High and low temperature cycle integrated machineIt is a commonly used temperature control equipment in laboratories and industrial production, which can achieve precise high and low temperature switching and constant temperature control. It is widely used in temperature regulation of reaction vessels, extraction devices, condensation equipment, etc. Below is a simple language to explain its working principle, which is easy to understand at a glance.
1、 Core work logic
High and low temperature cycle integrated machineThe core of the system is to provide a stable and controllable temperature environment for the target equipment or medium through the collaborative operation of refrigeration and heating systems, combined with circulation pipelines. The overall system can be regarded as a combination of "temperature generation module+circulation conveying module+intelligent control module", and the three are linked to achieve precise temperature control.
2、 Working principle of each module
1. Heating module
The heating function mainly relies on electric heating tubes to achieve:
When the control system detects that the temperature of the circulating medium (commonly used heat transfer oil, ethylene glycol aqueous solution, etc.) is lower than the set value and needs to be raised, the electric heating tube will be activated.
After the electric heating tube is powered on, it generates heat and directly transfers it to the circulating medium, gradually increasing its temperature. When it reaches the set temperature, the heating tube will automatically stop working and maintain the constant temperature of the medium.
2. Refrigeration module
The principle of the refrigeration module is similar to that of a household air conditioner, using a compression refrigeration cycle. The core components include a compressor, condenser, expansion valve, and evaporator
Compression stage: The compressor compresses low-temperature and low-pressure refrigerant gas into high-temperature and high-pressure gas, increasing the energy level of the refrigerant.
Condensation stage: High temperature and high pressure refrigerant gas enters the condenser, releases heat through air or water cooling, and becomes low-temperature and high-pressure liquid refrigerant after cooling.
Throttle stage: After passing through the expansion valve, the pressure and temperature of the liquid refrigerant sharply decrease, becoming a low-temperature and low-pressure gas-liquid mixture.
Evaporation stage: Low temperature and low-pressure refrigerant enters the evaporator, exchanges heat with the medium in the circulation pipeline, absorbs heat from the medium, vaporizes into gas, and then re enters the compressor to complete the refrigeration cycle.
When the temperature of the medium is higher than the set value, the refrigeration module starts and takes away the heat of the medium through the above cycle to achieve cooling.
3. Circular conveying module
The core of this module is the circulation pump, which is equipped with sealed pipelines and liquid storage tanks:
The liquid storage tank is used to store the circulating medium, and the circulating pump provides power for the flow of the medium, pushing it to continuously circulate between the heating/cooling area inside the integrated machine and the controlled equipment outside (such as the reactor jacket).
After temperature regulation is completed in the integrated machine, the medium is transported to the controlled equipment for heat exchange, and then flows back to the integrated machine for re temperature control, forming a closed-loop loop to ensure that the temperature of the controlled equipment remains stable within the set range.
4. Intelligent control module
The control module is equivalent to the "brain" of the device, consisting of temperature control sensors, PLC controllers, and touch display screens:
The temperature control sensor monitors the temperature of the circulating medium and controlled equipment in real time, and feeds back the data to the PLC controller.
The controller compares monitoring data with the set temperature, automatically determines whether to start the heating or cooling module, and adjusts parameters such as circulation pump speed, heating power, and cooling frequency to achieve precise temperature control.
The display screen is used by operators to set temperature, view operating status and historical data, and some devices also support fault alarm and automatic protection functions.
3、 The key to switching between high and low temperatures
The core of achieving rapid temperature change in the integrated high and low temperature cycle machine is the seamless switching between the refrigeration and heating systems, and is equipped with waste heat recovery or anti frosting devices:
When it is necessary to switch from low temperature to high temperature, the refrigeration module stops working, the heating module starts, and the circulation pump keeps running to quickly increase the temperature of the medium; Otherwise, turn off heating and turn on cooling.
Some high-end devices will undergo residual heat or cooling buffering treatment before switching to avoid damage to the equipment and controlled samples caused by sudden temperature changes.