The selection technique of refrigerating oil display cabinet
1. Brand selection. At present, there are five main types of frozen oil produced in China, and its number is determined by its kinematic viscosity, which has a high viscosity and a high mark. Different type of frozen oil won't mix, but can substitute, the substitution principle is: high quality refrigeration oil can replace the low grade frozen oil, and low grade frozen oil is not a substitute for high grade freezing oil. The use of R12 for refrigerant compressor is suitable for HD-18 freezing oil; The use of R22 for refrigerant compressor is suitable for the HD-25 oil.
2. Quality judgment. The quality of the frozen oil can be preliminarily judged. When the frozen oil contains impurities or moisture, its transparency decreases; When the frozen oil goes bad, its color gets darker. Therefore, can drop a drop of frozen oil on the white clean blotting paper, if the oil trace color is shallow and even, the frozen oil quality can be; If the oil trace is a group of concentric circles, the frozen oil contains impurities; If the oil stain is brown and spotted, the frozen oil is spoiled and can no longer be used. The high quality frozen oil should be colorless and transparent, and it will become light yellow after a period of time. As the use time is prolonged, the color of the oil will gradually deepen and the opacity will deteriorate. If frozen oil turns orange or reddish brown, replace it.