Function of leakage detection equipment for automobile air conditioner
Leak detection equipment is used to check whether the refrigerant in the air conditioning system leaks.
Refrigerant is a substance that is easy to evaporate. Under normal conditions, its boiling point is - 29.8 ℃.
Therefore, the whole refrigeration system is required to be well sealed, otherwise the refrigerant will leak and affect the refrigeration efficiency.
Therefore, it is necessary to regularly check the refrigeration system for leakage. After disassembling or overhauling the pipeline of automobile air conditioning and refrigeration system and replacing parts, leakage inspection shall be carried out at the overhaul and disassembly parts.
The leak detection equipment is used to check whether the refrigerant in the air conditioning system leaks. Refrigerant is a very easy to evaporate substance, under normal conditions, its boiling point is -29.8℃. Therefore, the entire refrigeration system is required to be well sealed, otherwise the refrigerant will leak, affecting the refrigeration efficiency. Therefore, it is necessary to check the refrigeration system for leakage. When disassembling or repairing the pipes of automobile air conditioning refrigeration system and replacing parts, leakage inspection should be carried out at the repair and disassembly parts. Automotive air conditioning commonly used leak detection equipment: leak detection equipment including halogen leak lamp, dye leak detector, fluorescent leak detector, electronic leak detector, helium mass spectrometry leak detector, ultrasonic leak detector and so on. Halogen leak detection lamp can only be used for R12, R22 and other halogen refrigerant leak detection
Common leak detection equipment for automobile air conditioner include
Leak detection equipment includes halogen leak detector, dye leak detector, fluorescent leak detector, electronic leak detector, helium mass spectrometer leak detector, ultrasonic leak detector, etc.
The halogen leak detection lamp can only be used for leak detection of halogen refrigerants such as R12 and R22, and has no effect on new refrigerants such as R134a without chloride ions.
The electronic leak detector also has applicability to common refrigerants, which should be paid attention to during use.
Halogen lamp leak detection method
When halogen lamp is used for inspection, its use method should be strictly observed. After the flame is adjusted correctly, let the suction pipe mouth close to the detected part, observe the change of flame color, then we can judge the leakage situation. The right table shows the corresponding situation of leakage size and flame color.
Flame condition R12 monthly leakage, G
No change is less than 4
Micro green 24
Light green 32
Dark green, 42
Green, purple, 114
Greenish purple with purple 163
Strong purple green purple 500
The instrument is made of the basic principle that halide gas has inhibitory effect on negative corona discharge. When in use, just extend the probe to the part that may leak. If there is leakage, the alarm bell or alarm light will show the corresponding signal according to the amount of leakage.
Positive pressure leak detection method
After the system is repaired and before filling with fluorine, a small amount of gaseous fluorine is filled first, and then nitrogen is filled to pressurize the system, so that the pressure reaches 1.4~ 1.5mpa and the pressure is maintained for 12h. When the gauge pressure drops more than 0.005MPa, it indicates that the system is leaking. First, rough inspection with soapy water, and then fine inspection with halogen lamp to identify the specific leakage site.
Negative pressure leak detection method
Vacuum the system, keep it for a certain time, and observe the pressure change of the vacuum gauge. If the vacuum degree drops, it indicates that the system is leaking.
The latter two methods can only detect whether the system is leaking. The first five methods can detect the specific location of the leak. The first three methods are intuitive and convenient, but some parts are inconvenient to check and trace leakage is not easy to detect, so they are only used as rough inspection. The halogen leak detector is very sensitive and can detect when the cooling system leaks more than 0.5g per year. But because of the leakage of refrigerant around the system space can also be measured, will misjudge the leakage site and the instrument is high cost, expensive, generally not used. Although the halogen lamp inspection is slightly troublesome, it is the most commonly used because of its simple structure, low price and high detection accuracy.
Post time: Dec-01-2021