Analysis of the Effect of the Threading Head with Axial Compensation on the Axial Force of Advance and Return in the Threading
摘要
The manufacturing of internal and external threads ensures precise and reliable assembly of mechanical components. This process is utilized in various applications, including the production of commercial screws for fastening, spindles for movement transmission, micrometric screws for measuring instruments, and screws used in dental and bone implants. In internal threading, several factors can contribute to the premature breakage of taps, such as material ductility, hardness, machine synchronization errors, excessive cutting speed, dimensional and geometric errors in holes, chips at the bottom of the hole, the lubricity of the cutting oil, tool coating, and the type of threading head used. This investigation analyzes the impact of axial compensation threading heads from different manufacturers on the axial forces during the threading of aluminum alloy AA6063. M8 × 1.25 mm taps, coated with DLC and having a helix angle of 45°, were examined. Machining was performed on a ROMI 1250D CNC machining center with three axes, using two threading heads with different axial compensation from two manufacturers. The tests employed pressurized cutting fluid at 35 kgf.cm−2, with cutting speeds of 40 m.min−1 and 60 m.min−1. Axial force measurements were taken on non-passing threaded holes. A complete factorial design with two factors and two levels was used for statistical analysis, with ANOVA to assess the effects of each factor level. Results indicate that the axial threading head influences the axial force in the process, potentially causing premature breakage of the internal threading tool.