Additive manufacturing revolutionizes design possibilities for GE engineers
BOSTON, Massachusetts – GE engineers are utilizing the transformative power of additive manufacturing to revolutionize the company’s design practices for industrial products.
Prior to the introduction of additive manufacturing, design creativity and complexity were dictated, and thus limited, by the production capability of a subtractive manufacturing machine. Those limitations led to design trades between critical factors such as performance, cost, durability and weight for products fielded in industries ranging from aerospace and power generation to medical and electronics.
Additive is the world’s first manufacturing method that allows engineers to simultaneously design improvements in product performance, reliability, cost and weight, all at faster speeds.
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 has invested approximately $1.5 billion in manufacturing and additive technologies at GE’s Global Research Center (GRC) in Niskayuna, New York, in addition to building a global additive network of centers focused on advancing the science.
Additive manufacturing is a key part of GE’s evolution into a digital industrial company and will leverage the Predix platform as part of GE’s Brilliant Factory initiative.
About GE Additive
GE Additive is part of GE (NYSE: GE), the world’s Digital Industrial Company, transforming industry with software-defined machines and solutions that are connected, responsive and predictive. GE is organized around a global exchange of knowledge, the "GE Store," through which each business shares and accesses the same technology, markets, structure and intellect. Visit GE Additive at www.ge.com/additive.
GE Additive is led by David Joyce, GE Vice Chairman and CEO of GE Aviation, an operating unit of GE and a world-leading provider of jet engines, components and integrated systems for commercial and military aircraft. For more information, visit us at www.geaviation.com.