What affects the homogeneity of the cryogenic chamber

High and low temperature test box temperature difference between the various points of the temperature? What influences the homogeneity of the high and low temperature chambers? When people use the test box, sometimes this problem occurs. How should we understand and solve some problems? The following Yashilin equipment service department has summed up many years of maintenance experience and lists it for you:
    One is that the volume of the test sample is too large. If the volume of the test sample is too large, the wind circulation in the test box will be affected, resulting in an excessive deviation of the temperature uniformity. According to the standards, the test sample volume should not exceed 1/3 of the laboratory space.
    Second: The test sample has a load. If the test sample has a load, it is necessary to inform the manufacturer of the load in advance. Otherwise it will have a great influence on the follow-up test.
Third, the placement of the test sample. If the test sample is placed incorrectly and air convection is obstructed, large temperature deviations will also result. Must not be placed at the outlet.
    Fourth, the test chamber is poorly sealed. For example, the door leaks, which is also one of the important factors affecting the uniformity of the test chamber temperature.
    Fifth: box structure. Due to the unreasonable design of high and low temperature tanks by manufacturers, the temperature in the middle of the work is affected to a great extent. The best structure should be easy to reach the temperature of the left and right: heating and cooling should be in the back of the box, send air under the return air, forced convection.
    Temperature uniformity is the most basic and most important factor in the detection of high and low temperature test chambers. Therefore, if the customer chooses this is an important assessment point, the national standard specifies that the temperature uniformity is ±2°C.