the medium flowing out of the storage tank 7 can flow through the submersible pump 6, the gas-liquid separator 5, the standard flow meter 4, the measured flow meter 3, the commutator 2, and the container 11 in sequence and then flow back into the storage tank 7.

[0117] Meanwhile, the medium should first be circulated in the above-mentioned cryogenic liquid flow performance test system at a mass flow rate B, and the circulation time should be no less than 10 minutes to pre-cool the test system and improve the accuracy of the calibration result. Assuming that the maximum mass flow rate of the medium flowing in the pipeline of the above-mentioned cryogenic liquid flow performance test system is A, then the above-mentioned mass flow rate B should be greater than half of the maximum mass flow rate A. After the test system is pre-cooled and the medium in the container 11 is emptied, close the valve between the fourth pipeline 125 and the storage tank 7, and start the calibration using the weighing method. It should be noted that since the third pipeline 124 and the fourth pipeline 125 are also conducted at this time, closing the valve on the fourth pipeline 125 can prevent the medium from flowing back into the storage tank 7.

[0118] At this time, the medium enters the container 11 through the second pipeline 17 and the first pipeline 16, and the mass flow rate of the medium in the pipeline is detected in real time by the flow meter 3 to be measured. After a certain period of time, the mass flow rate measured by the flow meter 3 to be measured during this period is recorded, and at the same time, the commutator 2 is controlled to communicate with the storage tank 7, and the medium flows back from the commutator 2 to the storage tank 7. Subsequently, the container 11 moves vertically close to the weighing device 12 driven by the bracket 14 of the lifting mechanism. At this time, the automatic docking joints 8 between the first pipeline 16 and the second pipeline 17 and the automatic docking joints 8 between the third pipeline 124 and the fourth pipeline 125 are all disconnected; after the container 11 is carried on the weighing device 12 and the lifting mechanism is completely separated from the container 11, the mass of the medium in the container 11 at this time is obtained by weighing and measuring with the weighing device 12. Furthermore, the mass flow rate within a unit time period can be calculated through this mass, and by comparing this mass flow rate with the mass flow rate measured by the flow meter 3 to be measured, it can be determined whether the measurement accuracy of the flow meter 3 to be measured meets the requirements. Thus, one verification by the weighing method is completed.

[0119] It can be seen from this that the testing method provided in this embodiment uses the weighing device 1 described in Embodiment 1 above to perform verification by the weighing method, which can improve the accuracy of the weighing and measurement results during the weighing and measurement stage compared with the prior art, and thus improve the accuracy of the final verification result.

[0120] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A cryogenic liquid flow performance testing system, including a weighing device, characterized in that , the weighing device includes: a container; a first pipeline, one end of the first pipeline is communicated with the container, and the other end of the first pipeline extends vertically and is connected with an automatic docking joint; a second pipeline, one end of the second pipeline is communicated with the first pipeline through the automatic docking joint; a weighing scale, arranged below the container; and, a lifting mechanism, the lifting mechanism is used to drive the container to approach or move away from the weighing scale vertically; wherein, when the container is borne on the weighing scale, the lifting mechanism is completely separated from the container, and the automatic docking joint is disconnected; when the container moves away from the weighing scale, the first pipeline and the second pipeline are connected and conducted through the automatic docking joint; the automatic docking joint includes: an upper joint, with an upper diversion cavity and an upper outlet arranged inside; the upper diversion cavity penetrates through the upper joint, the upper outlet is communicated with the upper diversion cavity, and the inner diameter of the upper outlet is smaller than the inner diameter of the upper diversion cavity; and, an upper sealing head, hermetically arranged in the upper outlet; an upper elastic body, the upper sealing head is connected with the inner wall of the upper diversion cavity through the upper elastic body, and the upper elastic body is used to drive the upper sealing head to move along the axis of the upper diversion cavity; and, a lower joint, with a lower diversion cavity arranged inside; the lower diversion cavity penetrates through the lower joint; and, a movable sleeve, located between the upper joint and the lower joint; the movable sleeve is slidably connected with the lower joint, a middle diversion cavity and a lower inlet are arranged inside the movable sleeve, the middle diversion cavity penetrates through the movable sleeve and is communicated with the lower diversion cavity, and the lower inlet is communicated with the middle diversion cavity; and, a lower sealing head, hermetically arranged in the lower inlet; the lower sealing head is adapted to the upper sealing head, and the lower sealing head is connected with the inner wall of the lower diversion cavity; and, a lower elastic body, the movable sleeve and the lower joint are connected through the lower elastic body, so as to drive the lower joint to move along the axis of the middle diversion cavity through the lower elastic body; wherein, the first pipeline is communicated with the lower joint, and the second pipeline is communicated with the upper joint; one end of the upper joint is provided with an annular sealing groove communicated with the upper outlet, one end of the movable sleeve away from the lower joint is provided with an annular sealing portion adapted to the annular sealing groove, the annular sealing portion is hermetically arranged in the annular sealing groove, the inner diameter of the annular sealing portion is not less than the inner diameter of the upper outlet, and an annular sealing ring is arranged between the outer wall of the annular sealing portion and the inner wall of the annular sealing groove; one end of the movable sleeve away from the lower inlet extends into the lower diversion cavity and is slidably connected with the lower joint; the outer wall of the movable sleeve is provided with an annular abutting portion, the annular abutting portion is aligned with the bottom of the upper joint, and the outer diameter of the annular abutting portion is not less than the outer diameter of the bottom of the upper joint; The lower elastomer includes a lower return spring sleeved on the outer wall of the lower joint. One end of the lower return spring is connected to the lower joint, and the other end of the lower return spring is connected to the abutting portion.

