Piston Connecting Rod Set

The piston connecting rod group converts the reciprocating motion of the piston into the rotational motion of the Piston Connecting Rod Set.
Piston connecting rod group consists of piston, piston ring, piston pin, connecting rod, connecting rod bearing bush, etc.

Piston

The function of the piston is to withstand gas pressure and drive the crankshaft to rotate through the piston pin and connecting rod.
According to the different functions of each part of the piston, the piston can be divided into three parts: the top of the piston, the head of the piston and the skirt of the piston

1) Piston top
The top of the piston is an integral part of the combustion chamber, which is mainly used to withstand gas pressure. Its shape and size are related to the form of the combustion chamber, and are all to meet the requirements of the formation and combustion of the combustible mixture. The top shape of the piston can be divided into four types, namely flat top, convex top, concave top and pit.

2) Piston head
Piston head refers to the part between the first piston ring groove and the piston pin hole. The head generally has several ring grooves to install the piston ring that acts as a seal, so the head is also called the leak-proof part. Diesel engines have a high compression ratio. Generally, there are four ring grooves. The upper three are installed with gas rings, and the bottom one is installed with oil rings.

3) Piston skirt
The piston skirt refers to the part from the lower end face of the oil ring groove to the lowermost end of the piston, which includes the pin seat hole for the piston pin. The piston skirt guides the reciprocating motion of the piston in the cylinder and is subjected to side pressure.

Piston ring

The function of the air ring is to ensure the tightness between the cylinder and the piston, prevent air leakage, and transfer most of the heat absorbed by the top of the piston to the cylinder wall, which is taken away by the cooling water.
The oil ring plays the role of oil distribution and oil scraping. When the oil ring goes down, scrape off the excess oil on the cylinder wall, and apply it on the cylinder wall when it goes up.
A uniform oil film, which can not only prevent the oil from channeling into the cylinder and burn out, but also reduce the frictional resistance between the piston, the piston ring and the farm road. In addition, the oil ring can also play an auxiliary role in sealing gas.

Piston pin

The function of the piston pin is to connect the piston and the small end of the connecting rod, and transmit the gas pressure on the piston to the connecting rod.
There are two ways to connect the piston pin with the piston pin seat hole and the connecting rod small end bushing hole, namely full floating and semi-floating.

Connecting rod

The function of the connecting rod is to connect the piston and the crankshaft, and to transmit the gas pressure on the piston to the crankshaft;becomes the rotational motion of the crankshaft. The small end of the connecting rod is connected with the piston through the piston pin, and the large end of the connecting rod is connected with the connecting rod journal of the crankshaft.
In order to reduce the frictional resistance and the wear of the crankshaft connecting rod journal, a tile-type sliding bearing is installed in the big end hole of the connecting rod, referred to as the connecting rod bearing. The inner surface is cast with a wear-resistant alloy layer and the back has a high finish.