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Do You Want to Master Connecting Rod Knowledge?

I believe that when you browse our blog, you want to know about connecting rods. Of course, it is also possible that you want to buy connecting rods. Today’s blog will introduce what a connecting rod is and some basic knowledge about connecting rods.

Next, LANDTOPMALL will explain the knowledge of connecting rods.

Connecting Rod

What is Connecting Rod

The connecting rod connects the piston and the crankshaft, and transmits the force on the piston to the crankshaft, converting the reciprocating motion of the piston into the rotational motion of the crankshaft.

Introduction of Connecting Rod

The connecting rod group is composed of connecting rod body, connecting rod big end cap, connecting rod small end bushing, connecting rod big end bearing bush, and connecting rod bolts (or screws).

The connecting rod group is subjected to the gas force from the piston pin, its own swing, and the reciprocating inertial force of the piston group. The magnitude and direction of these forces are periodically changed. Therefore, the connecting rod is subjected to alternating loads such as compression and tension.

The connecting rod must have sufficient fatigue strength and structural rigidity. Insufficient fatigue strength will often cause the connecting rod body or connecting rod bolt to break, resulting in a major accident of damage to the whole machine. If the stiffness is insufficient, it will cause bending deformation of the rod body and out-of-round deformation of the big end of the connecting rod, resulting in eccentric wear of the piston, cylinder, bearing, and crank pin.

Connecting Rod

The Structure of the Connecting Rod

The connecting rod body consists of three parts, the part connected with the piston pin is called the small end of the connecting rod; the part connected with the crankshaft is called the big end of the connecting rod, and the part connecting the small end and the big end is called the connecting rod body.

The small end of the connecting rod is mostly a thin-walled annular structure. In order to reduce the wear between the connecting rod and the piston pin, a thin-walled bronze bushing is pressed into the small end hole. Drill holes or grooves in the small head and bushing to allow splashing oil to enter the mating surfaces of the lubricating bushing and piston pin.

The connecting rod shaft is a long rod, which is also subjected to large forces during work. In order to prevent it from bending and deforming, the rod body must have sufficient rigidity. For this reason, most of the connecting rod shafts of vehicle engines adopt an I-shaped section, which can minimize the mass under the condition of sufficient rigidity and strength, and an H-shaped section is used for high-strengthened engines. Some engines use the small end of the connecting rod to spray oil to cool the piston, and a through-hole must be drilled in the longitudinal direction of the rod body. In order to avoid stress concentration, the connection between the connecting rod body and the small end and the large end adopts a smooth transition of a large arc.

In order to reduce the vibration of the engine, the quality difference of each cylinder connecting rod must be limited to the minimum range. When assembling the engine in the factory, it is generally grouped according to the mass of the large and small ends of the connecting rod in grams. Group connecting rod.

On the V-type engine, the corresponding cylinders of the left and right rows share a crankpin, and the connecting rods have three types: parallel connecting rods, fork connecting rods, and main and auxiliary connecting rods.

That’s it for today’s introduction to the connecting rod. I believe you already have a specific image of the connecting rod. If you still want to learn more about connecting rods, or others, or want to buy parts such as connecting rods. You can visit LANDTOPMALL and you will have unexpected surprises.


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