Full Steam Ahead At Starrag For Turbine Technology Developments

Year on year, Starrag’s Turbine Technology Days never fail to impress – and the 2018 edition, the sixth in the annual series, was no exception as it showcased developments to further improve the efficiency of machining turbine blades, blisks and engine casings, including:

[] A flexible manufacturing system featuring 11 Starrag NB 151 machines, for automated blisk manufacture;

[] A toolchanging angle head – a joint development with Benz – where a single head with HSK-B63 interface can replace the use of multiple angle heads; and

[] Adaptive roughing of turbine blades, to eliminate ‘air cuts’, by using in-machine probing in conjunction with Starrag’s RCS programming routines.

Also previewed was Starrag’s new larger capacity NB 151 blisk machine – for components up to 600 mm diameter – as well as the ultra high-accuracy Bumotec s191 mill-turn centre that was demonstrated machining aero-engine fuel injectors.

The two-day event at the company’s headquarters in Rorschach, Switzerland, attracted an audience of more than 160 aero-manufacturing professionals from all corners of the globe and it allowed Starrag’s recently-appointed CEO, Dr Christian Walti, to lay down a marker of what Starrag and its comprehensive group product ranges will likely have in store for the future.

“Starrag’s broad product portfolio and inherent expertise is a distinct advantage in terms of global operational excellence,” he said, “and, going forwards, the quest will be to continue to build on that knowledge for the benefit of all our customers.

“As well as leveraging even further efficiencies in collaboration between our sites – for example, perhaps in our supply chain agreements – the strategy will be to maintain similar levels of excellence in terms of the machining solutions supplied and the back-up service provided.”

He added: “The technology advancements being demonstrated here reflect how we are continuously responding to the needs of our customers. Indeed, the aerospace industry is not only constantly presenting opportunities, but for us it is also a case of demonstrating how Starrag is best-placed to satisfy those demands now and in the future.”

This year’s Turbine Technology Days – supported by tooling specialist Haimer, as well as by a number of other industrial partners – continued its relentless quest for superlative manufacturing solutions for blades, blisks and casings, and a series of workstations gave visitors exclusive insights into how such workpieces can be machined most effectively and efficiently.

While individual technologies were showcased, as always the underlying theme throughout the event (and the technologies being demonstrated) was the wisdom of Starrag’s strategy of ‘Engineering precisely what you value’ – with, effectively, Starrag taking a singular machine/technology development (or collective machines/technologies) to provide bespoke solutions to individual customers’ problems.

It was a theme that Starrag’s managing director, Bernhard Bringmann, highlighted: “We’re using a toolkit of technologies to help customers gain ever-higher process stability,” he said. “Adopting ‘built-in’ technologies such as temperature control sensors and collision protection systems, as well as achieving minimal ‘air cuts’ through adaptive roughing and the elimination of alignment problems, are just some examples of how Starrag is enabling customers to optimise machining routines, often gaining up to 50 per cent improvements in production output.

“Importantly, too, components are increasingly becoming more complex and require more demanding machining – even just a few years ago it would have been impossible to machine certain parts in a single, flow-line process – so we also work closely with customers to develop (and provide) special-purpose fixturing and tooling. Nowadays you need the whole package!”

Guest speakers Mauro Fioretti and Andrea Maurizio, president and chief of technology, respectively, of family-owned Pietro Rosa TBM, reinforced the message in their presentation ‘Strategic partnerships for innovation’.

The Italy-based aerospace group (with another division in North America) moved into the machining of forged blades in the 1980s and, said Mr Fioretti, “this is when our partnership with Starrag began”. Today, the company has six Starrag machines in its Italy plant and four in the USA (at New England Airfoil Products).

With annual revenues (in 2017) of $70 million, Pietro Rosa TBM includes jet engine aerofoils (compressor airfoils as well as variable, rotor, stator and turbine blades and discs) as well as steam turbines within its manufacturing focus and Mr Fioretti reflected how customers’ cost-down initiatives have spurred continuous improvement in production regimes – which is where the use of Starrag machining technologies comes to the fore.

“We’re selling flying hours not just engines,” added Mr Maurizio, “and, with engines operating at higher temperatures, there is an increasing need for compressor blades of titanium and nickel alloys. These super alloys are more difficult to machine, polish and test, so while we not only need the best five-axis milling machines, we also must have smart fixturing, high-level process automation and process monitoring, as well as a dependable supplier which is responsive and has superlative technical support.

“We need to automate as much as we can and include as many multiple processes as possible into flow lines. As aircraft programmes continue to grow with relatively low batch sizes gradually being replaced by stable, higher-volume quantities, it is clear that automation is the key to cost-competitiveness,” he affirmed.