Piston rod commonly used material and selection

Piston rod commonly used material and selection （活塞杆常用材质及选型）

The piston rod is a moving part with frequent movement and high technical requirements, and is one of the main key parts of the hydraulic cylinder.

Commonly used piston rod material

Piston rod is a kind of shaft parts, it is relatively slender, its long diameter is relatively large, its main use of the following materials：

1.45# Steel ( C45 , SAE1045 ) material
45# steel is a high-quality carbon structure steel, the hardness is not high and easy to cut, after quenching, its surface hardness can reach 45-52HRC. And it can also have better cutting performance and higher strength, toughness and other comprehensive mechanical properties, so it is one of the commonly used materials for shaft parts.

Usually for shock absorber we use 45# material .

2.40Cr steel
40Cr steel is also a more commonly used material in the production of piston rods, it is not only a medium carbon tempered steel, but also a cold heading die steel. It has good comprehensive mechanical properties and is generally suitable for the manufacturing of shaft parts with medium precision and high speed.

3.Stainless Steel
Stainless steel has the characteristics of resistance to air, steam, water and other weak corrosive media, commonly used 304, 316, 402 these materials. theseThe weldability, polishing, heat resistance, corrosion resistance, corrosion resistance are relatively good, through precision cold drawing, fine grinding, high precisionDegree polishing and other processes, the technical indicators of the piston rod manufactured by it are in line with and exceed national standards, so it is often used in hydraulic cylinders.

Piston rod material selection

1.The piston rod of the hydraulic cylinder is usually made of 45# steel, which is tempered and treated with chromium plating 0.03~0.05mm thick after surface turning and grinding.Typical chrome-plated piston rods use 45 # steel, a material that is easy to process and weld with high strength and wear resistance. You can expect tensile strength in excess of 80,000 psi, and may also expect chromium 0.0005 inches (1/2 thou) thick to further increase surface hardness and reduce the likelihood of corrosion.

2.When there is a large impact force and heavy load transmission, in order to make the piston rod have enough working strength, 40Cr steel can be selected.

3.In some special areas, due to the impact of environmental factors, the equipment needs to have corrosion resistance and other requirements. Stainless steel piston rod has corrosion resistance, acid resistance properties, but also can help improve fatigue strength, long-term use will not cause wear parts, so it is especially suitable for use in some high-strength large equipment.

4.The piston rod is generally designed as a cylinder, and hollow piston rod can be used if the diameter is larger.
The piston rod has two kinds of solid rod and hollow rod, the solid piston rod material is 35#, 45# steel, and the hollow piston rod material is 35#, 45# seamless steel pipe.