How are the copper tubes and aluminum tubes welded in the air conditioner?
New ideas stem from extensive experimentation and analysisThe research group used welding method is usually used in resistance welding, they began to try to increase the pressure parameters of the experiment, some pipeline welded together can be torn down, and some not tear down, they found, through analysis, that can tear, formation of eutectic, and tear down it found no eutectic.
Thin wall welding is known as the world's problems, there are objective factors. The melting point of copper is 1083 degrees Celsius, the melting point of aluminum is 660 degrees Celsius, which is more than 400 degrees Celsius melting point, is the result of the formation of aluminum, copper may be weak. It is more difficult, but also will be natural aluminum to form an oxide film on the surface, the refrigeration pipeline cleanliness requirements, clearing method of additive with this film is not clear, it is difficult to use physical methods, the oxide film layer and the melting point of 2000 degrees Celsius, the three different melting point, resulting in welding weld welding is not very easy to form even. In the past, using some special welding methods, such as explosive welding, diffusion welding, welding, friction welding method, by applying the auxiliary welding, welding can also be achieved, but these methods can only be completed or above 1 mm copper aluminum tube welding, or as a result of High cost and complex process, not suitable for industrial production. Some countries try to use copper and aluminum eutectic structure of weld, welding for thin walled, conducted extensive research, but did not realize the industrial application of refrigeration and air conditioning pipeline. The wall is very thin, only the invention of new welding method of welding production forming thin-walled copper aluminum pipe industrialization in order to realize, instead of copper aluminum in the air conditioning and refrigeration pipeline on the target."First we follow the copper eutectic structure of weld experiments, results show that the tube wall is too thin, the eutectic structure is very fragile, therefore, the weld quality is very poor, or even hand tear tear down. So, we started to look for new ideas." Zhao Yue recalled.
Traditionally, refrigeration air conditioning products are used in copper. But copper is always a global shortage of resources, copper prices soaring, has affected the development of air-conditioning industry. But the aluminum resources in China are abundant, the aluminum industry is relatively developed. Therefore, the air conditioning refrigeration pipeline into aluminum and copper represent the general trend.With aluminum and copper, is the key technology of Cu Al pipe butt welding problems. Therefore, the welding industry has a good reputation in the domestic city of Qingdao Hai Qing machinery factory joint Ocean University of China, formed a research team, take the initiative to assume this technology research tasks.
Ocean University of China materials science and Engineering Research Institute senior engineer Zhao Yue said "we used 10 tons of copper, the countless times, only to find the welding creative methods contrary to the authority of the world is the real solution, this idea has created this new type air conditioning copper aluminum connecting pipe products"Zhao Yue said, known as the world problems, suitable for industrialized production technology of thin-wall copper aluminum welding, is the key technology of air conditioner connecting pipe of aluminum and copper. It is the world's problem is not exaggeration, many developed countries have studied for many years, the industry can only achieve a wall thickness of 1 mm above the welding of copper aluminum pipe but, than the thin copper aluminum pipe welding technology has been no breakthrough. "But we have to solve is, can be used for thin wall copper aluminum pipe butt welding problem of air conditioner production"
