Early in the year 1946 after the end of the Second World War, the United States formulated a "copper-based copper" technology policy in response to the shortage of copper resources, and stipulated that all relevant industries must be implemented. Since then. American wire and cable companies began to develop aluminum core wire and cable.
The birthplace of American aluminum core wire and cable
For many years, many wire and cable companies in the United States have accumulated rich experience in the improvement of manufacturing processes for aluminum and aluminum alloy conductors. Although research was conducted long ago, it was not until the 1960s that there were major discoveries in aluminum core wire and cable technology. A very important finding is that aluminum conductor wire and cable can be used for communication lines. The United Kingdom has also set up an aluminum-core telephone line in Antarctica to conduct low-temperature environmental tests. Later, with the development of composite metallurgy technology, some research and development laboratories of metallurgical companies have done a lot of research, and finally succeeded in developing aluminum alloys for electricians. In further studies, it has been found that aluminum alloys have some very good properties, such as greater strength, higher ductility, better heat resistance, and the like. Later, these aluminum alloy composites were included in the 8000 series aluminum alloy catalogue by Alcoa.
In the early 1960s, the use of aluminum conductors in building wires surged in the United States and Canada, and even aluminum conductors were used in small-size (AWG 10 and 12) building wires. Due to the low cost and wide availability of aluminum, aluminum-conductor building wires made of common grade aluminum grade AA-1350 are rapidly becoming popular, and many aluminum core wires are installed in many buildings in North America. Southwire began researching and developing new aluminum alloy building wires in 1968. It has made headway and began to promote applications in the United States and Canada. However, at the end of the 1960s, the early installation of aluminum core electrical lines continued to fail, and the power sector and residents made a lot of complaints.
Produce 8000 series aluminum alloys in response to product complaints
In order to solve these problems, in 1970, wire and cable companies and companies in other industries, such as electrical product laboratories and connector companies, formulated plans to re-evaluate aluminum conductors. The electrical laboratory re-evaluated the aluminum-core building wires and the connector company re-created new connectors for aluminum-core construction wires. After stringent screening of aluminum core construction wires, the wire and cable company eventually selected the 8000 series aluminum alloy and began to use it in the manufacture of building wires. Among them, the application of the AA-8030 aluminum alloy.
Compared with AA-1350 pure aluminum, AA-8030 aluminum alloy has higher tensile and yield strength, better elongation and softer. In the United States national regulations, it is stipulated that the new alloy AA-8000 series electrical grade aluminum alloy material must be used. By mid-1972, only aluminum core building wires (AWG8, 10, 12) and electrical wiring devices (CO/ALR) that were reconsidered in several specifications were included in the industry standard.
In order to cooperate with and support the R&D work of wire and cable manufacturers, connector companies and electrical laboratories, some wire and cable companies also carried out installation trainings for aluminum core building wires. In addition, the UL standard 486B for aluminum conductors has also been revised and reissued in 1978. At present, some companies are still using AA-1350 pure aluminum conductor connector test, with a view to making a connector for both AA-1350 pure aluminum conductor, also applies to AA-8000 series aluminum alloy conductor.
If you compare the AA-8000 series aluminum alloy with the previous aluminum alloy, from the excellent performance of the AA-8000 series aluminum alloy will find that this aluminum alloy is indeed ideal for the manufacture of a variety of aluminum core construction wire material. It is now possible to manufacture AA-8000 series aluminum alloy wires with specifications of AWG8 and above. In addition to continuing to study the continuity of conductors, new types of aluminum alloy conductor materials with better flexibility, smaller resilience, and easier installation at the site are still being developed.
Timely formulation of standards for product name
In the 1980s, the U.S. electrical industry, including the wire and cable industry, achieved new developments. For product standards, procedures, and technical specifications, electrical grade 8000 series aluminum alloy conductors are all beginning to be cited. In 1981, the American Society of Materials Testing (ASTM) working group began to prepare AA-8000 series aluminum alloy conductor standards. In 1985, a proposal for listing AA-8000 series aluminum alloy conductors in the National Electrical Code (NEC--National Electrical Code) was proposed. In the same year, the Underwriters Laboratories (UL) revised the UL83 standard. In most aluminum-core building wires, AA-8000xilie aluminum alloy conductors are required. In the fall of 1988, ASTM completed the preparation of AA-8000 series aluminum alloy conductor specifications and published ASTM B-800 and ASTM B-801 standards. Since then, AA-8000 series aluminum alloys have been legally used as building wire and cable and power cable conductors and have been rapidly promoted around the world. This situation has continued to this day.
Foreign Products Entering China Cause Strong Cognitive Impact
The progress in the application of aluminum core wire and cable in China is very different from that in the United States. Although China had already identified "aluminum substitute copper" as a national technology policy as early as 1957, due to poor implementation and various other reasons, it has affected the popularization and application of aluminum core and aluminum alloy core wire and cable.
After the reform and opening up, along with the increase of foreign technical exchanges in China's wire and cable industry, foreign wire and cable manufacturers have also come to China to conduct technical discussions, participate in Canton Fairs and professional exhibitions, etc., and have demonstrated advanced aluminum cores and aluminum to China's wire and cable industry. The alloy core wire and cable products, including large-section solid aluminum conductor power cables, have opened the eyes of the people in China. As a result, China's wire and cable industry began to upgrade and upgrade the aluminum core wire and cable.
If we follow the progress of research in the 1980s, the technical level of China's aluminum core and aluminum alloy wire and cable will certainly develop to a considerable extent. However, in the research and development of China's wire and cable products, there is often a fact that can not be ignored, that is: the development of wire and cable installation and installation of gold equipment, always lagging behind the wire and cable itself R & D progress. This phenomenon still exists to varying degrees. For example, due to the backwardness of erection hardware for overhead insulated cables, it has seriously hampered the promotion and export of aerial insulation. The country with the most exported aerial insulated cables in the world is Finland. They are all exported together with erection hardware.
In the past ten years, lead manufacturers such as the United States, Canada, and Germany have introduced aluminum alloy wires and cables into China and achieved great success. Only in this way can the people get a new look and realize that “the original aluminum core cable still has so much knowledge”. Sense of shame and then courage. In recent years, China has successively promulgated the aluminum alloy cable product standards and installation technology standards, and only then began to rapidly develop aluminum alloy wire and cable in China.