Experimental Analysis of a Novel Rotary Ultrasonic Assisted Drilling (RUAD) Machine

Ultrasonic assisted drilling (UAD) is an advanced technology, with proved benefits on drilling quality and productivity, in particular for the materials with low machining properties, such as super alloys. However, it suffers from the limitations incurred by the rotation incapability of the vibrating tool. In this research, this major drawback is overcome by improving the system thorough providing rotational capability to the vibrating tool. Consequently, this advanced drilling technology can be used for any industrial part, regardless of its size and the location of the hole. An innovative mechanism is designed, which utilizes an ultrasonic transducer to axially vibrate the drilling tool, while it is simultaneously rotating. It is actually a portable tool holder interface, which can easily be installed in different machines. Unlike prior work, the brush mechanism is readily accessible for required repair and maintenance. Once the setup is prepared, a set of accurately designed experiments and associated statistical studies are carried out using factorial design of experiment (DOE). Spindle speed, feed rate, and the vibration amplitude are taken as input factors, while surface roughness, circularity, and cylindricity are studied as output parameters. The obtained results are quite encouraging, showing that all the benefits of UAD are achieved in the new system, while its major limitation is overcome.