» Non-Destructive Testing » Magnetic Particle Testing » Magnetization using the 4-pole method with direct current flow
Magnetization using the 4-pole method with direct current flow
HPT Hirsch Prüftechnik GmbH and Dr.-Ing. Peter Hirsch have worked on the further development of direct current pulsing technology for the magnetic particle testing (MT testing) and demagnetization of steel parts, and have consequently invented the test equipment.
In place of continuous current, steel parts are magnetized or demagnetized using direct current pulsing. In order to reveal cracks or material separations such as fusing or forging defects, these are ideally sprayed with a fluorescent test media, allowing evaluation under a UV LED test lamp even under daylight conditions per EN ISO 9934-1 and documentation with a digital camera.
Using DC-pulse technology instead of continuous current offers the following advantages:
- High performance of testing devices ( testing current up to 25.000 A)
- Much lower energy consumption
- Compact dimensions of testing devices
- Low weight of testing devices
That way mobile testing is possible. MT-testing takes place next to the component. That makes testing of large components easy. MT-testing device and cables connect quickly to the components to be tested and are testing large areas at the component at once. Slow manual scanning of a part for example with a magnetic yoke does not apply.
- Less operator fatigue
Using the compact, lightweight and high performance mobile HPT testing equipment it is possible for the tester to concentrate on his own task in evaluating the visual indications. This can reduce the proportion of complaints considerably. The parts can be subsequently demagnetized directly on site if necessary.
Demagnetization is made using direct current pulses of declining intensity.
