Surface roughness refers to the small spacing and small peak-to-valley unevenness on the surface of the processed seamless steel pipe. Tool marks during processing, plastic deformation during cutting separation, friction between the tool and the machined surface, and high-frequency vibration of the process system are all causes of surface roughness. The surface roughness will affect the wear resistance of the parts, the stability of the matching properties, the fatigue strength of the parts, the corrosion resistance of the parts, and the sealing of the parts.
The main reasons for the surface roughness of seamless steel pipes are:
1) Tool marks during processing;
2) Plastic deformation during cutting and separation;
3) The friction between the tool and the machined surface;
4) High-frequency vibration of the process system.
The surface roughness of seamless steel pipe is mainly manifested in the following aspects:
1) Surface roughness affects the wear resistance of seamless steel pipes. The rougher the surface, the smaller the effective contact area between the mating surfaces, the greater the pressure, and the faster the wear.
2) Surface roughness affects the stability of fit properties. For clearance fit, the rougher the surface, the easier it is to wear, so that the clearance gradually increases during the working process. For interference fit, since the microscopic convex peaks are squeezed flat during assembly, the actual effective interference is reduced and the connection strength is reduced.
3) Surface roughness affects the fatigue strength of seamless steel pipes. There are large troughs on the surface of rough parts, which are sensitive to stress concentration like sharp notches and cracks, thus affecting the fatigue strength of parts.
4) Surface roughness affects the corrosion resistance of seamless steel pipes. Rough surface can easily cause corrosive gas or liquid to penetrate into the inner layer of the metal through the microscopic valleys on the surface, causing surface corrosion.
5) Surface roughness affects the tightness of seamless steel pipes. Rough surfaces cannot fit tightly, and gas or liquid leaks through the gaps between the contact surfaces.
6) Surface roughness affects the contact stiffness of seamless steel pipes. Contact stiffness is the ability of the joint surface of parts to resist contact deformation under the action of external force. The stiffness of a machine is largely determined by the stiffness of the contact between the parts.
7) Affect the measurement accuracy of seamless steel pipes. The surface roughness of the measured surface of the seamless steel pipe and the measuring surface of the measuring tool will directly affect the accuracy of the measurement, especially in precision measurement.
The main reasons for the surface roughness of seamless steel pipes are:
1) Tool marks during processing;
2) Plastic deformation during cutting and separation;
3) The friction between the tool and the machined surface;
4) High-frequency vibration of the process system.
The surface roughness of seamless steel pipe is mainly manifested in the following aspects:
1) Surface roughness affects the wear resistance of seamless steel pipes. The rougher the surface, the smaller the effective contact area between the mating surfaces, the greater the pressure, and the faster the wear.
2) Surface roughness affects the stability of fit properties. For clearance fit, the rougher the surface, the easier it is to wear, so that the clearance gradually increases during the working process. For interference fit, since the microscopic convex peaks are squeezed flat during assembly, the actual effective interference is reduced and the connection strength is reduced.
3) Surface roughness affects the fatigue strength of seamless steel pipes. There are large troughs on the surface of rough parts, which are sensitive to stress concentration like sharp notches and cracks, thus affecting the fatigue strength of parts.
4) Surface roughness affects the corrosion resistance of seamless steel pipes. Rough surface can easily cause corrosive gas or liquid to penetrate into the inner layer of the metal through the microscopic valleys on the surface, causing surface corrosion.
5) Surface roughness affects the tightness of seamless steel pipes. Rough surfaces cannot fit tightly, and gas or liquid leaks through the gaps between the contact surfaces.
6) Surface roughness affects the contact stiffness of seamless steel pipes. Contact stiffness is the ability of the joint surface of parts to resist contact deformation under the action of external force. The stiffness of a machine is largely determined by the stiffness of the contact between the parts.
7) Affect the measurement accuracy of seamless steel pipes. The surface roughness of the measured surface of the seamless steel pipe and the measuring surface of the measuring tool will directly affect the accuracy of the measurement, especially in precision measurement.
