Mixed refrigeration double-station rapid cooling low-temperature tank device

Abstract

The utility model discloses a mixed refrigeration double-station rapid cooling low-temperature tank device. A station of a liquid nitrogen cooling system and a station of an alcohol cooling system are integrated on a main machine; a pressure reducing valve of a self-pressurization liquid nitrogen tank of the liquid nitrogen cooling system is electrically connected with a port of an electromagnetic valve on the liquid nitrogen refrigerating system, and the port of the electromagnetic valve is electrically connected with a liquid nitrogen switch group arranged on the outer wall of a main body machine; the self-pressurization liquid nitrogen tank is communicated with the liquid nitrogen low-temperature freezing sample bin through a pressure reducing valve and an electromagnetic valve and a temperature adjusting flow pipe which are sequentially mounted on a pipeline; a first high-precision PT100 temperature sensor is mounted in the liquid nitrogen low-temperature freezing sample bin; the alcohol cooling system comprises an alcohol low-temperature freezing sample bin, a second high-precision PT100 temperature sensor is mounted in the alcohol low-temperature freezing sample bin, a stirrer is mounted at the upper part of the alcohol low-temperature freezing sample bin, and a cascade compressor refrigerating system is mounted at the outer lower part of the alcohol low-temperature freezing sample bin; according to the utility model, diversified requirements on accurate temperature control, rapid cooling and continuous temperature regulation in scientific experiments, material tests or industrial production can be met.

Description

Technical Field

[0001] The utility model relates to the field of cooling and heat preservation of specimens in impact tests and other low-temperature detection fields, and specifically relates to a hybrid refrigeration double-station rapid cooling low-temperature tank device. Background Technique

[0002] During the use of metal materials, in addition to having sufficient strength and plasticity, they are also required to

[0003] have sufficient toughness. Toughness refers to the ability of a metal material to absorb energy during elastic deformation, plastic deformation, and fracture processes, that is, the ability of the material to resist the action of impact loads without being damaged. Therefore, parts that bear impact loads must have sufficient toughness. The most commonly used method to evaluate the toughness of metal materials is the Charpy pendulum impact test method for metal materials, namely GB / T 229-2020 "Metallic materials - Charpy pendulum impact test method" and ASTM E23-23a "Standard test method for notched bar impact testing of metallic materials", and the cooling and heat preservation of specimens during the test are involved in this method.

[0004] Clause 8.3 in GB / T 229-2020 "Metallic materials - Charpy pendulum impact test method" only specifies the test temperature, and does not specify the cooling device during the test and how to cool.

[0005] Currently, there are various specimen cooling and heat preservation devices in impact tests on the market, with different structural designs. The low-temperature tanks can be mainly classified into two categories:

[0006] First, the type that uses pure liquid nitrogen as the cooling medium. Such low-temperature tanks have the significant problem of overly long manual temperature adjustment time, and at the same time, there is a large evaporation amount, resulting in significant energy waste.

[0007] Second, the low-temperature tanks that use alcohol or aviation gasoline as the single cooling medium. They rely on a single small-power compressor for refrigeration, so the cooling efficiency is low, and alcohol is easy to volatilize, further increasing the use cost and maintenance difficulty.

[0008] If customers want to quickly and energy-efficiently achieve continuous temperature adjustment from room temperature to -196°C, they must purchase two low-temperature tanks with different cooling media, which have high manufacturing costs, waste energy, occupy a large space, and have high procurement costs, etc. Content of the Utility Model

[0009] The utility model provides a hybrid refrigeration double-station rapid cooling low-temperature tank device, which can meet the diverse requirements for precise temperature control, rapid cooling, and continuous temperature adjustment in scientific experiments, material testing, or industrial production.

[0010] To solve the above technical problems, the technical solutions adopted by the utility model are as follows:

[0011] A hybrid refrigeration double-station rapid cooling low-temperature bath device, comprising a liquid nitrogen cooling system, an alcohol cooling system and a PID intelligent temperature control system. The low-temperature bath integrates the stations of the liquid nitrogen cooling system and the alcohol cooling system on a main body machine; the liquid nitrogen cooling system includes a self-pressurizing liquid nitrogen tank, the pressure reducing valve of the self-pressurizing liquid nitrogen tank is electrically connected to the solenoid valve port on the liquid nitrogen refrigeration system, and the solenoid valve port is electrically connected to the liquid nitrogen switch group arranged on the outer wall of the main body machine; the self-pressurizing liquid nitrogen tank is communicated with a liquid nitrogen low-temperature freezing sample chamber through a pressure reducing valve and a solenoid valve, a temperature regulating flow tube and a pipeline installed in sequence, and a first high-precision PT100 temperature sensor is installed in the liquid nitrogen low-temperature freezing sample chamber. The solenoid valve, the liquid nitrogen switch group, the first high-precision PT100 temperature sensor and the PID intelligent temperature control system are electrically connected; the alcohol cooling system includes an alcohol low-temperature freezing sample chamber, in which a second high-precision PT100 temperature sensor is installed. A stirrer is installed on the upper part of the alcohol low-temperature freezing sample chamber, and a cascade compression refrigeration system is installed on the lower outer part, that is, the lower part of the main body machine. The cascade compression refrigeration system is used to adjust and control the temperature in the alcohol low-temperature freezing sample chamber; the cascade compression refrigeration system, the second high-precision PT100 temperature sensor and the stirrer are all electrically connected to the PID intelligent temperature control system, and the control switch group of the cascade compression refrigeration system is installed on the outer wall of the main body machine; the liquid nitrogen low-temperature freezing sample chamber and the alcohol low-temperature freezing sample chamber are arranged in parallel on the upper part of the main body machine.

