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The structural characteristic of a hollow piston rod is that there is a hollow hole in the center of the piston rod, which is usually circular or hexagonal.
In internal combustion engines and compressors, the piston rod is a mechanical component that connects the piston and crankshaft, used to convert the reciprocating motion of the piston into the rotational motion of the crankshaft.
As the piston rod needs to rotate continuously with the reciprocating motion of the piston, opening a hollow hole in the center of the piston rod can reduce the weight of the piston rod, lower the friction between the piston rod and the crankshaft, and avoid premature wear of the piston rod. At the same time, adding lubricating oil inside the piston rod can enhance the lubrication effect and prolong the life of the piston rod.
Hollow piston rods are commonly used in internal combustion engines and compressors, especially in high-speed and high-power engines and compressors.
The application of hollow piston rods has become a trend in fields such as automotive engines, marine engines, and aircraft engines.
In addition, hollow piston rods are also used in some high demand mechanical equipment, such as high-speed trains, air compressors, injection molding machines, etc.