【Summary description】 The National Energy Administration website released No. 3 announcement in 2015, "Rated voltage 0.6/1kV aluminum alloy conductor crosslinked polyethylene insulated cable"

Notice No. 3, 2015, was released on the website of the National Energy Administration. The industry standard "Aluminum Alloy Conductor Crosslinked polyethylene insulated Cable with Rated Voltage 0.6/1kV" (standard No. NB/T 42051-2015) has been officially approved on April 2, 2015, and will be officially implemented on September 1, 2015. This standard is jointly prepared by Shanghai Cable Research Institute and several enterprises including Shenzhen Shenzhanyao Technology Co., LTD. It is the most authoritative and important standard in the aluminum alloy cable industry so far. It was prepared in 2012, and after three years of repeated revision and deliberation, it was finally approved, promulgated and implemented. It is of great significance to the future development of aluminum alloy cable in our country! Through the study of the standard, the author got some experience, especially share with peers, improper place, please criticize!
First, the standard abandoned the "rare earth high ferric aluminum alloy cable" : the industry standard clearly specifies the chemical formula of six aluminum alloys for cable conductors, which is obviously followed by the six formulas in the American ASTM standard (referred to as AA8000 series aluminum alloys), which may be based on the following considerations: 1. Aluminum alloy cable has been applied in the United States for nearly 50 years, and the six formulas in ASTM standard have passed the test of time. There are a lot of engineering cases of AA8000 series aluminum alloy cable in the United States for more than 40 years. Made a "AA8000 series aluminum alloy cable full life cycle research report", the report with detailed data, scientific analysis, the AA8000 series aluminum alloy cable safety and reliability and service life of more than 40 years and other scientific conclusions! 2. The concept of "rare earth high iron aluminum alloy cable" has been questioned by many experts since its launch, for the following reasons: First of all, rare earth is not a single element. In the formula table of rare earth high iron aluminum alloy, the types of trace elements of rare earth added in the two formulas are different, and the specific basis of detection is not clear. Secondly, high iron will have an uncertain impact on the improvement of the electrical performance of aluminum alloy conductors! Therefore, this industry standard does not include rare earth high iron aluminum alloy cable. 3. In the world (mainly in China), there are not enough application cases to prove the service life and long-term safety and reliability of rare earth high ferric aluminum alloy cable. The chemical composition of this product is quite different from the provisions of ASTM standard.
Two, once again clear the expression of aluminum alloy cable: although the cable national standard GB12706-2008 clearly specifies the expression of the cable must be: insulation + conductor + sheath, but there are still some enterprises with TC90, AC90 to indicate aluminum alloy cable. In addition, about aluminum alloy conductors, some use LH, some use HL, and some use LHB to express, aluminum alloy armor with 5, some use 8, and some use 9 to express, industry standards on all of the above are clearly stipulated, especially no longer allowed to use TC90, AC90 and other expression methods.
Three, the mandatory provisions on aluminum alloy conductor: industry standards in aluminum alloy conductor clear the following provisions: 1, meet the requirements of GB/T 3956-2008: this is to use the original conductor national standard, seamless connection with the original national standard; 2, tensile strength and elongation at break provisions: this is a supplement to the original national standards, is the mandatory requirements of aluminum alloy conductor; 3. Chemical composition provisions, which are not in the original national standards, are also mandatory requirements for aluminum alloy conductors; 4, neutral line and protection line conductor nominal area provisions: according to this provision will not appear 3*120+1*50 and 4*185+1*120 and other different structure of the core, as long as the nominal core area is determined, you can determine the nominal cross-sectional area of the conductor of the neutral line and protection line.
The following aluminum alloy cable type test from a side, to do a simple interpretation of the standard. type tests are defined as tests to be carried out prior to supply of a type of cable included in this standard in order to demonstrate satisfactory performance of the cable in accordance with the expected conditions of use in accordance with general commercial principles. (Note: The characteristic of this test is that it does not need to be repeated after it has been done, unless a change in cable material or design or manufacturing process may alter the characteristics of the cable.) It is not difficult to see from the above definition that type test is a relatively comprehensive product test, which can better reflect the quality of the product. One type of cable only needs to be tested once. Aluminum alloy cable industry standard (NB/T 42051-2015) is based on the original national cable standard (GBT12706-2008), adding the technical requirements for aluminum alloy conductor and aluminum alloy armor. This is very clear from the comparison of type tests. Type test is divided into electrical type test and non-electrical type test. In NB/T 42051-2015, compared with GBT12706-2008, the electrical type test reduces the "insulation resistance measurement at ambient temperature", and retains the "insulation resistance measurement at the highest conductor temperature during normal operation" and "4h voltage test". NB/T 42051-2015, non-electrical type test requirements retain GBT12706-2008 five categories of 18 test requirements: 1, size (1 item); 2. Mechanical properties (tensile strength and elongation at break) (3 items); 3. Thermoplastic energy (2 items); 4. Other kinds of experiments (6); 5. Non-delayed combustion test (6 items). On this basis, NB/T42051-2015 added 16 new test requirements in the following three categories: 1. Single wire test of aluminum alloy (4 items) : tensile strength and elongation at break of single wire of aluminum alloy; The bending property of aluminum alloy single wire; Aluminum alloy conductor composition; Single line pressure creep test of aluminum alloy. 2, armored layer detection (6) : armored layer of the inner surface inspection; Tightness of armor layer; The flexibility of armor layer; Tension of armoring layer; Elongation of armor layer; Thickness of armor layer; 3. Finished cable test (6 items) : low-temperature flexibility of finished cable; Extrusion pressure at room temperature; Shock at room temperature; Finished cable bending test; Finished cable system connectivity test; Salt spray test for finished cables. From the above analysis, it can be seen that the industry standard (NB/T 42051-2015) technically guarantees the quality of aluminum alloy cable, improves the industry level and entry threshold of aluminum alloy cable, and fundamentally puts an end to "shanzhai" enterprises. It will certainly play a milestone significance for the development of aluminum alloy cable market!