Your English is very good, better than some Americans that have been living here their whole life!!
Bead blasting is the same as sand blasting, using an air compressor to shoot sand (or beads, crushed walnut shells...among other abrasives)
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I don't have one of these setups, but I use a Dremel with a wire wheel to clean the area and the mag rot, then I fill it with JB Weld. After it dries, sand it, prime it and then paint it.
A sand/bead blasting setup will speed up the process and probably do a more effective/efficient job at it.