GCr15 hardened steel is widely used to fabricate various components of roller of high hardness and high resistance to wear which are usually finished machining by grinding process. With the development of fabrication technology, especially of cutter material and machining process, to use ceramic or PCBN cutting tool to numerical control hard-cut is a good process of both environmental benefit and economic benefit, In this text, GCr15 hardened steel welding pipe roller was selected as turning object to syst...