[Chinalco News] Currently, aluminum alloy cables have been gradually recognized by the market, and more and more users plan to use aluminum alloy cables. However, due to the lag of standards and supervision, it is difficult to distinguish between good and bad in the market! Many enterprises without aluminum alloy cable production technology and equipment are also promoting aluminum alloy cables, which has brought great confusion to users' choice. Here are some standards for users to refer to when selecting manufacturers and products, so as to select truly high-quality aluminum alloy cables. First of all, enterprises specializing in the production of aluminum alloy cables should be selected as far as possible. Such enterprises only focus on the research and production of alloy cables. They are more professional in technology, more mature in production technology and process, more complete in production equipment, better in technical services, and more professional, dedicated and dedicated, which can be more excellent. The following 10 standards, including production technology, equipment, process maturity, industry standards and test reports, are used to identify aluminum alloy cable manufacturers for reference:

Inspection standard I: product quality

Aluminum alloy cable is mainly composed of conductor, insulation and armor (sheath). Based on the analysis of the three basic elements of aluminum alloy cable, we can see the quality of aluminum alloy cable.

（1） Aluminum alloy conductor rod: see if we can independently produce high-quality aluminum alloy conductor rod

At present, there are few manufacturers with independent aluminum alloy conductor production technology in China, and even fewer aluminum alloy conductor rod production lines capable of continuous smelting, continuous casting, continuous casting and rolling. If they do not have independent aluminum alloy conductor rod production capacity, relying on entrusted processing, so-called secret smelting, or other aluminum alloy conductor rod materials purchased without formal sources, not only cannot guarantee the basic quality of aluminum alloy cables, It is also impossible to control the cable quality from the source. In addition to the aluminum alloy conductor rod production line with melting, continuous casting, continuous casting and rolling, it also depends on the size of the continuous casting billet cross section of the production line. The larger the cross section is, the better the quality of the aluminum alloy rod will be. The excellent aluminum alloy conductor rod is the decisive factor for the electrical and mechanical properties of aluminum alloy cables. Without high-quality aluminum alloy rod, the basic quality of its conductor cannot be changed in the subsequent process, no matter how drawing, twisting, cabling, armouring, etc.

（2） Insulation: there are three aspects about insulation; Crosslinking degree, stranded conductor, conductor cabling annealing

(1) Crosslinking degree; One of the advantages of aluminum alloy cable over copper cable is that all aluminum alloy cables are insulated with cross-linked polyethylene, and the working temperature of the cable is 90 ° C. Because cross-linked polyethylene insulation is adopted, there is a problem of cross-linking degree. Formal professional aluminum alloy cable manufacturers should have special cross-linking rooms.

(2) Stranded conductor; Judging from the conductor stranding technology and conductor stranding production line, the stranding conductor equipment in the domestic cable industry is basically the same at present. The twisted conductors produced usually produce aluminum chips and burrs, damage the insulation, affect the insulation effect, cause safety hazards and shorten the insulation life. The most advanced stranding conductor equipment is the sub motor type, PLC program controlled nanotechnology conductor stranding equipment. With this advanced process equipment, microcomputer controlled production programming, and innovative top-level nanotechnology, the aluminum alloy conductor surface produced is free of aluminum chips, burrs, oil stains, bumps, scratches, and scratches, which can most effectively ensure that the cable insulation is free of any damage and damage, Ensure that the service life of the product is much longer than that of similar products.

(3) Conductor cabling annealing: usually, the internal stress existing in the stranded conductor after the conductor is stranded will be applied to the insulation, which will make the insulation subject to long-term stress, accelerate the insulation aging, affect the service life of the insulation, and thus directly affect the service life of the cable. This is the reason why the service life of the copper cable is not long. Aluminum alloy production plants in the United States all adopt the conductor cable annealing process to solve the internal stress problem. The cable forming annealing technology can further improve the electrical and mechanical properties of the product, eliminate the internal stress generated in the conductor stranding process, and effectively ensure the service life of the insulation. Therefore, it must be seen whether there is cable annealing process technology and conductor cable annealing furnace equipment.

（3） Armor: see if there is advanced aluminum alloy interlocking armor equipment

The aluminum alloy armouring of many domestic manufacturers is not up to standard due to the poor equipment level and process level, so that the alloy belt is wide and the distance between armouring peaks is large, resulting in rigid cables, inflexible bending, easy armor stripping, poor compression resistance and poor effect. At present, the most advanced aluminum alloy interlocking armor equipment is the KALMARK aluminum alloy interlocking armor production line in Canada. The interlocking armor produced by this equipment has good tightness, and the armor is interlocked with each other, making it difficult to detach. Due to the small spacing between armouring crests, armouring with the same distance has more stress points than other armouring products, which can withstand greater pressure without damaging the cable core. As there are many wave peaks, the bending radius is smaller, and the bending resistance is better. This aluminum alloy armouring can truly meet the requirements of American standards for aluminum alloy armouring.

Inspection standard 2: manufacturing equipment

Mainly investigate whether the enterprise has advanced aluminum alloy cable production and manufacturing equipment and technical process equipment.

