2、 Selection of Granule-Degree:
Coarse granule of abrasive materials bring better efficiency, while the surface of workpiece will be
rough.
In the condition of satisfy the coarseness of surface, it is better to choose coarse Grit-size.
It is better for Resinoid binder grinding tools to choose 70/80(80#)and following RVD(JR1) Diamond.
It is better for Metalic (bronze) binder grinding tools to choose MBD(JR2) Diamond.
Granularity number & Basal granule size of Synthetic Diamond or CBN will be seen in the former
sheet(Page.2).
CBN tools process ordinary steels, carbon steel and varieties of alloyed steel precede Diamond.
The relationship between Diamond granularity and process coarse granularity
Granularity number |
Reachable surface coarseness |
Original criterion of Industry Department |
Criterion of P.R.C. |
Resin Binder |
Metal Binder |
80#~100# |
70/80~100/120 |
—— |
△6~△8 |
100#~150# |
100/120~140/170 |
△8~△9 |
△7~△9 |
180#~240# |
140/170~230/270 |
△9~△10 |
△8~△9 |
280#~W20 |
230/270~12-22 |
△10~△11 |
—— |
W14~W5 |
8-12~4-8 |
△11~△12 |
—— |
W5~W0.5 |
4-8~0-0.5 |
—— |
—— |
The relationship between grinding procedure and granularity
Grinding Procedure |
Granularity selected |
Original criterion of Industry Department |
Criterion of P.R.C. |
Coarseness |
80#~120# |
70/80~120/140 |
Coarseness&Precision |
120#~180# |
120/140~200/230 |
Precision |
180#~W40 |
200/230~36-54 |
Grinding&Polishing |
W40~W1 |
36-54~0.5-1 |
|