The important role of grinder mill on crushing ores
The crushing and grinding work of the ore is the preparation before screen.The prerequisite of mineral processing is to make a useful ores reached single separation.Due to the size of the useful ores existed by single is very small,sometimes it needs to grind the ores to reach 80% of powder's fineness less than 0.074mm,even smaller,it can make some useful ores reach single separation. While stone from the quarry is very large, such as, the maximum size of stone by open-pit mining can reach up to 1000mm,so it is necessary to crush the 1000mm large pieces of stone to into dozens of microns(1 micron = 1/1000 mm)size,it often go through several stages of grinding to finish.To crush,large-scale quarry often use the coarse,medium and fine,three crushing process(some also adopt 4 steps),to make the stone's size reduced to about 8-25 mm gradually,and then sent to grinder mill for grinding, until the useful ores can achieve single separation.Commonly,the using machinery is:Jaw crusher,Impact crusher,VSI crusher(Sand making machine),Cone crusher.
The grinding process is usually one or two steps,related the specific quarry,the scale of the quarry,the specifications of the using crushing and grinding equipments,the requires of the productions' fineness and others.The main equipments:The coarse crusher(the fine crusher or sand making machine),Raymond mill(High Pressure Suspension Grinding Mill),High pressure micronizer,to reach powders.
The index of crushing and grinding segments divided:
The type:
|
Name
|
Feeding size(mm)
|
Fineness(mm)
|
|
Coarse crushing
|
1500—500
|
400—125
|
|
Medium crushing
|
400—125
|
100—25
|
|
Fine crushing
|
100—25
|
25—5
|
|
Coarse grinding
|
25—5
|
1—0.3
|
|
Fine grinding
|
1—0.3
|
0.1—0.074
|
