Open-close type 300mm magnetic coil flaw detector

Magnetization - start the electromagnetic field to magnetize the workpiece;

Demagnetization - demagnetization field starts to demagnetize the workpiece;

Over temperature alarm - the coil has a built-in 75 ℃ temperature sensor. When the set temperature is exceeded, it enters the protection state;

Principles of electromagnetism

The magnetizing current forms an electromagnetic field through the surface of ferromagnetic workpiece (AC and half wave DC have skin effect). The existence of defects will cut off the magnetic line of force, form a leakage magnetic field and adsorb magnetic particles. Magnetic particles accumulate to form magnetic marks. The existence of defects can be judged by observing magnetic marks (magnetic marks are actually enlarged defects).

Longitudinal magnetization method

That is, using the coil method, the workpiece is threaded into the coil or placed between the magnetic yoke composed of two coils. When current is applied to the coil, the longitudinal magnetic field is generated in the coil and passes along the long axis of the workpiece to check the circumferential crack.