Milling Rolls

the basic operating member of rolling machines. They may be solid or hollow, smooth (with a microscopically rough surface) or threaded (with grooves inclined at a slight angle to the generatrix of the cylinder). The rolls generally used for mills are solid and are made of chromium-nickel cast iron that is cast in an iron mold with short press-fitted shafts. Such rolls require static balancing but are very massive; hollow milling rolls must be dynamically balanced (which is more complicated), but their construction permits the use of water cooling, which lowers the surface temperature of the rolls and, to a small extent, of the milled product. The fundamental requirements for milling rolls are high stiffness and an exact geometric shape. The surface Brinell hardness of smooth milling rolls is 320-350, and of grooved rolls, 400-500.