Auto Parts Engine Piston 3L 13101-54100 For TOYOTA

The whole piston can be divided into three parts: piston top, piston head and piston skirt.

The main role of the piston is to withstand the combustion pressure in the cylinder and transmit this force to the Crankshaft through the piston pin and connecting rod. In addition, the piston, together with the cylinder head and cylinder wall, forms the combustion chamber.

The piston head is the part above the piston pin seat, and the piston head is installed with a Piston Ring to prevent high temperature and high pressure gas from entering the crankcase and prevent oil from entering the combustion chamber; Most of the heat absorbed by the top of the piston is also transmitted to the cylinder through the piston head, and then transferred through the cooling medium.

All parts of the piston ring below the groove are called piston skirts. Its role is to guide the piston in the cylinder for reciprocating motion and withstand side pressure. When the engine is working, due to the effect of the gas pressure in the cylinder, the piston will bend and deform. After the piston is heated, the expansion amount is greater than that of other places due to the metal at the piston pin. In addition, the piston will produce extrusion deformation under the action of side pressure. As a result of the above deformation, the section of the piston skirt becomes an ellipse in the direction of the long axis perpendicular to the piston pin. In addition, due to the uneven distribution of temperature and mass along the axis of the piston, the thermal expansion of each section is large on the top and small on the bottom.