[0012] The liquid nitrogen low-temperature freezing sample chamber and the alcohol low-temperature freezing sample chamber are made of heat-insulating materials.

[0013] The size of the main body machine is: 96cm × 59cm × 78cm.

[0014] The utility model integrates two independent cooling control systems, which do not interfere with each other and can cool samples simultaneously, greatly improving work efficiency. It can meet the diverse requirements for precise temperature control, rapid cooling and continuous temperature adjustment in scientific experiments, material testing or industrial production. Moreover, it can continuously adjust the temperature in the range from room temperature to -196°C, and finally make the cooling and heat preservation of the samples uniform and stable. It helps to improve test efficiency, reduce operation costs and reduce resource waste. Starting from the idea of learning from the common cooling methods of impact samples and meeting the requirements of test standards, the problem of continuously variable rapid temperature control is solved.

[0015] The cooling workpiece of the utility model meets the requirements of GB / T 229-2020 "Metallic materials - Charpy pendulum impact test method" and ASTM E23-23a "Standard test method for notch bar impact testing of metallic materials", and is applicable to the cooling and heat preservation of impact samples. Description of the drawings

[0016] Figure 1 is a schematic structural view of the present utility model;

[0017] Figure 1 In the figure: 1. Liquid nitrogen system temperature display screen, 2. Liquid nitrogen switch group, 3. Liquid nitrogen low-temperature freezing sample chamber, 4. First high-precision PT100 temperature sensor, 5. Main body machine, 6. Stirrer, 7. Alcohol low-temperature freezing sample chamber, 8. Alcohol system temperature control screen, 9. Control switch group, 10. Cascade compression refrigeration system, 11. Pressure reducing valve, 12. Self-pressurizing liquid nitrogen tank, 13. Second high-precision PT100 temperature sensor, 14. Temperature regulating flow tube, 15. Solenoid valve, 16. Ferrule type straight tube joint. Specific embodiments

[0018] The present utility model will be further described in detail below with reference to the accompanying drawings.

[0019] Refer to Figure 1 , a hybrid refrigeration double-station rapid cooling low-temperature bath device, comprising a liquid nitrogen cooling system, an alcohol cooling system and a PID intelligent temperature control system. The device integrates the stations of the liquid nitrogen cooling system and the alcohol cooling system on a main body machine; the liquid nitrogen cooling system includes a self-pressurizing liquid nitrogen tank 12, the pressure reducing valve 11 of the self-pressurizing liquid nitrogen tank 12 is electrically connected to the solenoid valve port on the liquid nitrogen cooling system, and the solenoid valve port is electrically connected to the liquid nitrogen switch group 2 arranged on the outer wall of the main body machine 5; the liquid nitrogen switch group 2 supplies power to the whole system and the PID intelligent temperature control system; the self-pressurizing liquid nitrogen tank 12 is sequentially connected to the solenoid valve 15, the temperature regulating flow tube 14 through the pressure reducing valve 11, a pipeline and the ferrule type straight tube joint 16 and then communicated with the liquid nitrogen low-temperature freezing sample chamber 3. The ferrule type straight tube joint 16, the connected solenoid valve 15 and the temperature regulating flow tube 14 are all installed inside the main body machine. A first high-precision PT100 temperature sensor 4 is installed in the liquid nitrogen low-temperature freezing sample chamber 3, and the solenoid valve 15, the liquid nitrogen switch group 2, the first high-precision PT100 temperature sensor 3 are electrically connected to the PID intelligent temperature control system; the alcohol cooling system includes an alcohol low-temperature freezing sample chamber 7, in which a second high-precision PT100 temperature sensor 13 is installed, a stirrer 6 is installed on the upper part of the alcohol low-temperature freezing sample chamber 7, and a cascade compression refrigeration system 10 is installed on the lower part of the outer lower part of the main body machine, that is, the cascade compression refrigeration system 10 is used to adjust and control the temperature in the alcohol low-temperature freezing sample chamber 7; the cascade compression refrigeration system 10, the second high-precision PT100 temperature sensor 13, the stirrer 6 are all electrically connected to the PID intelligent temperature control system, and the control switch group 9 of the cascade compression refrigeration system 10 is installed on the outer wall of the main body machine; the liquid nitrogen low-temperature freezing sample chamber 3 and the alcohol low-temperature freezing sample chamber 7 are arranged in parallel on the upper part of the main body machine.

