Ball Valve Grinding & Lapping Machine. Conventional Type Ball Valve Grinding machine Ball Grinder . Key Features: Designed to grind a variety materials of the ball,carbon steel, stainless steel,tungsten carbide coating etc. A105,A182 F304,A182 F316, A 182 F304L, A182 F316L, 17-4PH,MONEL, F51, ceramic balls etc . Size range:2''-20'' DN50-DN500