Laser textured discs improve marine engine performance

Friction discs laser-textured at Heriot-Watt University in Edinburgh, Scotland could reduce maintenance costs and downtime for the biggest ships sailing on the oceans.

German firm Man Energy Solutions tested the friction discs on its two-stroke engines on two ships sailing from Europe to Asia. The discs transfer power in engines and act as a safety device. They need to sustain a precise amount of friction: too much and the gear can be overloaded, too little and there could be premature slippage.

Currently, such discs are treated with a thermal spray coating to help them create friction. However, this method isn’t precise enough for industry.

Scientists from Heriot-Watt University in Edinburgh have therefore worked with Man Energy Solutions and Danish firm TRD Surfaces to develop a new laser-texturing process for the discs. The work was done as part of the EU-funded project SHARK, which aims to industrialise laser texturing.

Professor Duncan Hand from Heriot-Watt University said: 'Using lasers means we can create precise, uniform and replicable textures on the discs. 'We used laser pulses to experiment with different patterns, shapes, spacing and depths, with the aim of creating a new surface that would have a good grip on its counterpart.'

The high-friction concept was combined with a surface hardening process, carried out by TRD Surfaces. It effectively freezes the textured surface to ensure it doesn’t deform when it comes into contact with its counterpart. 

The team tested different texture spacings on the discs. (Credit: Heriot-Watt university)

The technique was tested extensively in the laboratory at Heriot-Watt and then on a specialist demonstrator. 

'We achieved a much higher and more reproducible friction coefficient than we had expected,’ said Hand. 'Improving the performance of the discs means significant savings on maintenance costs, which the shipping industry will welcome.' 

Jesper Vejlø Carstensen from Man Energy Solutions said: 'We needed a better solution for one of our high-friction components. After joining forces with Heriot-Watt and TRD Surfaces, we now have a precise, controllable and reproducible solution. As a vital add-on, we can perform non-destructive quality control of every part, and are installing the laser surface textured high friction discs in engines.’

MAN Energy Solutions has commercialised the innovation with TRD Surfaces as the supplier of the laser textured friction discs.