Machining Method of Hydraulic Cylinder Tubing
Hydraulic cylinder tube is a high-precision steel tube that has been cold drawn or processed through Drawn Over Mandrel for welding. The seamless material has no oxide layer on its inner and outer diameter, making it able to withstand high pressure without any leakage. It has a high level of precision and finish, and does not deform during cold bending or crack during flaring and flattening. As a result, it is primarily used to produce components for pneumatic or hydraulic systems, such as pneumatic cylinders or hydraulic cylinder barrels.
The chemical composition of the honed cylinder tubing contains Iron, carbon, silicon, manganese, sulfur, phosphorus and chromium.
The method of Skiving & Roller burnishing (SRB) is usually used for hydraulic cylinder barrels.
- SRB helps improve the surface’s corrosion resistance and fatigue strength, as well as enhance the wear resistance and reduce surface roughness through cold work hardening.
- Roller burnishing is a chipless processing that changes the surface structure, mechanical properties, shape, and size through plastic deformation of metal at room temperature.
- SRB is a method that combines finishing and strengthening in one process, unlike grinding.
- Rolling is a pressure finishing processing that uses the cold plasticity of metal at room temperature to reduce roughness and improve hardness and strength.
- Rolling forms a dense fibrous structure and residual stress layer, improving the wear and corrosion resistance of the surface while improving compatibility.
- Rolling is a plastic working method without cutting.
Advantages of Hydraulic Cylinder Tubes:
- Surface roughness improvement with roughness value reaching Ra≤0.04 μm
- Correct roundness with an ellipticity of ≤0.01 mm
- Increased surface hardness and elimination of stress and deformation
- Presence of residual stress layer after processing, resulting in a 30% increase in fatigue strength
- Improved matching quality, reduction in wear, and longer service life of parts, with lower processing cost.