Grade of ceramic balls GB308-2002 ISO3290-1998 (E) Standard

 

Grade	Allowable Ball Diameter Variation (Vdws, um)	Allowable Deviation From Spherical Form (um)	Surface Roughness (Ra, um)
3	0.08	0.08	0.010
5	0.13	0.13	0.014
10	0.25	0.25	0.020
16	0.40	0.40	0.025
20	0.50	0.50	0.032
24	0.60	0.60	0.040
28	0.70	0.70	0.050
40	1.00	1.00	0.060
60	1.50	1.50	0.080

 

Grade	Lot Diameter Variation (Vdwl, um)	Gauge Interval (um)	Preferred Gauge (um)	Subgauge Interval (um)	Subgauge (um)
3	0.13	0.5	-5,......,-0.5,0,+0.5,......+5	0.1	-0.2,-0.1,0,+0.1,+0.2
5	0.25	1	-5,......-1,0,+1,......,+5	0.2	-0.4,-0.2,0,+0.2,+0.4
10	0.50	1	-9,......,-1,0,+1,......,+9	0.2	-0.4,-0.2,0,+0.2,+0.4
16	0.80	2	-10,......,-2,0,+2,......+10	0.4	-0.8,-0.4,0,+0.4,+0.8
20	1.0	2	-10,......,-2,0,+2,......+10	0.4	-0.8,-0.4,0,+0.4,+0.8
24	1.2	2	-12,......,-2,0,+2,......+12	0.4	-0.8,-0.4,0,+0.4,+0.8
28	1.4	2	-12,......,-2,0,+2,......+12	0.4	-0.8,-0.4,0,+0.4,+0.8
40	2.0	4	-16,......,-4,0,+4,......+16	0.8	-1.6,-0.8,0,+0.8,+1.6
60	3.0	6	-20,......,-5,0,+5,......+20	1	-2,-1,0,+1,+2