When Caterpillar began its current investment in 3D-printing components for heavy equipment earlier this decade, the company’s engineers and chemists tried to manage their expectations. But after only a few years of tinkering with commercially available additive-manufacturing technology, the equipment manufacturer already has introduced 3D-printed components into its supply chain, with little fanfare or advertisement.

“We’re at the point now where we actually have parts in production that are being 3D-printed,” says Stacey Delvecchio, additive-manufacturing product manager at Caterpillar. “We have less than 100 parts’ SKUs, so it’s not like we conquered the world. But the fact that we actually have parts in production that are 3D-printed is a big accomplishment.”

The parts being produced today are primarily intended for the aftermarket, such as dealer repairs and replacements. For example, a grommet for a mounting on a motor grader is 3D-printed from elastopolymer, saving money on a low-volume part. While not all the parts are critical, Cat found that it was no longer economically viable to retool their traditional manufacturing pipelines to produce these highly specialized components.

At the moment, only one part in new Cat machines is solely produced via 3D printing. Gas turbines made by Caterpillar’s Solar Turbine subsidiary require fuel mixers with complex fin designs that are difficult to cast with traditional methods, so Devecchio’s team found it easier to 3D-print the mixers using a particle-bed-and-sintering technique. In this type of 3D printing, metal powder is heated and fused into place by a computer-controlled laser following a path prescribed by a 3D model. Successive layers of powder are added until the piece is complete. The resulting fuel mixer (left) has all the complex crevices the design called for and only had to be removed from the base plate after the sintering was complete.

While she often gets asked by other Cat employees about 3D-printed parts, Devecchio maintains it’s no longer a special case. “We’re doing it now. The quality is good enough we can put it on Cat products,” she says.

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