[0020] The above-mentioned liquid nitrogen cooling system, alcohol cooling system, PID intelligent temperature control system and cascade compression refrigeration system are all prior arts. The functions of these systems are briefly described below.

[0021] The liquid nitrogen cooling system is an efficient and precise temperature control solution, designed specifically for scientific experiments, material testing and sample preservation that require extremely low temperature environments. This system integrates advanced PID intelligent temperature control technology, and through the intelligent adjustment of the PID intelligent temperature control technology, precise management of liquid nitrogen use and stable control of temperature are achieved. Composition of the liquid nitrogen cooling system: PID intelligent temperature control system: As the core brain of the system, it adopts the PID (Proportional-Integral-Differential) control algorithm, is responsible for receiving data from the temperature acquisition system, and automatically adjusts the control quantity (here it is the liquid nitrogen flow rate) according to the deviation between the set value and the actual value to achieve closed-loop temperature control; Liquid nitrogen switch group: including manual or automatic control, used for power management of the entire system, starting and stopping liquid nitrogen supply precisely, safely and efficiently; Temperature acquisition system: Adopts high-precision PT100 temperature sensors directly installed in the sample chamber, monitors and feeds back temperature data to the PID intelligent temperature control system in real time to ensure the accuracy and timeliness of temperature control. The present utility model adds an electromagnetic valve and a temperature regulating flow tube to the liquid nitrogen refrigeration system, innovatively combines the quick response of the electromagnetic valve and the fine adjustment ability of the temperature regulating flow tube, precisely controls the supply amount of liquid nitrogen through the PID intelligent algorithm, realizes fine adjustment and stable maintenance of temperature. Its main working process: Open the pressure reducing valve of the liquid nitrogen tank, and the liquid nitrogen flows through the temperature regulating flow tube to the sample chamber. The first high-precision PT100 temperature sensor collects the temperature of the sample chamber in real time. When the temperature of the sample chamber reaches the set temperature, the signal of the first high-precision PT100 temperature sensor is sent to the PID controller, and the PID system controls the opening and closing of the electromagnetic valve 15 to achieve the purpose of constant temperature. Self-pressurizing liquid nitrogen tank: As the storage and supply source of liquid nitrogen, it has a self-pressurizing function, can stably and continuously supply liquid nitrogen with the required pressure to the system, and ensures the continuity and reliability of the experiment.

[0022] The alcohol cooling system mainly consists of a mixer, a PID intelligent temperature control system, a second high-precision PT100 temperature sensor, an alcohol low-temperature freezing sample chamber, a control switch group and a cascade compression refrigeration system. The power of the cascade compressor is intelligently adjusted through the PID intelligent temperature control system to reach the test temperature. The cascade compression refrigeration system is a system composed of two refrigeration circuits. Each circuit is an independent refrigeration system, including a compressor, an evaporator, a condenser, and a throttling mechanism, and the evaporator in one circuit also serves as the condenser for cooling the refrigerant in the other circuit at the same time.

[0023] During use, add a certain amount of alcohol solution to the alcohol low-temperature freezing sample chamber. Turn on the control switch group of the cascade compressor to start the alcohol solution cooling system. Rapidly cool the solution temperature through the PID intelligent temperature control system and the cascade compression refrigeration system, so as to achieve the purpose of cooling the sample. When the high-precision PT100 temperature sensor collects that the solution temperature reaches the test set temperature, the PID intelligent temperature control system will intelligently adjust the operating power of the cascade compressor according to the solution temperature, so that the solution temperature meets the experimental requirements and achieves the requirement of precise temperature control. The PID intelligent temperature control system displays and starts to record the heat preservation time. When the heat preservation time arrives, the test can begin.

[0024] The liquid nitrogen low-temperature freezing sample chamber 3 and the alcohol low-temperature freezing sample chamber 7 are made of heat-insulating materials to ensure that the temperature inside the sample chamber is stable and uniform at extremely low liquid nitrogen temperatures or low temperatures, providing an ideal low-temperature environment for the samples.

[0025] The dimensions of the main body machine are: 96cm × 59cm × 78cm, reducing the occupancy requirements of the test site, saving the test site space and manufacturing costs. The double-station cooling tank of the main body machine adopts a sample rack with a grid. One station has three layers and can place about 120 standard samples (10×10×55mm), which can improve the efficiency of sample cooling.

