New machining method for “fir-tree” profiles

Delcam is working with Iruba, a German provider of engineered solutions, and machine-tool manufacturer Hermle to develop a novel five-axis machining method, programmed with the PowerMILL CAM system, for the creation of “fir-tree” profiles in components for turbo machinery.  
The new turbo machining process using Delcam’s PowerMILL offers an alternative to broaching.

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 five-axis machining centre, rather than having to use specialist broaching equipment.

More consistent cutting forces
The use of PowerMILL’s trochoidal strategies gives a number of benefits, in particular giving high material removal rates with lower, and more consistent, cutting forces.  The more consistent cutting forces also ensure higher accuracy in the position and in the shape of the slots, with minimal thermal effects on the surface of the profiles.  The process also reduces the number of specialist cutting tools that are required, and cuts the machining time in steel alloys by between 30 and 40 per cent, compared to alternative standard milling solutions, giving a time almost equal to broaching.
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.”

Milling as solution
Mattias Rutschinski, Managing Director of Iruba, added, “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 five-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.”

For further information on Delcam’s PowerMILL software
Peter Dickin, Marketing Manager
Direct phone: 44 (0)121 683 1081
[email protected]

Delcam plc, 
Small Heath Business Park,
Birmingham, B10 0HJ, UK