Trough analysing the reason of oil leakage in bearing box of induced draft fan, a new kind of mechanical magnetic oil seal is put forward to prevent oil leakage of induced draft fan.

This paper USES new technique and new structural principle to develop a high efficiency of magnetic oil-filter. Filter performance and it's use are superior to current magnetic oil-filters.

Electrical industry, machinery industry — Ferrite block talc, porcelain material, oil bearing, magnetic material and other metallurgical particles.