||For certain applications, hard turning can deliver tolerances and surface finishes that make grinding unnecessary. For extremely tight-tolerance jobs, hard turning can also serve as an effective pre-finishing operation. It is generally applied when work pieces are harder than 45 Rc.
Using turning centers to cut part blanks that have been work hardened offers several advantages including the ability to reduce and even eliminate some finish grinding. With hard turning, the intermediate step of heat treating is eliminated from the work piece flow.