In industrial production, there are too many applicatio […]
In industrial production, there are too many applications of refrigerators. Some equipment has been in disrepair for a long time, and the maintenance is not in place. The phenomenon of poor cooling effect often occurs. The following Kedley chiller editor will show friends in the industry to understand this phenomenon and find Ways and methods of processing.
A real application of a refrigerator is used to illustrate this problem. In the polymerization reaction, the reaction conditions of high polymer polypropylene are extremely harsh. It is necessary to control the loop reactor to about 18 degrees, and the freezer to Air-Cooled Condenser discharge water at 2 degrees. The normal operation takes away the reaction heat. The poor refrigeration effect of the freezer will cause serious accidents, shutdown processing, and delays in production.
Let's talk about several reasons for the poor cooling effect of the refrigerator.
Failure of expansion valve
As an important part of the refrigeration system of the refrigerator, the expansion valve bears too much. It achieves the pressure drop from the condensing pressure to the evaporating pressure, while also taking into account the control of the refrigerant flow rate, which contributes a lot to the operation of the refrigeration system.
The low inlet pressure of the refrigerating unit leads to a chain shutdown. If the amount of refrigerant is normal, first suspect that the expansion valve is faulty. Blockage of the expansion valve and icing will cause the refrigerant to not enter the evaporator, resulting in poor cooling effect. If no obvious impurities are found in the drier of the chiller, eliminate the problem of blockage of the expansion valve.
Improper setting of the overheating degree of the expansion valve can also cause abnormal operation. You can judge whether this is the cause by checking the valve opening.
The evaporator is malfunctioning
The evaporator is a part that exchanges heat between the chilled water and the refrigerant. If the shell leaks, the circulation volume will be reduced and the cooling effect will be worse. By testing the water pressure on the tube side of the heat exchanger, it can be judged whether this is the cause.
Operation failure of oil-water separator
The oil-water separator is a device that separates the oil and the refrigerant in the chiller system. The working condition is relatively bad, and it should be checked or replaced periodically. By observing the oil separator window, you can observe whether the refrigerant is oily, and this fault can be judged.
Compressor internal failure
The compressor is the core of the entire refrigeration system, and it is responsible for the compression work. The internal structure also determines its efficiency, such as screw type, turbine type, piston type, etc., taking the screw as an example, the slide valve can adjust the working volume to achieve the compressor load. Variety.
Failure of the spool valve will cause the compressor to work abnormally, resulting in poor cooling effect.
The above four reasons can be used to periodically maintain the refrigerator to reduce the frequency of failures and extend the life of the equipment. There are many factors that cause the refrigerator to not refrigerate. This can be found and resolved through observation, analysis, replacement, and maintenance. Class failure to ensure the safe operation of the freezer.