Housings and covers for railway axle boxes are usually produced using sand castings.

This process requires the production of complex tooling to produce the sand moulds and results in long lead times for customers.This is an expensive and complex process that most often results in long lead times for customers.

3D printing allows SKF to bring flexibility into this process by allowing the direct production of the sand moulds layer by layer without tooling. Using 3D printing is especially suitable for production of prototypes or rare spare parts where traditional tooling is not (yet) available.

To demonstrate the technology and to validate it for further commercial use, we have successfully collaborated on a customer project for a metro application: Two complete axle box prototypes (1 housing and 2 covers for each axle box) were developed. Using 3D printing enabled time savings of 6 weeks, bringing the production time down from 8 weeks to 2 weeks.

The parts meet all specifications in terms of material integrity, geometry, surface quality and other defined parameters, proving that there is no difference between an axlebox made from 3D printed sand molds or from traditional sand casting.