Improve the surface roughness, and the roughness can basically reach Ra≤0.08μm . Correct the roundness, the ellipticity can be ≤0.01mm . Improve the 16Mn Hydraulic Cylinder Tube surface hardness, eliminate the stress deformation, and increase the hardness by HV≥4° ; there is a residual stress layer after processing , which increases the fatigue strength by 30% . Improve the quality of the fit, reduce wear and extend the service life of the parts, but the processing cost of the parts is reduced. 1. The main feature of seamless steel pipe is that it has no welded seam and can withstand greater pressure. The product can be rough cast or cold drawn parts. 2. The cylinder tube is a product that has appeared in recent years, mainly because the inner hole and outer wall dimensions have strict tolerances and roughness.