Pratt & Whitney, a United Technologies Corp. (NYSE: UTX) company, has developed and applied a suite of innovative materials technologies that are optimized to improve fuel burn, reduce weight and increase component durability for its PurePower® Geared Turbofan™ (GTF) engine family. The first PurePower production engines are scheduled to be delivered to customers later this year.
In the geared turbofan architecture, a reduction gearbox between the fan and the low pressure shaft allows the latter to run at a higher rotational speed that enables fewer stages to be used in both the low pressure turbine and compressor (LPT and LPC). The suite of technologies working together allows the company's latest engine family to be a game changer, according to Frank Preli, chief engineer, materials and processes, Pratt & Whitney.
"Pratt & Whitney pioneered multiple technologies that, along with the geared architecture of the GTF engine, deliver incredible performance improvements," said Preli. "We have been driving innovation with materials for decades and have tailored the materials' properties to provide significant customer benefits today."
Among the advanced material technologies that enable the superior performance of the GTF are:
Hybrid Metallic Fan Blades: The Pratt & Whitney low-speed fan allows the use of a very lightweight and low-cost aluminum-lithium alloy material for the blade. The company has developed new fan blade designs and materials processing technologies that meet all safety and certification requirements while providing world-class aerodynamic efficiency levels compared with any other fan in service including composite blades of the same size class.
Next Generation Powder Metal Disk Technology: Pratt & Whitney pioneered the development and production of powder metal nickel-based superalloys. These disks are critical components that operate at high stresses and temperatures. In addition to developing the alloys, the company developed the powder-making process and a specialized process, isothermal forging, to manufacture these components. The technology is currently in its fourth generation of materials development, which includes processing steps to tailor the mechanical capabilities to specific zones within the part.
Next Generation Single Crystal Alloys and Thermal Barrier Coatings: The combination of advanced alloys and single crystal casting processes, coupled with oxidation coatings and thermal barrier coatings (TBC), enables Pratt & Whitney turbine blades to operate at temperatures that are hundreds of degrees above the melting point of the base material. The company has developed high-temperature alloys and casting processes that allow highly effective cooling passages, enabling both high temperature operation and lower cooling air flow. In addition, cathodic arc oxidation resistant coatings and TBCs applied using electron beam or plasma technology ensure maximum engine durability.
Titanium Aluminide: These materials enable higher temperature operation than traditional titanium alloys and are lighter than the nickel alloys they replace. For the GTF engine, Pratt & Whitney has worked with MTU Aero Engines, based in Germany, to develop a wrought form of these alloys for high-speed LPT blades, which have two times the strength of the more conventional cast alloys in use across the industry.
"Our highly engineered suite of technologies function as a system that differentiates performance and maximizes customer value," said Tom Prete, vice president, Engineering. "Our PurePower engines are meeting the commitments we made to customers, as demonstrated in 16,000 hours of engine testing. They will provide world-class performance while in service and extended time on wing between overhauls."
Pratt & Whitney is a world leader in the design, manufacture and service of aircraft engines and auxiliary power units. United Technologies Corporation, based in Hartford, Connecticut, provides high technology products and services to the building and aerospace industries. To learn more about UTC, visit www.utc.com or follow the company on Twitter: @UTC.
This press release contains forward-looking statements concerning the anticipated performance of new products and anticipated future business opportunities. Actual results may differ materially from those projected as a result of certain risks and uncertainties, including but not limited to changes in levels of demand in the aerospace industry, in levels of air travel, and in the number of aircraft to be built; challenges in the design, development, production and support of advanced technologies; as well as other risks and uncertainties, including but not limited to those detailed from time to time in United Technologies Corp.'s Securities and Exchange Commission filings.