HPT Hirsch Prueftechnik GmbH develops and supplies mobile and stationary MT-testing and demagnetization equipment. HPT Hirsch Prueftechnik GmbH utilizes AC/DC Pulse Technology for surface crack detection and demagnetization of steel components for industrial applications. There are several important advantages of MT-testing with AC/DC Pulse Technology. For example, it produces crack indications without false indications for unconventionally large test areas within a very short period of time. Therefore, even large components like forged rings and gears with diameters up to 10 m for wind power plants, shafts, and casted or welded components can be quickly MT-tested and/or demagnetized.