Independent testing mechanism for cleaned cold core

Abstract

The utility model discloses an independent testing mechanism for a cleaned cold core, which comprises a cold core placing cylinder, the interior of the cold core placing cylinder is designed to be of a hollow structure, a cylinder cover is fixedly arranged on the outer wall of one side of the cold core placing cylinder through a fixing bolt, and a first screwed joint is fixedly arranged on the outer wall of one side of the cylinder cover; a second threaded connector is fixedly installed in the center of the outer wall of the side, away from the barrel cover, of the cold core containing barrel, the first threaded connector is in threaded connection with an air inlet pipeline, a pump body is installed on the air inlet pipeline, a pressure gauge used for detecting air pressure is installed on the pump body, and the second threaded connector is in threaded connection with an air outlet pipeline. According to the utility model, by detecting and recording pressure values, temperature values and flow values when the cold core is tested at different time points, a floating curve for testing at multiple time points can be formed, so that whether the cleaned cold core is qualified or not can be judged through the floating numerical curve, and the performance test work of the cleaned cold core can be independently completed.

Description

Technical Field

[0001] The utility model relates to the technical field of cold heads of magnetic resonance systems, in particular to an independent testing mechanism after a cold core is cleaned. Background Art

[0002] Single-stage refrigeration can achieve temperatures above 10K, such as 77K, which is used to liquefy nitrogen, which also plays an important role in the field of magnetic resonance. Because of its low price, it is often used to pre-cool magnets to save expensive liquid helium;

[0003] However, single-stage refrigeration cannot reduce the temperature below 10K, and two-stage refrigeration is required. The cold head of magnetic resonance is essentially a two-stage expander. The general idea of ​​refrigeration is as follows: the cold head and the helium compressor form a closed circulation system, and the two are connected by two helium tubes. The cold head drives the piston through a motor to expand the high-pressure helium in the cold head to take away the heat of the helium in the magnet (such as a 4K cold head, which turns helium into liquid helium). Then the high-pressure and low-temperature helium is turned into low-pressure and high-temperature helium, which returns to the helium compressor for another cycle.

[0004] However, the mechanical movement and friction of the helium compressor will drop dust, and the dust in the helium is filtered through the first-level cold core. After a long time, the dust accumulates, causing the refrigeration effect to weaken, and the first-level cold core needs to be disassembled for cleaning and inspection. The existing first-level cold core needs to be tested for performance after cleaning. However, the existing performance test work can only reinstall the cleaned or repaired cold core and the cold head, and then put the cold head and the cold core into the cold head test rack for unified testing. The assembly and disassembly process of the cold core and the cold head is relatively cumbersome, which reduces the detection efficiency and affects normal use. In actual implementation, there is no independent cold core test structure, which is extremely inconvenient. For this reason, the utility model proposes a structure that can independently perform performance testing on the cleaned cold core. Utility Model Content

[0005] The utility model aims to provide an independent testing mechanism for cold core after cleaning, so as to solve the problems raised in the above background technology.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: an independent testing mechanism for the cold core after cleaning, comprising a cold core placing tube, the interior of the cold core placing tube is a hollow structure design, a tube cover is fixedly installed on the outer wall of one side of the cold core placing tube by fixing bolts, a No. 1 threaded joint is fixedly installed on the outer wall of one side of the tube cover, a No. 2 threaded joint is fixedly installed at the center position of the outer wall of the side of the cold core placing tube away from the tube cover, the No. 1 threaded joint is threadedly connected to an air inlet pipe, a pressure gauge for gas pressure detection is installed on the air inlet pipe, the No. 2 threaded joint is threadedly connected to an air outlet pipe, a flow meter is installed on the air outlet pipe, and a temperature sensor is installed on the side of the cold core placing tube close to the No. 2 threaded joint.

[0007] Preferably, a diversion groove is provided at the center of the inner wall of the cylinder cover, and the diversion groove adopts a triangular structure design.

[0008] Preferably, an "O"-shaped groove is provided on the inner wall of the cold core placement tube close to the tube cover, an O-shaped sealing ring is installed in the O-shaped groove, and the cold core placement tube is sealed and connected to the tube cover via the O-shaped sealing ring.

[0009] Preferably, the cold core placement tube, the air outlet pipe and the air inlet pipe are designed to be interconnected.

