At the Coil Winding Exhibition 2013, C D Wälzholz introduced high-strength (HS) grades of non-grain orientated electrical strip NO 20 to 30 (non-oriented in thicknesses between 0.20 and 0.30 mm thick) which are especially developed for electrical drives in automobiles.
These enhanced materials ensure a high stability of the rotor packets in the e-drive due to their increased strength. At the same time, material technicians at the company in Hagen, Germany were able to further reduce power losses with the same thicknesses of NO sheet and thus increase performance.
Electric drives in the automotive industry differ from classic industrial drives since the frequency range is up to 1000Hz whereas nominal frequencies in industrial drives are between 50 and 60Hz. These particular requirements can only be met by steel materials with lowered thicknesses and chemical composition. The NO 20 to 30 grades meet these requirements.
Another product was also introduced. In cooperation with a lacquer and paint varnish supplier, C D Wälzholz has further developed a special coating system for the automotive industry that allows for individual sheet lamination fins to be baked together to form entire packages. This so-called thermosetting Backlack varnish, offers customers a bonding technology that makes refinishing operations unnecessary and ensures a particular tightness of the lamination fin packages due to their high adhesive strength.