What do RA, RZ, RP, RQ, and RSM represent in the roughness parameters


Release time:

2024-01-31

Surface roughness refers to the unevenness of the machined surface with small spacing and small peaks and valleys. The distance (wave distance) between its two peaks or valleys is very small (below 1mm), which belongs to the micro geometric shape error. The smaller the surface roughness, the smoother the surface. Surface roughness is generally formed by the machining method used and other factors, such as friction between the tool and the surface of the part during the machining process, plastic deformation of the surface layer metal during chip separation, and high-frequency vibration in the process system. Due to differences in processing methods and workpiece materials, there are differences in the depth, density, shape, and texture of the marks left on the processed surface. Surface roughness is closely related to the fitting properties, wear resistance, fatigue strength, contact stiffness, vibration, and noise of mechanical parts, and has a significant impact on the service life and reliability of mechanical products. Generally, Ra is used for annotation.

What do RA, RZ, RP, RQ, and RSM represent in the roughness parameters

Surface roughness refers to the unevenness of the machined surface with small spacing and small peaks and valleys. The distance (wave distance) between its two peaks or valleys is very small (below 1mm), which belongs to the micro geometric shape error. The smaller the surface roughness, the smoother the surface.
Surface roughness is generally formed by the machining method used and other factors, such as friction between the tool and the surface of the part during the machining process, plastic deformation of the surface layer metal during chip separation, and high-frequency vibration in the process system. Due to differences in processing methods and workpiece materials, there are differences in the depth, density, shape, and texture of the marks left on the processed surface.
Surface roughness is closely related to the fitting properties, wear resistance, fatigue strength, contact stiffness, vibration, and noise of mechanical parts, and has a significant impact on the service life and reliability of mechanical products. Generally, Ra is used for annotation.
1. RA: represents the arithmetic mean deviation of the contour.
The arithmetic mean of the absolute distance between a point on the contour line along the measurement direction (Y direction) and the reference line within the sampling length.
2. RZ: represents the ten point height of micro unevenness.
It refers to the sum of the average height of 5 ****** contour peaks and the average depth of 5 ******* contour valleys within the sampling length.
3. Rp: represents the peak height of ****** contour waves.
The distance between the top line of the highest peak and the bottom line of the lowest valley of *****'s contour within the sampling length.
4. Rq: represents root mean square roughness.
5. RSM: represents the average width of contour units.
The average distance between micro unevenness of the contour within the sampling length