Analysis of physical properties of aluminum alloy cable from its physical properties and its applica

& nbsp; cable is an important part of the distribution network, safe operation of the distribution network has a crucial role, so from the aspect of technology focus on cable selection should be emphatically considered the type of cable and conductor material and section area.

Cable type selection is mainly about the use of cable, laying conditions and safety factors. According to different purposes, selection of power cables, overhead insulated cables, control cables etc.; according to the different laying conditions, selection of general plastic insulated cables, steel tape armoured cable, steel wire armored cable, anti-corrosion cable; according to safety requirements, can choose flame-retardant cable, flame-retardant cable, non halogen flame retardant cables, fireproof cables etc..

The selection of the cable conductor section is generally used as a selection condition, such as heating, voltage loss and mechanical strength. According to the experience, low-voltage power line due to the load current is bigger, so the first general according to conditions of the heating section selection and check the voltage loss and mechanical strength; low voltage lighting line because of its high requirements on the voltage level, first according to the permissive voltage loss condition selection section and then checking the hair thermal conditions and mechanical strength.

In the aspect of the material selection of the conductor, because the aluminum conductor has the characteristics of light weight, it is undoubtedly the first choice of the aerial cable insulated cable. From the security requirements of due to aluminum alloy conductor oxidation and corrosion resistance was significantly lower than that of the copper conductor, in high temperature situations, the inflammable and explosive places, particularly humid place and the aluminum corrosion places (such as heat exchange station pump room), personnel gathered more places (such as activity center, business is industry personnel gathered more places), important reference room, computer room, important warehouse (such as the fire control room, weak general room, control room), mobile devices or violent vibration of the places (such as generator room), not to use aluminum alloy electric cable.

Special needs to be pointed out is that distribution network of electrical accidents occurred mostly in the electrical connection parts, cable conductor and the connector (terminal) between stability and reliability of connection for power system is very important. Following further discussion:

In recent years, due to the rise in copper prices and aluminum conductor wire and cable prices low, light weight, reducing the construction labor intensity and welcomed. Aluminum and aluminum alloy conductor has in the wire and cable industry occupies a certain position, according to the survey, a large manufacturer of wire and cable in 2014 to use raw copper 18 million tons, and usage of raw aluminum reached 11 million tons. However, there are many problems in the construction of urban power network in China.

Aluminum or aluminum alloy, whether electrical conductivity and mechanical properties are better than copper, 20 DEG of the DC resistivity 2.82× 10 6 & omega; & bull; cm, about is 1.64 times of that of copper. The electrical conductivity of aluminum is beyond doubt, and the alloy elements such as copper, iron, magnesium and rare earth are only partly mechanical properties, and the conductivity is not increased. Where the annealing process is superb, its electrical conductivity can be very close to electrical aluminum. “ the conductor ” the national standard GB/T3956-2008 will take the same value as the resistance of the aluminum and aluminum alloy conductors. So, theoretically speaking, even if the quality of aluminum alloy conductor, when the conductor cross-section copper conductor section of 1.5 times, in order to achieve the copper conductors with the same electrical performance (ampacity and voltage drop).