News
Refrigerant Tank and Inspection
- November 4, 2022
- Fonsum
Classification of refrigerants
Refrigerant is the medium material used to complete energy conversion in various heat engines. Refrigerants widely used in compression refrigerants are ammonia, freon and hydrocarbons.
According to chemical composition, refrigerants can be divided into five categories: inorganic compound refrigerants, Freon, saturated hydrocarbon refrigerants, unsaturated hydrocarbon refrigerants and azeotrope refrigerants.
Depending on the condensing pressure, refrigerants can be divided into three categories: high temperature (low pressure) refrigerants, medium temperature (medium pressure) refrigerants, and low temperature (high pressure) refrigerants.
Commonly used Freon refrigerants are R22, R502 and R134a, and other types of refrigerants have now been disabled or banned.
Refrigerant 22 (CHF2CL, R22) is one of the most widely used Freon refrigerants, mainly used in household air conditioners and low-temperature refrigerators.
Refrigerant 502 (R502 is an azeotropic solution mixed with R12 and R22 in percentages of 51.2% and 48.8%.
Refrigerant 134a (C2H2F4, R134a) is a relatively new type of refrigerant with an evaporation temperature of -26.5°C.
Canning and storage of refrigerants
Commonly used refrigerants are stored and transported in tanks. Tank containers are containers used to transport liquid goods such as sprinkles, oils, liquid foods, and chemicals. It is mainly composed of a liquid tank and a frame. The liquid tank is elliptical or approximately spherical and adopts a double-layer structure. The inner wall is made of stainless steel or other rigid materials but needs to be coated with a layer of epoxy resin to prevent the corrosion of liquid cargo. The outer wall is made of thermal insulation material. Generally, the top of the tank has a circular loading port, and the bottom of the tank has a discharge valve. The frame is made of high-strength steel, and the liquid tank is placed in the middle of the frame. The handling, loading, unloading, and storage of tank containers all require a special place and special fire safety equipment.
The external frame size of the tank container is exactly equal to the size of the international standard 20 containers (length 20 feet, width: 8 feet, height: 8 feet 6 inches), which can be used for road, rail, and water transportation. It can carry fluid cargo up to 14,300 to 31,000 liters (or more).
Inspection process of refrigerants
1. The regular inspection of tank containers is divided into annual inspection and comprehensive inspection. The annual inspection is carried out once a year, and the safety condition level is 1-2. The comprehensive inspection is carried out every 5 years, the safety condition level is 3, and the comprehensive inspection is carried out every 2.5 years.
2. For tanks carrying flammable or suffocating media, the media in the tank must be discharged and cleaned up, and residual liquid (gas) treatment, neutralization disinfection, cleaning, steam purging, ventilation, and replacement should be carried out for sampling analysis and analysis results. The relevant standards must be met. The oxygen content in the gas reaches 18% to 23% (volume ratio) to be qualified. Into the tank for inspection, the surface must be thoroughly cleaned and the metallic luster should be exposed. The power consumption for inspection lighting should not exceed 24V.
3. The annual inspection items for tank containers include tank data review, tank appearance inspection, tank ancillary facility connection inspection, insulation layer inspection, accessory inspection, safety accessory inspection, assembly inspection, pressure resistance inspection (if necessary), air tightness test, etc.
4. The comprehensive inspection items include the entire contents of the annual inspection of the tank body, structural inspection and geometric dimension inspection, emergency shut-off valve pressure test, wall thickness determination, surface defect and buried defect inspection, tank outer surface paint inspection, strength check, and so on.