Green grinding stones are made from green silicon carbide, which is more abrasive and 30% more durable than black grinding stones. They are used for grinding of granite, marble and other types of stones. They have 5 / 8-11 thread and can be used with grinders, either dry or wet.The high pressure rail grinding wheel is the abrasive specifically for surface grinding of steel rails. The products are accessories to heavy steel rail grinding machines imported from overseas. They are superior of heavy pressure grinding, high cutting efficiency, and long product life. The manufacture of these wheels is a precise and tightly controlled process, due not only to the inherent safety risks of a spinning disc, but also the composition and uniformity required to prevent that disc from exploding due to the high stresses produced on rotation.