XYZ takes to the skies


The Rolls-Royce Precision Machining Facility in Derby manufactures fixtures for intermediate pressure turbine blades. Previously, it subcontracted the machining but wanted to bring this in-house so evaluated a number of 5-axis CNC machining centres to suit its requirements.

Thomas McAllister, Toolroom Manager says, “We chose the XYZ Machine Tools UMC-5X for its price performance metrics. It was installed in December 2022, and we have used it extensively for 3+2 machining giving us accuracies of 10 microns.”

The turbine blade fixtures are all designed to use an Erowa pallet, which is the standard for the factory. Each blade may have nine fixtures to hold it in different orientations according to the operations to be performed such as grinding or die sinking, locating the blade on 8 points all working from the main datum point of the blade design. CAD models for the design of each fixture are programmed in hyperMILL CAM software for the UMC-5X.

Thomas McAllister continues, “The machining requires compound angles and typically we braze supporting pads on the fixture, machining these to suit the individual blade. For the machine, we specified a BLUM tool setter and RMP 600 Renishaw probe; the kinematics option on the control and, the linear roller system for the best area of contact and fastest axis travel. These options enable us to optimise the accuracy of the machine and check that the machined blade supports meet our quality requirements.”

Rolls-Royce’s machine has 30 tool pockets and is using 26 of them to machine its current fixture designs which are used on intermediate pressure blades.

The UMC-5X comes with the Siemens 840DSL Touch Screen control and has full 5 axis capability. Heidenhain RCN238 high resolution rotary scale encoders on the pivot centres give the direct drive C-axis performance of 90 rpm and ±5” accuracy, while the A-axis achieves 45rpm and ±30”. Machine accuracy over 300mm is 6 microns and it includes linear encoders on 3 axes. Other features include dynamic collision monitoring, thermal spindle compensation, spindle vibration supervision and a direct drive spindle. The optional kinematics chosen by Rolls-Royce runs automatically, recalibrating the axes to eliminate errors by taking account of sources of inaccuracy such as temperature variations.

Currently there are around 25,000 XYZ Machines in use in the UK and typically, XYZ Machine Tools can deliver a new UMC-5X within 3 months with many of its other machines in stock for delivery within 2-3 weeks. Comprehensive training and support is provided by its fleet of 16 service engineers located around the country and its team of in-house specialists. Showrooms and training centres are located in Slough, Nuneaton, Huddersfield, Livingston and Sheffield as well as its head office in Burlescombe were it holds around 20,000 different spare parts on the shelf.

Thomas McAllister says, “We manufacture about 40 complex fixtures each year. The UMC-5X will pay for itself in less than 12 months.”

Want to know more about this article?
Ask us below...

This field is for validation purposes and should be left unchanged.