Magnetic particle inspection is used to locate discontinuities on or near the surface of ferromagnetic materials. A magnetic field is induced in the part to be examined. Discontinuities at or near the surface will cause the magnetic field to concentrate. Fine magnetic particles are attracted to the magnetic field leakage over the discontinuities forming indications or mapping the discontinuities. Considerable theory, technical training, specialized equipment and trial and error is involved for effective magnetic particle inspection.
There are two types of materials generally used for magnetic particle inspection, wet method and dry method. Dry method materials are primarily used in weld inspection. Production and overhaul situations require high sensitivity, and broad detection capability is best achieved by the wet method. Wet method particles are generally smaller than dry method particles and are more easily attracted to weaker leakage fields. The particles are suspended in a liquid carrier fluid which facilitates the mobility of the particles on the part surface. The particles can be of visible or fluorescent illumination.
Wet method materials may be used with AC, HWDC, or FWDC magnetizing currents. In all three the application of the bath begins and ends before the current shot is ended to insure maximum field strength during bath application. Bath application after the current shot may reduce sensitivity by washing off weakly held particles. Most dry method particle inspections use AC magnetization.
Special petroleum based carrier fluids or water which has been treated with conditioning agents may be used as the wet method particle bath media. The bath must be continuously agitated during use as the dense particles will settle out of solution upon standing. Materials intended for water bath use should not be placed in equipment that has been used for oil bath applications until the tank and all plumbing have been thoroughly cleaned.
R-CON NDT offers Wet Bath units, Mobile Mag units and Portable Mag units. We also offer all consumables for Magnetic particle including wet and dry mag.
R-CON NDT is proud to represent Gould-Bass Magnaflux and Parker magnetic particle inspection equipment and accessories. Magnaflux is an industry leader in the manufacturing of Wet Horizontal units. Both single directional and multi-directional units are available. Gould-Bass also manufacturers mobile and portable inspection units.
R-CON NDT offers Circle, Magnaflux, Met-L-Chek, and Sherwin consumables such as Carrier, Wet Particles, and Dusting powders.
R-CON NDT is proud to represent Magnaflux and Gould-Bass magnetic particle inspection equipment and accessories. Magnaflux is an industry leader in the manufacturing of Wet Horizontal units. Both single directional and multi-directional units are available. Gould-Bass also manufacturers mobile and portable inspection units.