Pipe surface roughness is the machining surface having a smaller pitch and the tiny valley irregularities. The distance between two peaks or two troughs (the pitch) is small (less than 1mm), it is difficult to distinguish with the naked eye, so it belongs to the microstructure geometry errors. Surface roughness is, the more smooth the surface. The surface roughness of size, have a great impact on the performance of mechanical parts.
Pipe surface roughness mainly in the following aspects:
1) Pipe surface roughness of the parts wear resistance. The rougher the surface, the smaller the effective contact area between the mating surfaces, the greater the pressure, the faster the wear.
2) Pipe surface roughness of stability of the complex nature. For clearance fit, the rougher the surface, the more easy to wear, so that the gap increases during operation; interference fit, because the assembly will squeeze microscopic convex peak level, reducing the actual effective interference, reduce the coupling strength.
3) Pipe surface roughness of fatigue strength of parts. There is a big part of the surface roughness of the trough, they are like sharp corners, as gaps and cracks, is very sensitive to stress concentration, thus affecting the fatigue strength of parts.
4) Pipe surface roughness of parts corrosion resistance. Rough surface, easy to make corrosive gas or liquid to penetrate through the surface of microscopic metal inner valley, causing surface erosion.
5) Pipe surface roughness of the parts of the seal. Unable tight fit between the rough surface, gas or liquid leakage gap between the contact surfaces through.
6) Contact stiffness and surface roughness of the parts. Part bonding surface contact stiffness is in the external force, the contact resistance to deformation. Rigidity of the machine depends largely on the contact stiffness between the various parts.
7) Affect the measurement accuracy of parts. Part measured surface and measuring tool to measure the surface roughness of the surface will directly affect the accuracy of measurement, especially in precision measurement. Further, the surface roughness of the parts plated coatings, thermal conductivity and contact resistance, reflectivity and radiation performance, liquid and gas flow resistance, the flow of current in the conductor surface so there will be different degrees of impact.
