Federal-Mogul upgrades galvanic piston ring coating

In rig tests, GDC60 – a galvanic coating with a higher and more evenly distributed nano-diamond content than the existing GDC50 product – reduced the friction coefficient up to 7 percent. First engine tests have shown the potential for wear reduction of up to 10 percent compared to GDC50 coatings, an improvement that will also prolong a better standard of oil distribution.

As cylinder pressures increase in modern two-stroke engines, greater scuff resistance is required – especially for the first compression ring.

“GDC60 will enable our customers to develop new, more efficient engines with higher cylinder pressures while staying with a familiar, well-proven ring coating technology,” commented Gian Maria Olivetti, chief technology officer, Federal-Mogul Powertrain.

Galvanic coatings are used for piston rings in around 90% of medium-speed engines and many low-speed engines, Peter Schmidt, head of application engineering, large bore engines, told guests at Federal-Mogul Powertrain’s technical day in Augsburg.

However, they are not used on MAN Diesel & Turbo’s cross-head piston rings as the engine developer prefers the self-lubricating and controlled wear effects of thermal sprayed coatings.

Federal-Mogul works with most if not all of the leading engine manufacturers and developers, providing a range of components from piston rings and cylinder liners to bearings and valve trains.