New fir tree root milling process from Delcam, Hermle and Iruba challenges broaching

The new process, which provides an alternative to broaching, was demonstrated to "an enthusiastic response", during last year's IMTS exhibition in Chicago, Delcam reports. The milling approach, which is based on the trochoidal machining strategies in PowerMILL, has been patented by Iruba. It allows complex 'fir-tree' profiles to be produced on milling machines, such as the Hermle C60 5-axis machining centre, rather than having to use specialist broaching equipment. Compared to alternative standard milling solutions, the process reduces the number of specialist cutting tools that are required and cuts the machining time in steel alloys by between 30 and 40%, giving a time almost equal to broaching. Mattias Rutschinski, managing director of Iruba, said: "At IMTS, we presented, with Hermle and Delcam, a world premiere by milling small fir-tree geometries in IN718, a typical material for aero-engine parts. The presentation impressed our visitors and made it very clear that milling is the more effective technology, since we could mill even curved slots, deburr them and measure them in one process on Hermle's smallest 5-axis machine, the C22. "Broaching is a technology developed at the end of the 19th century," concluded Mr Rutschinski. "Many applications can be completed today with much lower power consumption and oil waste, by much more integrated and flexible solutions, fitting the production demands of the 21st century." Commenting on the process, Brett Hopkins, manager of Delcam Professional Services North America, said: "We are pleased to be working with other leaders in manufacturing technology, like Hermle and Iruba, to develop this innovative technology. The collective collaboration began several months ago and was received with great enthusiasm when we presented the process at IMTS."