2. The cryogenic liquid flow performance testing system according to claim 1, wherein, an upper sealing ring is provided between the outer wall of the upper sealing head and the inner wall of the upper outlet, and a lower sealing ring is provided between the outer wall of the lower sealing head and the inner wall of the lower inlet.

3. The cryogenic liquid flow performance testing system according to claim 1, wherein, a fixing cylinder, an upper guiding column and an upper fixing bracket are arranged inside the upper diversion cavity. A reset cavity is arranged inside the fixing cylinder. The axis of the reset cavity coincides with the axis of the upper diversion cavity. A through hole communicating with the reset cavity is arranged on the fixing cylinder, and the through hole is adapted to the upper guiding column; one end of the upper guiding column is connected to the upper sealing head, and the other end of the upper guiding column extends axially along the upper diversion cavity into the reset cavity; the upper fixing bracket is provided with a notch, and the fixing cylinder is connected to the inner wall of the upper diversion cavity through the upper fixing bracket; the upper elastomer includes an upper return spring sleeved on the outer wall of the upper guiding column. One end of the upper return spring is connected to the upper guiding column, and the other end of the upper return spring is connected to the inner wall of the reset cavity.

4. The cryogenic liquid flow performance testing system according to claim 1, wherein, a lower guiding column and a lower fixing bracket are arranged inside the lower diversion cavity. One end of the lower guiding column is connected to the lower sealing head, and the other end of the lower guiding column is connected to the lower fixing bracket. The lower fixing bracket is provided with a notch, and the lower fixing bracket is connected to the inner wall of the lower diversion cavity.

5. The cryogenic liquid flow performance testing system according to claim 1, wherein, the lifting mechanism includes: a bracket for supporting the container; and, a lifting device for driving the bracket to approach or move away from the weighing device in the vertical direction; wherein, a supporting portion is arranged on the container and extends downward vertically through the bracket.

6. The cryogenic liquid flow performance testing system according to claim 5, wherein, a downwardly concave inner concave portion is arranged on the bracket, and the container is arranged inside the inner concave portion; a bearing plate is arranged at the bottom of the container. The area of the bearing plate is larger than the area of the bottom of the container. The bearing plate bears on the inner concave portion, and the supporting portion is arranged on the bearing plate and passes through the inner concave portion.

7. A cryogenic liquid flow performance testing method, using the cryogenic liquid flow performance testing system according to any one of claims 1-6 to calibrate the flow meter under test, wherein, it includes the following steps: Before weighing and metering, the lifting mechanism drives the container to move away from the weighing device in the vertical direction, so that the first pipeline and the second pipeline are connected and conducted through the automatic docking joint; Subsequently, a medium is introduced into the container through the first pipeline and the second pipeline; after a certain period of time, the jacking mechanism drives the container to approach the weighing device in the vertical direction; At this time, the automatic docking joint between the first pipeline and the second pipeline disconnects and disengages; After the container is carried on the weighing device and the jacking mechanism is completely disengaged from the container, the weighing device can be used to start weighing and metering.

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