What is the function of the piston pin boss?

[StSienna]

Piston pins are used to connect the piston and connecting rod, transferring the force from the piston to the connecting rod or vice versa. Below is an introduction to piston pins: 1. Principle: Piston pins endure significant periodic impact loads under high-temperature conditions. Due to the limited swing angle of the piston pin within the pin hole, it is difficult to form a lubricating oil film, resulting in poor lubrication conditions. Therefore, piston pins must have sufficient rigidity, strength, and wear resistance. Their mass should be as small as possible, and there should be appropriate fit clearance and good surface quality between the pin and pin hole. Generally, the rigidity of the piston pin is particularly important. If the piston pin undergoes bending deformation, it may cause damage to the piston pin. 2. Quality requirements: The working conditions of piston pins involve high compression ratios, inability to form an oil film, and deformation incompatibility. Therefore, their design must ensure sufficient mechanical strength and wear resistance, along with high fatigue strength.