Roll-forming methods for manufacturing roller bearing seal case

A roll-forming manufacturing method of a roller bearing seal case, comprising:

• roll-forming, from a cylindrical ring, a first profiled ring having a first section extending along cylinder axis of the cylindrical ring and a second section extending from the first section inward toward the cylinder axis;
• applying outward pressure to the first section at a corner where it meets the second section, in direction away from the cylinder axis, to round the first section;
• and
• roll-forming, after applying outward pressure to the first section, a second profiled ring from the first profiled ring.