How to blow pollution after installation of cold storage refrigeration system

How to blow pollution after installation of cold storage refrigeration system

The reason for blowing dirt after the refrigeration system is installed is that during the installation or maintenance of the refrigeration system, there will inevitably be welding slag, rust, oxide scale and other impurities in the refrigeration system. If it is not cleaned up, the refrigeration device is running Impurities will damage the valve core; impurities passing through the cylinder will make the mirror surface of the cylinder "fuzzy"; impurities passing through the expansion valve, capillary tube and filter, etc., will cause blockage failure. The remaining dirt in the system reacts chemically with refrigerant and lubricating oil, which can also cause corrosion. Therefore, after the completion of system maintenance for small and medium-sized refrigeration systems, in order to prevent foreign matter from remaining inside the system, blow dirt operations should be performed

How to blow dirt after the cold storage refrigeration system is installed?

　　The method of blowing dirt after the refrigeration system is installed is to blow dirt on the refrigeration system in stages. The procedure is to blow the dirt on the high pressure part of the refrigeration system first, and then blow the dirt on the low pressure part of the refrigeration system. The outlet of the refrigeration system should be selected at the lowest point of each section, and the sewage outlet of each section should be fastened with wire in advance. The specific operation steps are as follows.

The first step is to connect the spare port of the compressor high pressure shut-off valve to the nitrogen cylinder with a pressure-resistant pipe, remove the filter drier from the system, open the nitrogen cylinder valve, and blow the high pressure of the system with nitrogen with a pressure of 0.6MPa. When the pressure reaches 0.6MPa gauge pressure, stop the inflation. Then the cork is quickly removed, and the dirt in the system is discharged by the high-speed airflow. And use a piece of white paper on the air outlet to check for dirt. It depends on the degree of cleanliness. If the white paper is cleaner, it means that the dirt washed out with the gas is gone, and you can stop blowing dirt.

The second step is to connect the spare port of the compressor low-pressure shut-off valve and the nitrogen bottle with a pressure-resistant pipe, and still use the dry filter interface as the detection port, open the nitrogen bottle valve, and blow the low pressure of the system with nitrogen with a pressure of 0.6MPa. Section, still use white paper on the air outlet to check for dirt. After confirming that there is no dirt, the blowing process ends. The small cold storage refrigeration system should perform pressure leak testing after the system is blown. The method is to install a pressure gauge with a range of 0~2.5MPa on the spare port of the compressor high pressure stop valve; install a pressure gauge with a range of -0.1 to 1.6MPa on the multi-purpose port of the compressor low pressure stop valve.