1. Design basis and guiding ideology

The liquid thermal shock test chamber is an extension of our company's standardized products for thermal shock series. The liquid thermal shock test chamber uses a stirred convective liquid medium instead of a circulating air medium for heat transfer, which can meet the rigorous testing requirements. The system structure can be divided into high-temperature liquid tanks (preheating zone). The two parts of the low-temperature liquid tank (pre cooling zone) simulate the instantaneous environmental changes between high and low temperatures by controlling the mechanical transmission components to alternately place the test samples into the high and low-temperature liquid tanks.

Working principle of liquid thermal shock test chamber: The automatic mechanical temperature zone conversion system uses a high-temperature liquid tank (preheating zone) and a low-temperature liquid tank (pre cooling zone) to pre raise and lower the temperature and store energy. According to the needs of the test action, the mechanical mobile sample box (test sample placement area) is controlled to quickly move to the low-temperature liquid tank or high-temperature liquid tank to achieve rapid thermal shock testing. Balanced Temperature Control System (BTC), a temperature controller that combines the cooling output of the refrigeration system or the heating output of the heating system, and controls the heating system to generate corresponding heat output through PID algorithm or intelligently adjusts the cooling capacity to control the cooling output of the refrigeration system. Cold and heat are transmitted through specially designed liquid fluids, evenly distributed in the liquid test area, to continuously compensate for the loss of cold and heat that maintains the set temperature in the liquid test area, thereby achieving rapid and constant temperature control.

2. Standards

GB/T10589-2008 Technical Conditions for Low Temperature Test Chamber

US military standard MIL-STD-883E

GB/T 10590-2006 Technical Conditions for High, Low Temperature, and Low Pressure Test Chambers

GB/T11158-2008 Technical Conditions for High Temperature Test Chamber

GB T5170.1-2008 General Principles for Inspection Methods of Environmental Testing Equipment for Electrical and Electronic Industries

GB/T5170.2 Basic parameter calibration method

3. High performance&low energy consumption

Professional liquid circulation mixing design: using a built-in liquid mixing motor to ensure a uniform temperature field of the liquid inside the tank and small temperature deviation;

Cooling: Equipped with a built-in high-efficiency evaporator, it has strong frost resistance, small heat transfer temperature difference, and fast cooling rate; The inner wall auxiliary evaporator and self balancing heating system increase radiation heat transfer under vacuum conditions, resulting in high temperature uniformity inside the box.

Low power consumption:

A. The test chamber adopts VRF (Variable Refrigerant Flow) technology: the controller drives the electronic expansion valve through PID output to adjust the cooling capacity, achieving constant temperature and humidity. Unlike the traditional BTHC control method (i.e. balanced temperature and humidity control: continuous cooling by compressor, stable temperature and humidity control by heating and humidification), VRF technology can achieve low temperature and room temperature stability without the need to turn on the heater, and can reduce energy consumption by more than 40% without running at the same time.

B. The pressure bearing box is lined with a special air insulation structure, which greatly reduces the cold and hot loads during the temperature rise and fall process, reduces installed power, and lowers operating costs.

4. High reliability

Refrigeration:

A. Using French imported brand compressors, with complete safety protection functions and high reliability;

B. The main refrigeration and accessories are made of internationally renowned brands;

C. Adopting precise calculation of capillary throttling control for cooling, adjusting the cooling capacity within the range of 0-100% through pulse switch signals.

D. An efficient centrifugal oil separator with a separation efficiency of over 99% ensures the service life of the compressor.

E. The dual regulation and protection of compressor suction pressure and temperature ensure the safety of the compressor under various working conditions.

Control: 7-inch touch screen, equipped with a French Schneider based electrical actuator, fully automatic system control, high operational reliability.

The high and low temperature liquid tanks adopt forced stirring convection method.

Adopting a fully automatic up, down, left, and right displacement mechanism to move the sample basket to the preheating and pre cooling tanks, using a back and forth impact method.

Fluorine oil uses a single identical liquid in high and low temperature tanks to reduce the cost of frequent liquid changes.

Adopting the original LCD integrated with both Chinese and English color LCD touch screen main brain controller

This equipment can be cooled by water or air cooling to meet the needs of the site

The movement time of this thermal shock mechanism is within 10 seconds.