The air conditioner is mainly composed of a compressor, a radiator, and an automatic control system. The copper pipe in the radiator is called the "blood vessel" of the air conditioner in the industry. The quality of the "blood vessel" will directly determine the quality of the air conditioner. Let's combine the production practice below , talk about the problems that often occur in the use of air-conditioning refrigeration copper pipes.
Copper tubes are an important raw material for refrigeration devices, and they have two main uses:
① Make a heat exchanger. Such as commonly used evaporators and condensers, commonly known as "two devices".
② Make connecting pipe fittings. Regardless of the purpose, it is a channel for refrigerant, and its role is very important.
On the one hand, wholesale copper tube suppliers are required to provide high-quality copper tubes, and on the other hand, air-conditioning and refrigeration companies are required to properly use copper tubes.
Coil pipe: currently mainly used for two device supervisors, connecting pipes, pipe fittings, etc. Features: Easy to transport, users are not limited by length during use.
Mosquito coils: mainly used in the maintenance market. Features: Easy to use.
Straight pipe: like air conditioning copper pipe fittings, mainly used for central air-conditioning and connecting pipes. Features: Inconvenient transportation, length limitation in use.
Copper pipe leakage is a fatal flaw of the air conditioner. Once it leaks, all the refrigerant of the air conditioner will overflow, and the air conditioner will fail due to the lack of heat transfer medium. The reasons for the leakage of copper pipes are more complicated, and the reasons for frequent leakage are explained below.
1. Manufacturing reasons
① Eddy current flaw detection missed detection. GB stipulates that 100% eddy current flaw detection must be carried out on copper pipes, and stipulates the diameter of artificial defects (holes) on the sample tube used for checking flaw detectors, so as to ensure the sensitivity of eddy current flaw detection and prevent excessive defects from being missed.
This requirement can be fully guaranteed in regular large-scale copper pipe factories, because the flaw detection is online detection. This online eddy current flaw detection ensures that all lengths of the pipe have been tested by eddy current, which is 100% flaw detection.
Some copper pipe factories are not like this, or do not pass eddy current flaw detection, or use low-standard eddy current flaw detectors for random inspection. In this way, there are defects in the copper pipe that exceed the standard, which are missed or not detected, causing the air conditioner to leak when the user uses it.
②Eddy current testing detects defects, but the surface of the copper tube is not marked or the marking is inaccurate and unclear. In the production process of copper tubes, the defects detected by eddy current flaw detection are required to be covered with ink on the defects exceeding the standard, so that the user can remove the defective copper tubes during use.
However, due to the insufficient adhesion of the ink selected by the manufacturer during the production process, improper adjustment of the inkjet spray gun, incomplete drying, and ink components that encounter high temperature fading, etc., the user cannot detect the eddy current flaw detection during use. If the defects are picked out, once the defective copper pipes are used on the air conditioner, it will inevitably cause leakage.
2. Reasons for users to use
① Misuse of defective tubes detected by eddy current testing. Air-conditioning and refrigeration enterprises should explain clearly to operators, especially new workers, so as to prevent such damaged pipes from being installed on air-conditioning and refrigeration equipment.
②Processing problems. In the process of forming the two devices, the air-conditioning supervisor has to go through bending, expanding, flaring, welding and other links. In the process of bending the pipe, due to the local stress on the bent part, it will cause local overstretching, resulting in cracks, dark cracks and other problems. Once the refrigerant is filled, refrigerant leakage often occurs here.