18. Reference Information
No.99MBB122A
18-35
18.5.27 Rpk (JIS2001, ISO1997, VDA, Free): Initial abrasion height (peak height)
From the lines that are obtained by selecting 2 points (point A and point B) on the BAC
(material-ratio profile) that differ in mr value by 40%, obtain the line with the smallest
inclination. Set point C and point D to be the points where the obtained line intersects the
lines at mr = 0 and mr = 100. Set point H to the point on the BAC with the same slice level
as point C, and then set point I to the point were the BAC profile and the slice level at mr =
0 intersect. Next, set point J along mr = 0, so that the area enclosed by line segment CH,
line segment CI, and curve HI and the area of triangle CHJ are the same. Rpk is the
distance between point C and point J. (Initial abrasion height)
Rpk
D
G
H
C
A
B
E
A2
A1
Rk
Rvk
Mr1 Mr2
40%
J
F
Rpk
I
Rvk
mr[c] (%)