Diamond abrasives
Selection of abrasive material
Abrasive material is decided by material of workpiece and bond type.
Abrasive material type and applications
table 1
Series |
Code |
Range of granularity degree |
Applying fields |
|
Synthetic diamond Cubic Boron Nitride |
RVD |
60/80-270/400 |
Be used to make grinding tools in resinoid/ceramic binder or for grinding etc.Good effect for grinding machine of cemented carbide. glass. magnetism material. |
MBD |
60/80-270/400 |
Be used to make grinding tools in metallic binder,plating products,drilling tools or for grinding ete.Suitabie for rough grinding or semi-finish grinding ef cemented carbide.glass.magnetism materials. |
|
MP-SD |
W0/0.5-W36/54 |
Mostly used for finish grinding or polishing of hard brittle and nonmetallic materials. |
|
|
Cubic Boron Nitride |
CBN I |
20/30-270/400 |
Be used to make grinding tools in resinoid binder,Suitable for grinding of mould steel. |
CBN II |
20/30-270/400 |
Be used to make grinding tools in metallic binder.Suitable for grinding of mould steel. |
|
MP-CBN |
W0/0.5-W36/54 |
Suitable for grinding or polishing of hard materials. |
Selection of grit
Roughness of work piece,grinding efficiency and abrasive material loss are all related with grit,which should be decided by the most important factor.Coarse grit will be chosen when roughness stand could be meet to improve grinding efficiency and avoid much abrasive material loss.
Grit number and grit size as table 2.
The relationship between grit number,roughness request of work piece and grinding procedure as table 3.
table 2
Grit |
Micro-powder |
||||
Grit number |
Dimension |
Grit number |
Dimension |
Granularity |
Dimension |
35 |
500-400 |
120 |
125~100 |
W40 |
40-28 |
45 |
400~315 |
150 |
100-80 |
W28 |
28-20 |
60 |
315~250 |
180 |
80-63 |
W20 |
20-14 |
70 |
250~200 |
240 |
63~50 |
W14 |
14-10 |
80 |
200~160 |
280 |
50~40 |
W10 |
10~7 |
100 |
160~125 |
320 |
40-28 |
W7 |
7~5 |
table 3
Granularity |
Roughness requirement of work piece |
Grinding procedure |
|
B |
M |
||
60/70-100/120 |
1.0-0.4 |
Rough |
|
100/120-140/170 |
0.4-0.2 |
0.8-0.2 |
Semi-finishing |
140/170-230/270 |
0.2-0.1 |
0.4~0.2 |
Finishing |
270/325-W20 |
0.1-0.05 |
— |
Finishing |
W14-W5 |
0.05-0.025 |
— |
Super grinding |
W5-W1 |
0.025~0.012 |
— |
Super grinding |
Selection of bond
Resin bond: high grinding efficiency,good self-dressing ability,and not easy to block,easy to be dressed,but not suitable for load-bearing grinding in case of fast abrasive material loss.it is mainly used for rough grinding,semi-finishing,finishing,edge grinding,polishing of cemented carbide,glass,ceramics,mould steel,etc.
Metal bond: suitable for load-bearing grinding with high compressive strength,good wear-resistance,long service life.it is mainly used for cutting,rough grinding,semi-finishing,and profiling grinding of stone,gem,ceramics,optical glass and fireproofing material,and rough grinding of cemented carbide inserts and electrolytic grinding.
Selection of concentration
Concentration means abrasive material content in the abrasive layer,which is mainly related with bond type and applications,usually as below:
①50%-75% is usually applied in resin bond wheels.
②100%-150% is usually applied in metal bond wheels.
③Higher concentration should be chosen for wider surface grinding,groove grinding and profiling grinding.
④High concentration for rough grinding,medium concentration for semi-finishing,lower concentration for finishing.
The relationship between diamond concentration and content
Concentration |
Code |
Content |
|
|
Diamond volume in the diamond floor |
Carat/cm |
||
25% |
25 |
6.25 |
1.1 |
50% |
50 |
12.5 |
2.2 |
75% |
75 |
18.75 |
3.3 |
100% |
100 |
25 |
4.4 |
150% |
150 |
37.5 |
6.6 |
Diamond:3.52g/cm³
Tips to improve grinding efficiency :
Selection of coolant
Kerosene、emulsion、water、transformer oil can be used for coolant proceeding grinding.
Attention:alkalescent coolant is not suitable for grinding-wheels in resinoid binder.
Coolant flux:3-8(l/min) is in commonly.
Selection of speed of grinding-wheel
Vc Selection of speed of wheels | ||
Bond |
Cool way |
Va(m/'s) |
M |
Dry |
12-18 |
Wet |
15-22 |
|
Vc Selection of speed of wheels | ||
Bond |
Cool way |
Va(m/s) |
B |
Dry |
15-20 |
Wet |
18-25 |
|
Selection of grinding allowance
Grinding procedure |
Plain grinding |
Cylindrical grinding machine |
Internal grinding machine |
Edge grinding |
ap(mm) |
0.005-0.03 |
0.002-0.02 |
0.002-0.01 |
0.01-0.03 |
To improve grinding efficiency. aluminum oxides wheels or silicon carbide wheels must be used to dress the surface of diamond and CBN grinding wheels,in order to make diamond and CBN abrasive material exposed from bond.
Diamond abrasives |
Dressing wheels |
||||
Bond |
Grit |
Grit |
Abrasive |
Hardness |
Bond |
material | |||||
M |
60-180 |
60-46 |
TL |
ZR2-Z1 |
A |
240 |
60 |
TL |
ZR1-ZR2 |
A |
|
B |
80-180 |
60 |
TL |
ZR1-ZR2 |
A |
240 |
80 |
TL |
R3-ZR2 |
A |
|
Overview of sketch and type code
OEM is more than welcome as customized drawing.
