Experimental investigation of the infeed method and machining parameters of thread cutting on the tool wear in thread milling

Thread has been considered as a widely used technology in the industries. Thread milling is suggested as an alternative process of tapping. Thread milling includes a small tool which follows a helical path. This process includes significant advantages such as threading holes with different diameters using a specific tool. One of the important issues in machining is the tool wear. Besides a noticeable effect on the machining economy, tool wear has a direct impact on the surface roughness and dimensional accuracy of the workpiece. In thread milling, effective parameters on the tool wear include tool angles and geometry, infeed method in thread cutting, feed, and tool rotational speed. Tool wear and infeed method in thread milling have not been subjected in recent investigations. Hence, this research studies the infeed methods and effective parameters of the machining process on the tool wear during thread milling. Experimental results showed increasing of feed from 0.2 to 0.4 mm/rev led to 30 to 40% larger values of tool flank wear. Also, the variation of rotational speed from 500 to 900 rpm increased tool flank wear about 50 to 60%. Two cases of infeed method were employed which were incremental and modified flank infeed. Considering different rotational speeds, the incremental infeed method increased tool life about 100% while the modified flank infeed method achieved 300% higher tool life.