Wear form and cause analysis of CNC turning tool

Currently, the application range of CNC turning tool has exceeded the ordinary turning tool, the number of CNC turning tool has been all over the industry. However, the CNC lathe tool in the production process often wear phenomenon, which undoubtedly increases the production cost of enterprises. In order to reduce the production cost and improve the production efficiency of the enterprise, it is necessary to understand the wear condition of NC turning tool and find out the reason of repair and maintenance, so as to keep the high efficiency and low cost processing. In this paper, the wear forms and causes of NC turning tools are emphatically analyzed. 

Wear form and cause of CNC turning tool

1.The loss of the front face of the NC turning tool is also called the crescent wear. 

The reason is that when the plastic material is cut at high speed, the rake face is close to the cutting force, and under the action of the cutting force, it is easy to grind into the crescent concave surface. In the initial stage, the cutting conditions can be improved by increasing the tool rake angle, which is beneficial to chip curling and chip breaking. However, as the crater expanded further, the strength of the cutting edge weakened and the cutting edge was broken. When cutting brittle materials or plastic materials, cutting speed is low, cutting thickness is thin,  and pit wear commonly does not occur.

2.The wear of the CNC turning tool tip is the extension of the wear of the tool flank

That is, the wear of the curved surface of the tool tip and the adjacent flank. This is due to the poor heat dissipation conditions of the parts, relatively concentrated force, wear rate is much faster than the flank. Sometimes in the side of the formation of a series of distance equal to the feed rate of small groove, known as groove wear. This is mainly due to the hardened layer and the cutting line on the machined surface. Cutting hard materials with a high tendency to work hardening is particularly liable to cause groove wear. The degree of tool tip wear has different effects on the Surface roughness and machining accuracy of the workpiece.

3. The wear of the back surface of CNC turning tool is caused by the pile-up of the plastic material

when cutting under large cutting thickness, and the back surface of NC turning tool does not contact with the workpiece. In addition, when the flank is in contact with the workpiece, a wear belt with 0 Rake Angle will be formed on the flank. In the middle of the working length of the cutting edge, the wear of the flank is relatively uniform, so it is possible to measure the wear degree of the flank with VB. No matter what type of cutting tool, in different cutting conditions, there will be flank wear, especially cutting thickness of plastic materials or brittle materials. Tool wear mainly comes from the side. It is easy to measure the width of wear band with VB, so VB is often used to express the degree of tool wear. The bigger the V 8 is, the easier it is to increase the cutting force, cause the cutting vibration, affect the wear of the tool tip arc, and finally affect the quality and precision of the machined surface.