For decades, copper tubes have been used for heat exchange tubes in air conditioners, refrigerators, and other refrigeration products. However, under the global demand for copper resources and international copper prices, the search for ideal alternative materials and the saving of copper resources have become a hot spot in the industry. Industry has tried water energy conservation R&D
In addition to petroleum, copper has become the second major strategic resource that affects the country’s economic security. Chen Lianying, deputy director of the Copper Industry Department of the China Nonferrous Metals Processing Industry Association, said that in recent years, the price of international electrolytic copper has risen from 20,000 yuan per ton to 7 to 80,000 yuan. Correspondingly, the proportion of copper pipes in the cost of air-conditioning has been With an increase to about 25%, the operating costs of refrigeration product companies such as air-conditioners have risen sharply, and there is an urgent need for ideal alternative materials. How to develop new materials for refrigeration and air conditioning, improve quality and technological competitiveness, and expand the pipe manufacturers' own living space has become a practical problem facing pipe manufacturers.
It is understood that in the past decade, industry researchers have been trying to find alternative materials and reduce costs. Major air-conditioning plants have carried out trial production of pure aluminum air conditioners and research and development of copper-aluminum composite technology. However, due to the large difference in heat transfer performance between aluminum and copper, all aluminum air conditioners fail to meet the national energy efficiency standards, and the promotion has been greatly hindered. In contrast, copper and aluminum composite technologies used in the past have used copper tubes and aluminum tubes in combination. By means of re-stretching and the like, it is difficult to achieve a good and firm interface between copper and aluminum, which seriously affects the heat conduction function of the product.
Under this premise, if we can develop new copper-aluminum composite materials and overcome the deficiencies of copper-aluminum composite technology in the past, we will open up a new world for enterprise development. Xingrong Hi-Tech decided to take the commanding heights of this industry. As early as 2005, the company set up a composite test group and began to explore the use of composite materials instead of pure copper. Another way to break through technical difficulties
According to the suggestion that aluminum alloy air conditioning and copper clad aluminum wire had appeared in the market, Xingrong Hi-tech Co., Ltd. determined that aluminum is a better alternative to copper. The proportion of aluminum is 1/3 of that of copper. The price of aluminum ingots on the market is also 1/3 of that of electrolytic copper, and China's aluminum resources are abundant.
How can a "perfect" composite of aluminum and copper be made? Xingrong Hi-Tech tried unsuccessful methods such as composite re-stretching and cladding welding of copper tubes and aluminum tubes. After that, it conducted several months of search and verification of patents, data, intelligence, and related developments at home and abroad. In addition, a large number of experiments on rolling, extrusion and other processes were carried out. Finally, a new production method was invented. Xingrong decided to walk a road that no one had before and invented an unprecedented production method.
Xingrong Hi-Tech Co., Ltd. uses a rolling mill to carry out composite rolling of copper-aluminum composite billets. During the rolling, it generates heat of deformation. The large deformations with the pressure and deformation rate reaching 90% produce a large amount of new metals that contain only copper and aluminum without any oxides. Through the deformation heat generated during rolling and the rolling pressure and the surface of the fresh metal formed by the large deformation, copper and aluminum are mutually diffused to form a metallurgical bonding layer at the interface atoms, thereby obtaining an integrated copper-aluminum composite pipe.
At the end of 2005, Xingrong Hi-Tech Co., Ltd. produced a copper-aluminum composite pipe that was metallurgically bonded to the front copper and aluminum at home and abroad. During the period, they applied for 5 Chinese invention patents and 12 PCT patents.
Even if the product is still in trial use, it has been identified by the Chinese Academy of Engineering, the China Non-Ferrous Metals Processing Industry Association, the Beijing Non-ferrous Metal Research Institute, and other 9 academicians and experts as "one of the world's first new technologies." extensive attention.
This technology is of great significance. Saving energy and saving materials will not reduce energy efficiency. Chen Lianying analyzed that the traditional air conditioning refrigerant carrier is a copper tube and the heat sink is aluminum. The instantaneous heat absorption capacity of copper is better than that of aluminum, but its heat dissipation capacity is worse than that of aluminum. The copper-aluminum composite pipe concentrates the advantages of copper and aluminum. The copper pipe is used as the inner pipe of the product, and the aluminum pipe is used as the outer pipe. The metallurgical bonding between the pipes is achieved through special processes. After trials by more than a dozen air-conditioning companies such as Gree, Midea, Galanz, and Shinco, compared with traditional air conditioners, the air-conditioning energy efficiency ratio of copper-aluminum composite pipes has increased by more than 5%.
In addition, in addition to air-conditioning, refrigerators and other refrigeration industries, the automotive, equipment manufacturing, municipal construction, especially urban water supply and other areas, the demand for copper pipe is also very large. Where the use of pure copper tubes previously had the possibility of replacing them with copper-aluminum composite tubes, the market prospects of the products are very promising.