Relationship Between Measurement of Cutting Force and Sensor Location in Turning Process

Turning process is widely used in the production of components for automotive and aerospace applications. The machinability of a work material is commonly assessed in terms of cutting tool life, surface finish, and cutting force. These responses are dependent on machining parameters such as cutting speed, feed rate, and depth of cut. In this study, the relationships between cutting force, cutting speed, and sensor location in the turning process were investigated. Strain gauge was chosen as the sensor for the detection of cutting force signal during turning of hardened plain carbon steel JIS S45C. Two strain gauges were mounted on a tool holder at a defined location of I, II, or III at a distance of 37, 42, or 47 mm, respectively, from the cutting point. Only one set of machining experiments was conducted at spindle speed N = 1000 rpm, feed f = 0.25 mm/rev, and depth of cut d = 0.80 mm. The turning process was stopped and the insert was discarded when average flank wear reached VBm 0.30 mm. The main cutting force F-y and the feed F-x force for each cycle measured by the strain gauges at location I, II, and III were collected and analyzed. Results show that when cutting speed V was increased, the main cutting force and the feed force F-x were decreased accordingly. The change of F-y was inversely proportional to the change of cutting speed, but the F-x did not decrease continuously and behaved contrarily. A strain gauge placed at a distance of approximately 43 mm from the cutting point was found to be the best and most suitable for sensing accurate force signals.