PowerMill’s dedicated Blade, Blisk and Impeller (BBI) tool axis control and smoothing algorithms coupled with automatic collision avoidance and verification made the programming experience faster and easier with few iterations and minimal post-calculation editing required. Typically these cutter types can be difficult to program and control due to a combination of the large radius cutter form and desire to minimize the tool-axis motion whilst avoiding holder collisions with the part. The Barrel form enables a greater stepover to be achieved and cycle times to be reduced. Barrel type roughing and finishing cutters were then used to finish the part. This approach was modified to use a slotting operation to cut out each aerofoil profile removing the maximum amount of material in as little time as possible to produce a near-net shape. The toolpath combination and approach used was completely different from the conventional approach which would traditionally comprise of many shallow but fast cutting passes and be limited to Ball cutter types. These unpredictable forces result in either inconsistent material conditions or machining marks being left on the aerofoil surface. This results in a constant push/pull effect on the material and aerofoil being machined. In particular, the motion of and load on the cutter is constantly changing.
Aerofoils are typically tall and thin and so they move and vibrate during the machining cycle which causes problems. To achieve this all aspects of the machining process were considered not only the cutting strategy but also the machine tool, fixturing, cutters and cutter holders too.īlisk aerofoil toolpaths usually consist of many shallow roughing, semi-finishing and finishing passes utilizing ball nosed cutters. GCD’s intent was to make a huge reduction in machining cycle time. Pre-Turned forging blank, this is the input condition to the 35 hour machining cycle time Baseline cycle time at Autodesk facility: 135 hours.31 Blades: 120mm high, 84mm chord length.
During the project close-out review the GCD team wondered what could be achieved without any such limitations how far could the software and hardware be pushed and how much could the machining cycle times be reduced? Beyond limits However, even with these limitations, by using powerful machining strategies within Fusion 360 with PowerMill the customers machining cycle time was reduced by 40% and the project goals successfully met. Given the constraints imposed, the overall benefit was limited. Maintaining cutter consistency prevents this revalidation being required and thus the process improvements could be implemented immediately. The reason for this is that aerospace components and their defined manufacturing processes are tightly controlled any changes must go through lengthy validation processes. The constraint was that customer did not wish for the cutting tool suite to be changed, especially for finishing. The customer’s objective was simple cut costs by reducing machining cycle time. Toolpath optimisations to increase customer productivityĪdvancements in CAM and increasingly capable machine tools have enabled Blisk technology to become more readily available for use in commercial aeroengines.Īutodesk’s Global Consulting Delivery (GCD) team were contracted by an aerospace manufacturing company to deliver process development improvements on their Blisk production. Blisks have traditionally only been found on military aeroengines, for example the low-pressure combustion stages of the EJ200 Euro Fighter and the F35 Lighting II – Joint Strike Fighter due to manufacturing complexity and associated costs.
It is a single piece component comprised of a ring of aerofoil blades arranged around a central hub where the Blisk generates rotational motion from the force of air blowing through an aeroengine. The word ‘Blisk’ is a portmanteau of ‘Bladed Disk’. Architecture, Engineering and Construction.Architecture, Engineering & Construction.