Техническая информация Sumitomo - страница 31

■ Finished Surface Roughness

• Types and Definitions of Typical Surface Roughness
• Relationship with Triangular Symbols

Types Symbol Method of Determination Descriptive Figure Designated Designated Standard

Designated *

This is the value expressed in micrometers Values for Values for Reference Triangular

Values for

(μm), obtained by extracting from the roughness *1) *2) Length Values, Symbols

Ra

curve a segment of the reference length in the Rz RzJIS (mm)

direction of the mean line and measuring the

distance from the d eepest valley to the highest (0.05) (0.012) (0.05)

m peak of the extracted segment in the direction of

*1) 0.1 0.025 0.1

the longitudinal magnification of that roughness Rz JJJJ

curve. L 0.2 0.05 0.2

0.25 Remarks: When obtaining Rz, care must be taken

Rz = Rp + Rv 0.4 0.10 0.4

to extract a segment of the reference length from a portion having no

unusually high peaks and deep valleys 0.8 0.20 0.8

as they are considered as flaws.

1.6 0.40 1.6

This is the value expressed in JJJ

curve a segment of the m reference length in the direction 12.5 12.5

Ra of the mean line, plotting a 3.2 JJ

and the Y-axis set in the direction Ra=ࠈ 㹰I[㹲G[ L of the extracted segment, and 0

This is the value expressed in 8

(70) 25 (70)

micrometers (μm), obtained by

extracting from the roughness curve 100 100

a segment of the reference length in the direction of the mean line, m (140) (140) measuring the heights of the highest to

*2) 200 200

Rz 5th highest peaks (Yp) as well as the L

JIS (50)

heights of the deepest to 5th deepest (280) (280) — —

valleys (Yv) in the direction of the (100)

Rz = (Yp 1+Yp2+Yp3+Yp4 +Yp5 )+(Yv1 +Yv2+Yv 3+Yv4+Yv 5) 400 400

JIS 5 longitudinal magnification of that mean

line of the that roughness curve, and (560) (560)

calculating the sum of the mean of the absolute values of Yp and that of Yv. Remarks: The designated values in the brackets do not apply unless

and wavy (~) symbols, were abolished.

N