[0010] Compared with the prior art, the beneficial effects of the utility model are:

[0011] The cold core testing mechanism designed by the utility model detects and records the pressure value, temperature value and flow value when the cold core is tested at different time points, so as to form a floating curve of tests at multiple time points, so that it can be judged whether the cold core after cleaning is qualified through the floating numerical curve, so that the performance test of the cold core after cleaning can be completed independently, and there is no need to assemble and test the cold core and the cold head as a whole, thereby reducing one assembly and disassembly test process, thereby effectively improving the testing efficiency of the cold core, and avoiding the tedious assembly and disassembly process of the cold core and the cold head, effectively reducing the labor intensity. The utility model has the use effect of independent cold core detection, is easy to use, and has quick assembly and convenient disassembly between structures, and is suitable for popularization and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram of the overall structure of the testing mechanism of an embodiment of the utility model;

[0013] Figure 2 This is a schematic diagram of the external structure of the cold core placement cylinder of an embodiment of the utility model;

[0014] Figure 3 It is a schematic diagram of the inner structure of the cylinder cover according to an embodiment of the utility model.

[0015] In the figure: 1. Cold core placement cylinder; 2. Cylinder cover; 3. Diverter groove; 4. No. 1 threaded joint; 5. No. 2 threaded joint; 6. Temperature sensor; 7. Air outlet pipe; 8. Air inlet pipe; 9. Pressure gauge; 10. Flow meter. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0017] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0018] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0019] See also Figure 1-3 The utility model provides an embodiment: an independent testing mechanism for cold core after cleaning, including a cold core placement tube 1, the interior of the cold core placement tube 1 is a hollow structure design, the cold core placement tube 1 can place the cleaned cold core, a tube cover 2 is fixedly installed on the outer wall of one side of the cold core placement tube 1 by fixing bolts, the tube cover 2 can seal the cold core placement tube 1, a No. 1 threaded joint 4 is fixedly installed on the outer wall of one side of the tube cover 2, and a No. 2 threaded joint 5 is fixedly installed at the center position of the outer wall of the side of the cold core placement tube 1 away from the tube cover 2, and the No. 1 threaded joint 4 and the No. 2 threaded joint 5 can be threadedly connected with the external structure, and in actual use, the overall assembly and disassembly of the testing mechanism can be convenient, and it is easy to use;

[0020] The No. 1 threaded joint 4 is threadedly connected with an inlet pipe 8, on which a pressure gauge 9 for gas pressure detection is installed, and the No. 2 threaded joint 5 is threadedly connected with an outlet pipe 7, on which a flow meter 10 for gas flow detection is installed. In actual use, the tail end of the inlet pipe 8 can be connected to an external helium tank, so that helium is injected through the pump body;

[0021] A temperature sensor 6 is installed on the side of the cold core placement tube 1 close to the second threaded joint 5, and the temperature of the gas after passing through the cold core can be measured by the temperature sensor 6;

[0022] Among them, the cold core placement tube 1, the air outlet pipe 7, and the air inlet pipe 8 are interconnected in structure design;

[0023] According to the above structure, one end of the air inlet pipe 8 can be connected to an external helium tank, so that helium can be injected through the pump body. When the performance test of the cleaned or repaired cold core needs to be performed, the cold core placement tube 1 can be opened through the tube cover 2, and the cold core to be tested can be placed inside the cold core placement tube 1 (when placed, the air inlet end of the cold core faces the air inlet pipe 8), and then the end of the cold core placement tube 1 is connected and sealed through the tube cover 2 to ensure the internal sealing and improve the quality of subsequent tests;

[0024] During the test, the helium in the external helium tank is delivered to the inside of the air inlet pipe 8 by the external delivery pump, and the helium pressure can be detected by the set pressure gauge 9. The helium flowing through the pressure gauge 9 enters the inside of the cold core placement tube 1 through the No. 2 threaded joint 5. The helium is cooled after passing through the cold core, and then reaches the tail of the cold core placement tube 1. At this time, the temperature of the helium after the cold core is cooled can be detected by the set temperature sensor 6;

[0025] After the temperature detection, the helium is discharged through the cylinder cover 2 and the No. 1 threaded joint 5, and enters the outlet pipe 7. A flow meter 10 is installed on the outlet pipe 7, and the flow rate of the helium passing through can be detected by the flow meter 10, and finally discharged through the outlet pipe 7;

[0026] In this way, cyclic detection work is carried out at different time points through the above detection method, and the pressure value, temperature value and flow value measured at each time point are recorded, the values ​​at multiple time points are collected to form a floating curve, and the performance of the cold core after cleaning is evaluated according to the floating degree of the curve, so as to effectively complete the independent detection effect of the cold core performance.

[0027] In this embodiment, in order to facilitate the diversion work, a diversion groove 3 is opened at the center of the inner wall of the cylinder cover 2. The diversion groove 3 adopts a triangular structure design. The triangular diversion groove 3 can perform triangular diversion processing when the helium passes through the cylinder cover 2, which facilitates the gas diversion work.

[0028] In this embodiment, in order to improve the structural sealing between the cold core placement tube 1 and the tube cover 2 and avoid helium leakage, an "O"-shaped groove is opened on the inner wall of the cold core placement tube 1 close to the tube cover 2, and an O-shaped sealing ring is installed in the O-shaped groove. The cold core placement tube 1 is sealed and connected to the tube cover 2 through the O-shaped sealing ring.

