Fewer emissions and less friction, consumption and weight
ŠKODA AUTO has put into operation a new plasma coating line for its 1.0 TSI evo engines cylinders
technically innovative process that the PK – Component Production department has started using makes it possible to replace used cast iron cylinder liners by simply applying a powder layer with a total thickness of 0.15 millimetres. ŠKODA AUTO has invested almost EUR 29 million in this process, which will be used to produce the new three-cylinder engines of the EA211 evo model series. The new technology will reduce the friction, consumption, emissions and weight of the new-generation 1.0 TSI evo three-cylinder petrol engines. The plasma-coated motors will be built in Mladá Boleslav in three shifts and assembled as part of the FABIA, SCALA, OCTAVIA, KAMIQ, KAROQ models, as well as the OCTAVIA e-TEC models with mild-hybrid technology.
How the new technology works
During the production process, the engine block’s combustion chambers are first milled on the machining line. Next, the functional surfaces of the cylinders are roughened by a 1,500 W laser to enable perfect plasma adhesion. The laser beam then creates 10 grooves with an average depth of 40 micrometres (a micrometre is one one-thousandth of 1 millimetre) on a surface of 1 millimetre. The entire operation takes place in a protective nitrogen atmosphere to protect the laser optical devices from impurities and ensure the necessary degree of precision. A mixture of hydrogen and argon is used as the required plasma gas. Every minute, 4.5 litres of hydrogen run through the torch, and the resulting plasma reaches a temperature of up to 15,000°C. Powdered steel is fed into this, which contains aluminium, iron, carbon, silicon, manganese and other elements. The size of the individual grains of powder can be up to 50 micrometres. After application on the cylinder walls, the molten powder forms a layer about 250 micrometres thick, which is reduced to 150 by machining the rollers. Each cylinder undergoes quality control as part of the manufacturing process, during which the optical instruments first measure the roughened surface and then assess its condition after the application of the plasma. Subsequently, the structure of the plasma is examined by means of eddy currents. ED
Head of PK – Component Production
By applying the plasma, our motors’ efficiency is going to increase. The ultra-fine layer reduces friction losses and helps to reduce fuel consumption. In addition, this method distributes heat more evenly within the combustion chamber, thus improving the thermal stress on the engine.