[0026] The working process of the present utility model:

[0027] Alcohol cooling system:

[0028] Add cooling medium: Add about 4L of alcohol with a concentration of more than 99.7% to the alcohol low-temperature freezing sample chamber 7.

[0029] (2) Sample placement: After placing the cleaned samples neatly on the sample grid in order, put them together into the alcohol low-temperature freezing sample chamber 7.

[0030] (3) Start the device: Turn on the control switch group 9, set the test temperature through the alcohol system temperature control screen 8, and the cascade compression refrigeration system 10 starts to work. Press the alcohol stirrer and the high-precision temperature acquisition system to check whether the alcohol fluidity in the alcohol low-temperature freezing sample chamber 7 is good.

[0031] (4) Sample heat preservation: When the test temperature displayed on the alcohol system temperature control screen 8 reaches the heat preservation time, the indicator light flashes and the sample heat preservation is completed.

[0032] (5) Start the test: Use the sample tongs to quickly clamp the sample from the alcohol low-temperature freezing sample chamber 7 to the impact device.

[0033] (6) Test end: After the test is over, turn off the control switch group 9 of the compressor and the power switch.

[0034] Liquid nitrogen cooling system:

[0035] (1) Add cooling medium: Add about 50 L of liquid nitrogen from the self-pressurizing liquid nitrogen tank 12 and open the valve of the liquid nitrogen tank.

[0036] (2) Place the specimen: After neatly arranging the cleaned specimens on the specimen grid in sequence, put them into the liquid nitrogen low-temperature freezing specimen chamber 3 together.

[0037] (3) Start the device: Open the liquid nitrogen switch group 2, set the test temperature through the liquid nitrogen system temperature display screen 1, and the liquid nitrogen refrigeration system, solenoid valve, and temperature regulating flow tube start to work.

[0038] (4) Insulate the specimen: When the test temperature displayed on the liquid nitrogen system temperature display screen 1 reaches the insulation time, the indicator light flashes and the specimen insulation is completed.

[0039] (5) Start the test: Use the specimen tongs to quickly clamp the specimen from the liquid nitrogen low-temperature freezing specimen chamber 3 to the impact device to complete the impact test.

[0040] (6) End of the test: After the test is completed, turn off the liquid nitrogen switch group 2 and the power switch.

Claims

1. A hybrid refrigeration double-station rapid cooling cryogenic bath device, comprising a liquid nitrogen cooling system, an alcohol cooling system and a PID intelligent temperature control system, characterized in that, The device integrates the workstations of the liquid nitrogen cooling system and the alcohol cooling system on a main body machine (5); the liquid nitrogen cooling system includes a self-pressurizing liquid nitrogen tank (12), the pressure reducing valve (11) of the self-pressurizing liquid nitrogen tank (12) is electrically connected to the solenoid valve port on the liquid nitrogen cooling system, and the solenoid valve port is electrically connected to the liquid nitrogen switch group (2) arranged on the outer wall of the main body machine (5); the self-pressurizing liquid nitrogen tank (12) is communicated with a liquid nitrogen low-temperature freezing sample chamber (3) through a pressure reducing valve (11) and a solenoid valve (15), a temperature regulating flow tube (14) and a pipeline installed in sequence, a first high-precision PT100 temperature sensor (4) is installed in the liquid nitrogen low-temperature freezing sample chamber (3), and the solenoid valve (15), the liquid nitrogen switch group (2), the first high-precision PT100 temperature sensor (4) are electrically connected to a PID intelligent temperature control system; the alcohol cooling system includes an alcohol low-temperature freezing sample chamber (7), a second high-precision PT100 temperature sensor (13) is installed therein, a stirrer (6) is installed on the upper part of the alcohol low-temperature freezing sample chamber (7), and a cascade compression refrigeration system (10) is installed on the lower outer part, i.e., the lower part of the main body machine, and the cascade compression refrigeration system (10) is used to adjust and control the temperature in the alcohol low-temperature freezing sample chamber (7); the cascade compression refrigeration system (10), the second high-precision PT100 temperature sensor (13), and the stirrer (6) are all electrically connected to the PID intelligent temperature control system, and the control switch group (9) of the cascade compression refrigeration system (10) is installed on the outer wall of the main body machine; the liquid nitrogen low-temperature freezing sample chamber (3) and the alcohol low-temperature freezing sample chamber (7) are arranged in parallel on the upper part of the main body machine.

2. The hybrid refrigeration double-station rapid cooling low-temperature bath device according to claim 1, characterized in that: The liquid nitrogen low-temperature freezing sample chamber (3) and the alcohol low-temperature freezing sample chamber (7) are made of heat-insulating materials.

3. The hybrid refrigeration double-station rapid cooling low-temperature bath device according to claim 1, wherein: The size of the main body machine is: 96 cm × 59 cm × 78 cm.

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