The piston connecting rod set consists of pistons, piston rings, piston pins, connecting rods and connecting rod shingles.
The piston connecting rod set changes the reciprocating motion of the piston into the rotary motion of the crankshaft, and at the same time transforms the force acting on the piston into the external output torque of the crankshaft to drive the wheels of the car. It is the transmission of the engine, which transmits the pressure of the combustion gases to the crankshaft to make the crankshaft rotate and output power.
Connecting rod body is a long rod, in the work of the force is also larger, in order to prevent its bending deformation, the rod body must have enough stiffness. For this reason, most of the connecting rod body of the automotive engine Ⅰ section.
Some engines use connecting rod small head injection oil cooling piston, must be drilled in the longitudinal through hole in the rod body. In order to avoid stress concentration, connecting rod body and small head, big head connection are used in large arc smooth transition.
In order to reduce the vibration of the engine, the quality of the connecting rod must be limited to the minimum range of each cylinder, in the factory assembly of the engine, are generally measured in grams of connecting rods according to the quality of the large and small head grouped together, the same engine with the same group of connecting rods.
Expanded Information: Piston rings are subject to high temperature and high pressure of the gas in the cylinder when they are at work, their temperature is high and they move at high speeds in the cylinder, coupled with high-temperature deterioration of the oil and deterioration of lubrication conditions, and their wear and tear is serious. Piston ring wear failure, the engine startup difficulties, power, crankcase pressure, oil loss, exhaust smoke, piston side area carbon is serious. Because of the unevenness of the cylinder wear, so that it becomes taper and ellipticity, the piston reciprocating movement in which, along the neck to produce a one-shrinking movement, so that the ring is subjected to bending stress and easy to break, resulting in the engine stuck, pulling the cylinder, the engine does not work. Piston rings are generally cast in alloy cast iron. The working surface of the first gas ring is generally plated with porous chromium. (Porous chromium has high hardness and can store a small amount of oil), the other generally plated with tin or phosphatized to improve break-in performance.