Aluminium is a good thermal and electrical conductor, which has seen it replace copper in many electrical applications. Aluminium provides a lower weight to current-carrying ratio compared to copper. Although in use for several decades in the power distribution sector (i.e. MV and LV cables, as well as OHL and OPGW), the automotive manufacturing represents the brightest growth potential for aluminium wire and cable. As automakers and suppliers continuously look for new solutions to reduce weight, aluminium is a popular candidate for applications that require high current, such as large cables under the hood. Moreover, we may envisage other applications that in the near future will use this metal as the primary conductor core material: from the rolling stock to the off-shore (platform) cables, aeronautics and military. Basically any place where the importance of weight is crucial.

In these posts named “New technology for Al wire drawing”, we will present the latest technical solutions developed by Sampsistemi for the production of round and shaped wire for power cord and the new advancements in multiwire drawing and in-line annealing technologies to guarantee a better quality of the final product.

Aluminium Alloys (AA) are classified by the principal alloying element (EN 573).

Alloy Series Principal Alloying Elements
1xxx Aluminum (99.00% min)
2xxx Copper
3xxx Manganese
4xxx Silicon
5xxx Magnesium
6xxx Magnesium and Silicon
7xxx Zinc
8xxx Other elements (e.g. Fe, Li)
9xxx Unused series

For electrical purposes, alloy series 1xxx, 6xxx and 8xxx are used. Recently, for overhead lines, new aluminium alloys for Low-Sag (LS) and High Temperature Low-Sag (HTLS) conductors have been introduced on the market. Although in use for several decades in the power distribution sector (i.e. MV and LV cables, as well as OHL and OPGW), the automotive manufacturing represents the brightest growth potential for aluminium wire and cable. As automakers and suppliers continuously look for new solutions to reduce weight and costs, aluminium is a popular candidate for replacing copper.

Thanks to the rapid development of reliable connecting systems, the trend for aluminium wire application in automotive cables is rapidly changing. Considering a premium car, where wire harness has a weight of 5-6 kg approx., replacing flexible copper cables with flexible aluminium cables having cross section bigger than 1,5 mm2 can reduce the weight of harness up to 40-45%. The most popular alloys used in automotive cables are 13xx series.

Overhead conductor, power cable and flexible cable manufacturing processes (drawing, stranding and extrusion) can be outlined as shown below.

Aluminum wire drawing

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