At the new GE Aviation manufacturing plant in Alabama, the mass production of highly sophisticated aviation components is well underway using additive manufacturing technology.
GE’s Auburn plant is running 28 metal additive manufacturing machines around the clock, producing fuel nozzle injectors (also called “nozzle tips”) for the best-selling LEAP jet engine from CFM International, a 50/50 joint company of GE and Safran Aircraft Engines of France.
It is the first sophisticated jet engine component to be produced using the additive manufacturing process, and it has been successfully operating in airline service since this summer as part of a growing LEAP jet engine fleet powering the Airbus A320neo aircraft.
Between GE Aviation’s Additive Technology Center in Cincinnati, Ohio, and the manufacturing site in Auburn, GE will produce about 6,000 LEAP fuel nozzle injectors in 2016, growing to 12,000 in 2017. In early 2017, all production of these components will occur in Auburn.
By 2020, GE is expected to operate more than 50 machines in Auburn, producing more than 35,000 engine fuel nozzle injectors annually using additive. By the end of the decade, GE is expected to have produced about 100,000 fuel nozzle injectors using additive.
The LEAP fuel nozzle injector is produced as a single structure. In contrast, producing the same part using conventional casting processes would require welding and brazing 20 different parts. Using the additive process, the LEAP nozzle injector is 25% lighter and five times more durable.
“The industrialization of our additive process is going very well,” said Sean Keith, manager of Machine Technology for GE Additive. “Our production rates and yields for the LEAP nozzle tips are where we had hoped, and cost curves are trending in the right direction.”
The Auburn plant is also among the sites being evaluated to produce fuel nozzle injectors for the new GE9X engine under development for the Boeing 777X. In addition, GE Aviation is evaluating locations for establishing additive manufacturing centers to produce components for GE’s new Advanced Turboprop Engine (ATP), which was launched by Cessna in 2015. About 35% of the entire ATP engine will be produced using additive. GE expects to run its first full ATP engine test by the end of 2017 in Europe.
One example of additive’s revolutionary impact on engineering design is GE Aviation’s Advanced Turboprop (ATP), which will power the new Cessna Denali single-engine turboprop aircraft. GE engineers were able to reduce 855 subtractive manufactured parts to 12 uniquely complex additive manufactured parts, which constitute 35% of the engine’s total architecture.
One of those 12 additive parts is the exhaust case, which serves as an aerodynamic flow pass allowing air to exit the engine with minimal pressure loss. The exhaust case must be designed with enough strength to withstand the pressure of the airflow travelling through the engine.
“If we had designed the ATP exhaust case using subtractive manufacturing techniques, we’d have to design the entire case with a thickness dictated by the weakest point, which adds unnecessary weight,” said Gordon Follin, GE’s engineering manager for the ATP program. “By utilizing additive, we designed significantly more complex aerodynamic shapes and then added features for structural stiffness. The ATP exhaust case has a very thin liner, which is the aerodynamic shape, and then we printed external spars on the case that provide the required stiffness. Additive gave us the flexibility to implement the strength where it’s needed, improve aerodynamics for markedly better performance and durability while lowering the weight of the system.”
Additive components reduce the ATP’s weight by 5% while contributing a 1% improvement in specific fuel consumption (SFC). The ATP is expected to improve time-on-wing by 33% compared to today’s most advanced turboprop engines.
“Additive provides GE engineers a whole new degree of creative freedom, fundamentally changing the way we approach design,” said Chris Schuppe, general manager of engineering for GE Additive. “The paradigm between the cost of manufacturing and the complexity of a design has been upended. With additive, designs are optimized for performance and productivity with a faster time between iterations.”
Another benefit of additive is the ability to print entire assemblies as opposed to building parts and then assembling those parts into a larger structure.
“Typically, the weakest element of an assembly is where parts come together because of factors like air leakages and wearing down of interface joints that bind the parts together. Additive eliminates leakage and wear paths because the interfaces are no longer required,” said Schuppe. “When we free an engineer’s mind from the constraints of how a part needs be designed so it can later be assembled, the engineer can activate the creative side of his or her brain to design parts that have never been built before.”
To expand additive to other design pursuits across the company, GE is leveraging its early successes on programs like the ATP to develop training courses to teach engineers how to design to the additive process.
“To optimize engineering designs to the additive process, engineers are being trained to study organic structures as they appear in nature,” said Schuppe. “We’re emulating ligaments, muscles and bones. For example, a bird’s bone structure is an effective model because it serves the functional purpose of flight but is also very light weight.”
GE is a leading end user and innovator in the additive manufacturing space. GE has invested approximately $1.5 billion in manufacturing and additive technologies at the GE Global Research Center, and has developed additive applications across six GE businesses, created new services applications across the company, and earned 346 patents in powder metals used for the additive process.
"We have invested years in proving out this technology for critical components in the heart of the engine," said Greg Morris, Strategy/Growth Leader for GE Additive. "Now we are well positioned to apply this technology to other components in the same harsh environment which could prove to be game changing for future engine programs and designs."
Now, GE is fully focused on becoming a leading supplier of additive machines, materials, and software for several industry segments, including aerospace, power generation, automotive, medical, and electronics with the launch of GE Additive, led by David Joyce, GE Vice Chairman and CEO of GE Aviation. GE engineers are utilizing the transformative power of additive manufacturing to revolutionize the company’s design practices for industrial products.
GE seeks to grow its new additive business to $1 billion by 2020. GE is planning to sell 10,000 additive machines over the next 10 years.
In addition to building out a portfolio of additive machines, GE anticipates that 25% of the advanced powder metal used in manufacturing will be in the additive manufacturing space. GE’s key efforts underway to position the company as an industry provider include:
- Concept Laser GmbH - In late October, GE reach agreement to acquire a 75% stake in Concept Laser for $599 million (€549 million). The agreement is structured to allow GE to take full ownership over several years. Concept Laser is a pioneer in the field, designing and manufacturing bed-based laser additive machines with customers in the aerospace, medical, dental, automotive, and jewelry industries. Headquartered in Lichtenfels, Germany, Concept Laser has operations in the United States (Grapevine, Texas), China, and a network of more than 35 distributors and agents. The deal is subject to regulatory approvals and expected to close this year.
- Arcam AB – On November 14, GE agreed to purchase controlling shares of Arcam AB of Sweden, following the conclusion of an extended public tender offer. Arcam shares tendered during the extended acceptance period – combined with Arcam shares acquired by GE – correspond to approximately 73.57% of the total number of outstanding shares for GE. Based in Mölndal, Sweden, Arcam AB is the inventor of electron beam melting machines for metal-based additive manufacturing, and a producer of advanced metal powders with customers in the aerospace and orthopedic industries. Arcam generated $80 million in revenues in 2015. Arcam also operates AP&C, a metal powders operation in Canada, and DiSanto Technology, a medical additive manufacturing firm in Connecticut in the U.S.A., as well as sales and application sites worldwide.
“These technologies will be bolstered by a growing global network of GE centers focused on additive research and technology,” said Mohammad Ehteshami, Vice President of GE Additive. “As GE develops its additive engineering and manufacturing capabilities, it further positions us to be better providers of the equipment.”