(1) Continuous casting and rolling production line for aluminum alloy conductor rod

The key of aluminum alloy cable is the production of aluminum alloy conductor. Therefore, when selecting manufacturers, we should first check whether there is an advanced continuous casting and rolling production line for aluminum alloy conductor rods. At present, the most advanced production equipment for aluminum alloy conductor rods in China is a continuous casting and rolling production line with Italian technology that can continuously cast large sections (3807mm2, and the maximum casting section of other production lines imported from Italy can only reach 2400mm2), The 3807mm2 aluminum alloy casting billet can obtain aluminum alloy rods with moderate strength, large bulk density, best conductivity and the best technical indicators after repeated tempering, continuous rough rolling with large compression ratio and multiple passes of continuous fine rolling. The alloy wire drawn from this aluminum alloy rod is used for the conductive core of aluminum alloy cable conductor, which is the best product for cable superposition and combination. If a factory does not have an advanced aluminum alloy conductor rod continuous casting and rolling production line, the quality of aluminum alloy conductor cannot be controlled from the source of production, and the quality of aluminum alloy cable cannot be guaranteed!

(2) Conductor stranding production line

At present, the stranded conductors produced by the conductor stranding production line of general domestic manufacturers usually produce aluminum chips and burrs, which damage the insulation, seriously affect the insulation effect, cause potential safety hazards and shorten the insulation life. At present, the most advanced conductor stranding production line in China is a sub motor and PLC program controlled nano stranding machine production line. The aluminum alloy conductor surface produced by nanotechnology is free of aluminum chips, burrs, oil stains, bumps, scratches and scratches, which can most effectively ensure that the cable insulation is free of any damage and damage, and ensure that the service life of the product is much longer than that of similar products.

(3) Aluminum alloy interlocking armor production line

At present, the world's most advanced aluminum alloy interlocking armouring machine production line is the KALMARK aluminum alloy interlocking armouring machine production line in Canada. The aluminum alloy strip interlocking armouring cable developed by this production line according to the American technical standards has a special structure of layer to layer interlocking that can ensure that the cable can withstand strong external force damage, even if the cable suffers from large external pressure and external impact, The armor layer can also protect the electrical performance of the insulation layer. The structure of the aluminum alloy non-magnetic armor layer also effectively improves the flame retardant level of the cable, greatly reduces the harm of fire or fire to the cable, and the non-magnetic aluminum alloy armor also greatly reduces the eddy current loss of the cable. Compared with steel strip armouring, aluminum alloy strip armouring structure is light in weight, no eddy current loss, convenient in laying, easy to bend, and does not require bridge installation, which can reduce the installation cost by 20% - 30% and improve the installation efficiency.

Inspection standard III: test report

It mainly inspects whether the products of the enterprise have been tested and certified by the national authority on product characteristics, fire resistance, flame retardancy, smoke toxicity, light transmittance, etc.

(1) Three necessary technical reports: Inspection Report on Aluminum Alloy Conductor Materials, Test Report on Compressive Creep Properties of Aluminum Alloy Conductor, and Test Report on 1000 Thermal Cycles of Transition Terminals. The first is the report on whether the aluminum alloy conductor material meets the chemical composition requirements of AA8000, the second is the report on the direct differentiation of aluminum alloy from pure aluminum, and the third is the report on the reliability of connecting terminals. These three technical reports are required for qualified aluminum alloy cables.

(2) The inspection report of aluminum alloy cable products issued by China National Wire and Cable Testing Center, Wuhan High Voltage Research Institute of State Grid and other national inspection institutions.

(3) Test reports on fire resistance, flame retardancy, smoke toxicity and light transmittance of products issued by the National Quality Supervision and Inspection Center for Fire resistant Building Materials.

(4) When selecting halogen-free low smoke products, special attention should be paid to the inspection report on smoke toxicity and light transmittance issued by the National Quality Supervision and Inspection Center for Fire resistant Building Materials; At present, many domestic manufacturers claim to produce halogen-free low smoke aluminum alloy cables, but the materials used in actual products can not meet the requirements of halogen-free low smoke, which can be seen from the test report. The national standard (GB/T20285-2006 Classification of Smoke Toxicity Hazards of Materials) specifies the safety level of smoke toxicity detection; Smoke toxicity safety: AQ1 ＞ AQ2 ＞ ZA1 ＞ ZA2 ＞ ZA3 ＞ WX; The light transmittance shall be greater than 60%, of which (AQ: safety level, ZA: quasi safety level, WX: danger level). The detection results of aluminum alloy products show that only those whose smoke toxicity index reaches AQ level and whose light transmittance is greater than 60% are truly halogen-free and low smoke products, which are truly safe and reliable. Even if the cable is burned, it will not release toxic gas, and the laying, installation and use are safe.

(5) As for other so-called evaluation reports and industry certificates, in fact, some enterprises are playing tricks. As we all know, these things are issued by consulting and intermediary agencies run by some industry departments. As long as you pay the fees, it is not difficult to get them. These reports, certificates, etc. cannot explain or prove anything about product quality, and are not enough for reference.

