| | | | | | | | | | | | | | | | | |
| | | |
| | | Abrasives' grit size. Abrasives' grit size is the size of the grain they contain. This influences a series of factors, among which: • the polishing of the workpieoe • tools cutting capability in the given unit of time | | |
| | | Gross machining Finishing Semiflnishmg 70-220 240-1000 (medium grit size) (fine) | | |
| | | 1200-... (superfira | | |
| | | |
| | | |
| | | N.B.: in glass processing the grit sizes normally range from 50 to 400 mesh for conventional abrasives and from 60 to 20 urn (micron) for | | |
| | | International standards set down how grit size: should be evaluated; Vincent normally uses FEPA's standards. FEPA sets down two grit sizes measurement | | |
| | | |
| | | |
| | | ui.ma,i.u.j,;« | | |
| | | |
| | | | | | | | | | | Denomination FEPA and ISO BIDS 46 | (ASTM11)IS0565 325/400 | Nominal mesh openings in urn ISO 565 45/38 | | | | 54 | 270/325 | 53/45 | | | | 64 | 230/270 | 63/53 | | | | 76 | 200/230 | 75/63 | | | | 91 | 170/200 | 90/75 | | | | 107 | 140/170 | 106/90 | | | | 126 | 120/140 | 125/106 | | | | 151 | 100/120 | 150/125 | | | | 181 | 80/100 | 180/150 | | | | 213 | 70/80 | 212/180 | | | | 251 | 60/70 | 250/180 | | | | 252 | 60/80 W | 250/212 | | | | 301 | 50/60 | 300/250 | | | | 302 | 50/70 Wl | 300/312 | | | | 356 | 45/50 | 355/300 | | | | 357 | 45/60 wl | 355/250 | | | | 358 | 45/70 Wl | 355/212 | | | | 426 | 40/45 | 425/355 | | | | 427 | 40/50 W | 425/300 | | | | 501 | 35/40 | 500/425 | | | | 502 | 35/45 Wl | 500/350 | | | | 601 | 30/35 | 600/500 | | | | 602 | 30/40 W | 600/425 | | | | 711 | 25/30 | 710/600 | | | | 712 | 25/35 Wi | 710/500 | | | | 851 | 20/25 | 850/710 | | | | 852 | 20/30 W | 850/600 | | | | | 18/20 | 1000/850 | | | | 1002 | 18/25 wi | 1000/710 | | | | 1181 | 16/18 | 1180/1000 | | | | 1182 | 16/20 | 1180/850 | | | | | | | | | | |
| | | • micron (urn) scale The mesh scale refers to the number of holes that can be counted along the side of a squared inch sieve; the bigger an abrasive grain is, the lower its mesh value (a 10 mesh grain is sieved through a squared inch sieve with 100 holes, a 30 mesh grain through a sieve with 900 holes, etc.). | | |
| | | |
| | | The micron scale measures grain dimensions in micron; the bigger the abrasive grain, the higher its value in micron. This scale is used to evaluate the rr grains of superabrasives. | | |
| | | |
| | | |
| | | | | | | | | | | | | | | | | |