Hydro aluminium trafo strip within a week

Hydro, as a leading supplier of aluminium strip for electrical transformer windings, is taking performance to a new level: with a lead time of just one week, now offered to key customers in Europe – and by improving product reliability with a novel measuring tool.

June 23, 2014

These recent steps top Hydro’s reputation of leadership in quality and expertise, stable metal supply and strong service, in terms of both excellent delivery performance and technical competence.

Being in the business for 30 years, Hydro holds the leading market position and is the most experienced partner for all big producers of electric transformers across Europe, increasing shipments to manufacturers overseas, notably in the Middle East, South America and Australia.

The top product is HYDEC, a 1070 alloy variation which benefits trafo applications with a particularly high conductivity – one more reason to switch to aluminium as the best material for trafo windings.

Aluminium is lighter and more economical than copper. In annealed condition, transformer windings made of HYDEC strip from Hydro guarantee a conductivity value better than 62.7 percent IACS, with a typical value of 63 percent.

At the CWIEME 2014, when the global industry for electrical transformers meets in Berlin from June 24-26, 2014, Hydro will explain how the company achieves the one-week lead time and how it can help in the most efficient solutions built with aluminium.

More reliable products thanks to new burr measurement

Hydro has also achieved advanced reliability of its trafo material when it is slit to width, by measuring the topography of the trimmed edges with a sophisticated electronic device, in contrast to standard practice of manual measurement with micrometer calipers.

Trafo producers insulate the windings of the soft, narrow strip with thin paper layers – where high, sharp edge burrs might penetrate the paper insulation and lead to short circuits of the final transformer.  Hydro’s electronic burr measurement provides much more exact data, so customers are more at ease in producing reliable transformers.

“We strive to make our beautiful and infinite metal the material of choice, in transformers as in other applications of electricity, energy or other engineering,” says Wolfgang Rempe, head of the General Engineering business unit in Hydro. “Strengthening our service to the transformer industry is part of our strategy to enhance our position in products that are more demanding and tailor-made for our customers´ needs.”

Hydro produces aluminium strip for transformer windings at its rolling mill in Karmøy, Norway, directly cast from liquid material. In this process of continuous strip casting, Karmøy is one of the world’s technological leaders. Compared with hot-rolled strip, material produced using this continuous process is characterized by enhanced properties with regard to strength, thermal stability and electrical conductivity.

Furthermore, the metal can be recycled after each use, keeping the same quality – which makes it an infinite metal for responsible, efficient use of resources.

Hydro’s smooth-surface aluminium strip is free from scratches and impurities. “We can supply trafo strip in six different tempers, ensuring the right value of yield and tensile strength, elongation and hardness for the desired solution,” says Kristian Midbøe, sales manager from Hydro in Karmøy. Thicknesses range from 0.30 to 2.50 mm, widths from 25 to 1,500 mm. Paper-interleaving and paper cores, in several diameters, are optional.

The Karmøy rolling mill is certified according to ISO 9001 and ISO 14001 standards.

Updated: October 11, 2016