Criteria 4: Independent intellectual property rights and technical patents

Aluminum alloy cable is a new conductor material product in China. The current standard does not have special provisions for aluminum alloy conductor material. In order to avoid that the source of material technology is unknown, resulting in the performance and quality of aluminum alloy cable products can not be guaranteed, the selected manufacturer must have the independent intellectual property patent certificate of the conductor material and manufacturing technology. Whether an enterprise has the core aluminum alloy conductor smelting formula and proprietary technology and independent intellectual property rights is the basic condition for an enterprise to have strong technical strength. As we all know, without the core technology of aluminum alloy conductor, no matter how loud the advertisement is, it is difficult to ensure that it is authentic aluminum alloy cable. The aluminum alloy formula, the core technology with invention patents, is the primary premise for smelting, casting billets and rolling bars in the first process of aluminum alloy conductor production. Without a real aluminum alloy invention patent formula, no matter how advanced the continuous casting and rolling process equipment is, it will not help. The patent formula of aluminum alloy material is the precondition for the implementation of high-level aluminum alloy cable processing, manufacturing and process technology, the guarantee of excellent aluminum alloy cable quality, and the real technical advantage of an enterprise.

Inspection standard V: quality control

Cable is the artery of energy transmission, which is related to the safe and stable operation of power transmission of an enterprise or even a region. The quality of aluminum alloy cable is crucial, and it can not be careless. The production process of aluminum alloy cable is very different from that of copper cable. The production of aluminum alloy cable requires a lot of professional testing equipment and a perfect quality management system. Each batch of aluminum alloy cables can be delivered only after strict detection and inspection in all production links. To investigate the attitude of a manufacturer towards quality control, it can be seen from the personnel, funds and institutions invested that a professional aluminum alloy cable manufacturer should have a special quality management office, chemical analysis laboratory, mechanical performance laboratory, physical performance laboratory, spectral analysis laboratory, electrical performance laboratory, etc. Excellent enterprise quality control is from smelting alloy aluminum liquid to continuous casting and rolling; From aluminum alloy rod wire drawing, compact stranding to conductor heat treatment; From conductor insulation extrusion and cross-linking to insulation core cabling; Finally, each process of armouring, sheathing, routine test, packaging and delivery has a perfect and strict tracking inspection, that is, control from the source to ensure the highest quality of finished cables. The whole process quality control shall be carried out for the products produced, and the time node shall be accurate to every minute and second, and corresponding marks shall be made in the aluminum alloy cable structure to ensure the traceability of the quality control of each inch of aluminum alloy cable. One of the most important testing equipment among many testing equipment is aluminum alloy conductor material testing equipment. At present, the most advanced aluminum alloy conductor material testing equipment in the world is the full spectrum direct reading plasma emission spectrometer in Germany, which has the fastest detection speed and highest accuracy. Spectrometer is mainly used to detect the chemical composition of aluminum alloy materials and the crystalline state of alloys. Without advanced testing equipment, the quality of aluminum alloy conductor cannot be guaranteed!

Investigation standard VI: Technical standard

The national industry standard of aluminum alloy cable has been submitted to the national competent department for approval. If it is a company that participates in the formulation of national standards and specializes in the production of aluminum alloy cable, it must be a leading enterprise with strength and influence in the industry. The United States is the birthplace of aluminum alloy cable. The manufacturing technology and installation experience of aluminum alloy cable in the United States are more than 40 years ahead of that in China. Therefore, objectively speaking, American companies, In particular, aluminum alloy cable manufacturers that first introduced aluminum alloy cable technology from the United States and used American standards to manufacture aluminum alloy cables will ensure safety and reliability.

Assessment standard 7: customer case

The application scope of aluminum alloy cables covers residential, commercial, industrial buildings and other fields. The feedback from customers is of great reference value. We should focus on the operation and after-sales maintenance of aluminum alloy cables used by customers. If the customer's cables have problems at both ends of the day, the manufacturer should carry out after-sales maintenance, indicating that the cable quality needs to be studied. A quick way to judge the manufacturer of aluminum alloy cables is to investigate the power design unit. If an electrical engineering consulting and design unit uses aluminum alloy cables for power transmission of its own building projects, the supplier and products must have been fully and closely scientifically demonstrated and can be selected at ease.

Assessment standard 8: value-added services

General domestic enterprises use the idea of copper cable to make aluminum alloy cable. Aluminum alloy cable is only one of their product series. The idea of operating aluminum alloy cable is also to follow the idea of copper cable and simply sell cables. Nowadays, selling aluminum alloy cables with the idea of simply selling cables does not meet the requirements of the times and social development. The production of aluminum alloy cables has a high technical threshold. A powerful aluminum alloy cable manufacturer should not only be able to provide the best aluminum alloy cable products, but also be able to provide a complete set of cable transmission solutions, cable connection terminal solutions, It also helps customers make technical and commercial solutions such as Project Technical Solutions and Product Life Cycle Cost Analysis Report, and helps customers provide additional value-added services such as cable selection, installation guidance, personnel training, and operation monitoring. It is difficult for enterprises without professional strength, attention to the aluminum alloy cable industry, and an attitude to long-term service for aluminum alloy cable users.