How To Better Choose The Cylinder Barrel Material
As we all know, cylinder barrel as the main component of the hydraulic cylinder, the material and processing quality will directly affect the life and reliability of the whole custom hydraulic cylinder. In the selection of hydraulic cylinder materials, for the cylinder, it is necessary to pay attention to the pressure performance, and the strength and hardness should be up to standard. In addition, it should be able to withstand a certain working pressure for a long time without deformation and bending.
Hydraulic cylinder barrel is the main body of the hydraulic cylinder, to withstand a lot of liquid pressure, therefore, there should be enough strength and hardness. The cylinder bore and the cylinder head and the sealing system device constitute the sealing working volume of a hydraulic cylinder, so the cylinder should have reliable sealing. Many times, it is necessary to weld oil ports, flanges and other components on the cylinder of the hydraulic cylinder, which requires the material of the cylinder to have good welding performance. The inside diameter of the tube usually does not require paint or chromium protection, as the hydraulic oil protects it from corrosion.
The cylinder of the hydraulic cylinder is generally made of seamless steel tube, which is a kind of high-precision steel pipe material after cold drawing or hot rolling. It has the advantages of no oxide layer on the inner and outer walls, no leakage under high pressure, high precision, high finish, cold bending without deformation, flaring, flattening without cracks, etc.
The chemical composition of the cylinder steel tube is carbon C, silicon Si, manganese Mn, sulfur S, phosphorus P, chromium Cr, according to the carbon content can be divided into low carbon steel, medium carbon steel and high carbon steel. The carbon content of low carbon steel is generally less than 0.25%, the carbon content of medium carbon steel is generally between 0.25 and 0.60%, and the carbon content of high carbon steel is generally greater than 0.60%.
Hydraulic cylinder commonly used materials are mainly:
20# steel pipe: 20 refers to the carbon content of 0.2%, belongs to low carbon steel, the steel strength is low, toughness, plasticity and weldability are good.
35# steel pipe: The average carbon content is about 0.35%, which is medium carbon steel.
45# steel pipe: the carbon content is about 0.45%, which is medium carbon steel.
The material of the hydraulic cylinder can be selected according to the pressure of the working medium: 20# steel pipe can be used for low pressure cylinder, and 45# steel pipe can be used for high pressure cylinder.
According to the working condition selection: In the working temperature of the hydraulic cylinder below -50 ° C, 35# steel pipe or 45# steel pipe must be used, and it must be conditioned.
Whether you need to weld: If you need to weld the cylinder with the cylinder head or flange, you can choose 20# steel pipe and 35# steel pipe, and then adjust the quality after mechanical pre-processing, because their welding performance is better. Cylinder not welded with other parts, use tempered 45# steel pipe.