French truck maker Renault has produced a pioneering prototype 3D-printed engine.
A team of engineers and designers at the Renault Trucks Lyon Powertrain Engineering Department focused on using metal additive manufacturing – metal 3D printing – as a future engine manufacturing process, creating a prototype DTI 5 4- cylinder Euro-6 step C engine designed exclusively by 3D printer.
Although the complete engine was already designed virtually, rocker arms and camshaft bearing caps were manufactured by metal 3D printing and successfully bench-tested for 600 hours inside a Euro-6 engine.
“The aim of this project is to demonstrate the positive impact of metal additive manufacturing on the size and weight of an engine,” explained Damien Lemasson, Project Manager at Renault Trucks. “This process has enabled us to reduce the weight of a four cylinder engine by 120 kg or 25%. The tests we have carried out prove the durability of engine components made using 3D printing. It’s not just cosmetic.”
Metal additive manufacturing opens up new development opportunities for engines. It works by adding materials layer after layer and can be used to create complex organic forms, as well as optimising the sizing of parts and reducing the number of assembly operations and therefore the number of components in an engine.
“Additive manufacturing releases us from constraints and unlocks the creativity of engineers,” explained Lemasson. “The procedure is a source of disruptive technology for the engines of tomorrow, which will be lighter and more functional, thereby offering optimal performance.”
The number of components in the DTI 5 engine has been reduced by 25%, making a total of 200 fewer parts.
For haulage companies, metal 3D printing carries a number of advantages. They will be able to optimise the overall operating costs of their fleet of vehicles, since a reduction in engine volume will lead to greater payloads and lower fuel consumption.
In the short-term, this manufacturing procedure can be used for highly specific applications or small runs, but Renault’s engineers are looking to deploy the technique into mass manufacturing.