The Importance of Feed Rate and Cutting Speed of CNC Machines

In CNC machines, the feed rate is the speed at which the tool advances along the rotating workpiece, and the unit is usually the distance per spindle revolution. It can also be called the tool engagement speed, which is usually in inches/minute or millimeters/minute for milling operations. For boring and turning operations, measurements can be made in inches per revolution or millimeters per revolution.

The change of feed rate of CNC machines depends on the blank materials (steel, aluminum, stainless steel, etc.), tool materials (high-speed steel cutting tools, metal materials, etc.) and other cutting factors of the machined parts, such as surface finish and characteristics of CNC machines. The quality of processed products depends on the feed rate, so the optimization of feed rate is very important in the process of CNC machine processing.

The relative speed between the machining tool and the workpiece surface of CNC machines is generally called surface speed or cutting speed. It can also be defined as the linear distance (m/min or ft/min) that the cutting tool material moves on the workpiece surface during cutting. The main parameters of NC machine tools, such as power consumption, cutting temperature and tool life, are determined by cutting speed. The cutting speed value will vary according to different materials (such as high carbon steel, low carbon steel, aluminum and plastic). Some tools or processes, such as thread tools and knurling tools, will run at a cutting speed lower than the above speed.