[0029] Working principle: In actual use, one end of the air inlet pipe 8 can be connected to an external helium tank, so that helium can be injected through the pump body. When the performance test of the cleaned or repaired cold core is required, the cold core placement tube 1 can be opened through the tube cover 2, and the cold core to be tested can be placed inside the cold core placement tube 1 (when placed, the air inlet end of the cold core faces the air inlet pipe 8), and then the end of the cold core placement tube 1 is connected and sealed through the tube cover 2 to ensure the internal sealing and improve the quality of subsequent tests;

[0030] During the test, the helium in the external helium tank is delivered to the inside of the air inlet pipe 8 by the external delivery pump, and the helium pressure can be detected by the set pressure gauge 9. The helium flowing through the pressure gauge 9 enters the inside of the cold core placement tube 1 through the No. 2 threaded joint 5. The helium is cooled after passing through the cold core, and then reaches the tail of the cold core placement tube 1. At this time, the temperature of the helium after the cold core is cooled can be detected by the set temperature sensor 6;

[0031] After the temperature detection, the helium is discharged through the cylinder cover 2 and the No. 1 threaded joint 5, and enters the outlet pipe 7. A flow meter 10 is installed on the outlet pipe 7, and the flow rate of the helium passing through can be detected by the flow meter 10, and finally discharged through the outlet pipe 7;

[0032] In this way, the above detection method is used to perform cyclic detection work at different time points, and the pressure value, temperature value and flow value measured at each time point are recorded, and the values ​​at multiple time points are collected to form a floating curve. The performance of the cold core after cleaning is evaluated according to the floating degree of the curve, so as to effectively complete the independent detection effect of the cold core performance;

[0033] The utility model provides a No. 1 threaded joint 4 and a No. 2 threaded joint 5 on the cylinder cover 2 and the cold core placement cylinder 1 respectively, and the No. 1 threaded joint 4 and the No. 2 threaded joint 5 can be threadedly connected with the air inlet pipe 10 and the air outlet pipe 7 to ensure the normal circulation of helium. At the same time, the threaded connection method can facilitate the overall assembly and disassembly of the test mechanism, which is more convenient to use.

[0034] To sum up, the cold core testing mechanism designed in the utility model can form a floating curve of multiple time point tests by detecting and recording the pressure value, temperature value and flow value during the cold core test at different time points, so as to judge whether the cold core after cleaning is qualified through the floating numerical curve, so as to independently complete the performance test of the cold core after cleaning, and there is no need to assemble and test the cold core and the cold head as a whole, thereby reducing one assembly and disassembly test process, thereby effectively improving the testing efficiency of the cold core, and avoiding the cumbersome assembly and disassembly process of the cold core and the cold head, effectively reducing labor intensity. The utility model has the use effect of independent cold core detection, is easy to use, and has quick assembly and disassembly between structures, and is suitable for popularization and use.

[0035] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

Claims

1. An independent testing mechanism after cold core cleaning, comprising a cold core placement cylinder (1), characterized in that: The interior of the cold core placement tube (1) is designed as a hollow structure. A tube cover (2) is fixedly installed on the outer wall of one side of the cold core placement tube (1) by fixing bolts. A No. 1 threaded joint (4) is fixedly installed on the outer wall of one side of the tube cover (2). A No. 2 threaded joint (5) is fixedly installed at the center position of the outer wall of the cold core placement tube (1) away from the tube cover (2). The No. 1 threaded joint (4) is threadedly connected to an air intake pipe (8). A pressure gauge (9) for gas pressure detection is installed on the air intake pipe (8). An air outlet pipe (7) is threadedly connected to the No. 2 threaded joint (5). A flow meter (10) is installed on the air outlet pipe (7). A temperature sensor (6) is installed on the side of the cold core placement tube (1) close to the No. 2 threaded joint (5).

2. The independent testing mechanism after cold core cleaning according to claim 1, characterized in that: A flow-dividing groove (3) is provided at the center of the inner wall of the cylinder cover (2), and the flow-dividing groove (3) is designed in a triangular structure.

3. The independent testing mechanism after cold core cleaning according to claim 1, characterized in that: An "O"-shaped groove is provided on the inner wall of the cold core placement cylinder (1) on one side close to the cylinder cover (2), an O-shaped sealing ring is installed in the O-shaped groove, and the cold core placement cylinder (1) is sealedly connected to the cylinder cover (2) via the O-shaped sealing ring.

4. The independent testing mechanism after cold core cleaning according to claim 1, characterized in that: The cold core placement cylinder (1), the air outlet pipe (7) and the air inlet pipe (8) are designed to be interconnected.

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