Piston Rings - PVD
Long Life – High Fuel Economy
Constant advances in combustion engines put increasing thermal and mechanical stress on components while its dimensions simultaneously decrease.
The resulting exacting demands have to be met with innovative technologies. The development led from simple cast iron rings via steel rings on to coatings which reduce wear and friction.
PVD stands for “physical vapour deposition”, a vacuum-based coating process where layers of hardening components are directly deposited onto the surface of the piston ring.
The PVD coatings are notable because of their high wear-resistance. This is achieved by a high hardness (1400-2200 Hv) and an extremely compact layer structure. A further advantage is the very smooth surface which results in considerable friction benefits.
Nowadays PVD rings are used successfully for numerous applications.
They are being used in commercial vehicles which have a required mileage of more than 1 million miles and modern highly stressed automobile diesel engines.
PVD technology is increasingly being used in conventional petrol engines. Its high wearresistance maintains the ring shape over a longer period of time.
For instance this allows a reduction of the ring tension of PVD coated oil control rings which in turn results in considerable friction benefits.
Based on the innovative PVD technology NPR of Europe can offer low friction and highly wear-resistant piston rings.
In this way NPR of Europe contributes greatly towards more economical and durable engines!
Piston rings - steel
Advantages and benefits
Why steel?
Today’s engines place higher demands on piston rings. Thermal and mechanical stress is increasing significantly. Additional restrictions on emissions are further demands on the precision of engine components.
All these factors have created the need for a material that must be stronger and harder than those previously used. Better sealing, resistance to fracture and wear under load are also required. Steel brings the suitable properties.
Different steel materials are used, depending on the requirements of the engine. Retrofitting during engine overhauls is possible at any time without any problems.
Steel ring vs. nodular cast iron ring
In newer engines, the lower axial ring height of steel rings allows them to be placed even closer to the piston crown, thus reducing exhaust emissions.
Advantages of steel rings
In the past, primarily alloyed gray iron or nodular iron was used as piston ring material in gasoline or diesel engines. Today, steel is being used more and more by engine designers. Steel rings have been used for over 30 years in the truck sector, e.g. at Mercedes-Benz.
The resulting good experience and technical progress in the processing of this material have contributed, among other things, to the widespread use of steel material in all areas of today’s engine technology.
- Reduction of oil consumption
- Lower exhaust emission
- Elongation strength
Piston rings – step land oil ring
Step Land with a worldwide patent protection
Unique design with a worldwide patent protection on the NE-Step Land oil wiper ring. The benefits are remarkable: up to 35% less friction, which is a further contribution to CO2 reduction in combustion engines.
Furthermore, oil consumption is reduced by up to 40%, and by more than 50% thanks to the optimized design of the oil passage surface.
This significantly reduces oil consumption in the upper speed range and thus ensures even cleaner combustion.
