ARTICULATED PISTON
One of the two parts in this type of pistons is called the top (steel) and the other is called the skirt and it is produced separately from different materials. The steel part of the assembled pistons is usually made of forged steel or cast steel. This part is also steel, which provides a more uniform cooling in the piston dome. The skirt is, if not always, made of mostly aluminum material.
Higher engine output per liter and improvements in engine efficiency required higher pressure and temperature in the low fuel and low pollutant emission combustion chamber.
This greatly affected the piston design. Two-piece piston design has been designed especially in high mechanical and thermal stresses. These pistons are designed for pressures exceeding 200 bars and road distances exceeding 1 million kilometers. Steel piston guarantees minimum wear. The reduced clearance of the upper area with steel rings ensures consistently low oil consumption.
The piston steel part is usually made of forged steel or cast iron, which both materials show high strength in the high temperature and pressure environment released during combustion.
Longer service time; the main reason for this is the promisingly great engine life and the forged steel is much more durable than aluminum.
Reduce piston stroke; this reduces both noise and wear, but also shows higher performance in the cold engine starting temperature phase.
Tougher top section; while aluminum alloys are insufficient in the face of increased pressure and temperature in high efficiency low emission diesel engines, steel parts exhibit high strength and toughness.
In addition, the increased piston weight and the increase in the load on the power organs can be said as disadvantage.