PISTON RIK

Sell RIK Piston / Torak / Seher

The piston (also known as torak or seher) is located inside the cylinder liner and works with an up-and-down vertical motion. This movement functions to compress the mixture of diesel fuel and air entering the cylinder. The piston also serves as the receiver of combustion pressure and converts that pressure into energy to rotate the crankshaft via the connecting rod.

To ensure that the air–fuel mixture inside the cylinder is compressed properly, the gap between the piston and the cylinder liner wall must be tight, while still allowing enough clearance for material expansion due to combustion heat. This gap is called piston clearance, which generally ranges between 0.02mm–0.12mm. The variation depends on the level of expansion that can occur under combustion temperatures, which can reach up to 250°C. The tightness between the piston and the cylinder liner wall is further supported by the piston rings installed on the piston.

The piston is made from an alloy of aluminum and other metals (aluminum alloy) that must have the following characteristics:

• Lightweight, so that the piston can perform repetitive up-and-down motions easily, allowing the engine to achieve high RPM.

• Durable under pressure and combustion explosions produced by fuel–air ignition.

• Resistant to expansion caused by extreme heat inside the cylinder.

The piston is also equipped with a piston pin and circlip, which serve as connectors between the piston and the connecting rod through the bushing hole.