Additive manufacturing of complicated sand cores for hydraulic rotary transmissions

Consolidation of 12 shot cores into one printed core improves core quality and gives many other benefits

Founded in 1887 as a Meier & Weichelt company, Georg Fischer in Leipzig, Germany, has been running a foundry that is home to Europe’s largest molding box for machine-molded iron castings since 1995. The foundry creates green sand molds fully automatically with the aid of pattern plates, which serve as negatives for the subsequent casting contour. Cores, shot in the cold box process, form the inner cavities of castings. Due to the high initial expenditures such as for models and core boxes as well as for the production of prototypes, the production process involved a lot of costs and time.

Usually, it can take months for foundries to produce a single prototype for presentation to the customer. It often causes significant delays until the final market launch. As times changed, the requirements for early delivery and complexity of such prototypes became more and more demanding, which could hardly be realized by conventional means.

 Discover in the case study: 

• Why the foundry decided to invest in ExOne's 3D sand printing technology 
• The foundry's new applications with 3D printing beyond rapid prototyping
• How the foundry consolidates 12 complicated shot cores for Hydraulic Rotary Transmission into one 3D-printed core
• The benefits that the foundry has got after leveraging sand 3D printing techology 
• Expansion of the foundry's manufacturing capabilities

“The core for the rotary transmission is an example of a very complicated core in our foundry. Conventionally produced, twelvepartial cores were needed to form the undercuts and thin channels. The assembly is time-consuming and error-prone. The 3D printer enables us to produce the cores in one piece only.” 

Eric Nierenberg,

Technologist of GF Casting Solutions Leipzig GmbH