Contents
EVERY COMPONENT OF BALL MILL DETAILED & EXPLAINED
What is a End Discharge Mill (EDM)?
EDM =End Discharge Mill
Elements of Ball Mill – Overview
Mill Drive Concepts
Example Planetary Gear Drive
Planetary gear reducer concept MAAG
-Two gear stages with three planets
-All shafts with friction bearings
-Pinions, planets surface-hardened
-Annulus through-hardened
Gear Box Internals
Parallel shaft gear reducer (two way power branch)
– All gears surface-hardened and ground
-All shafts with roller bearings
-Key point:: Face load distribution of the LS-gear stage
Potential Technical Problems Drive
Girth gear drives – Fundamental Problems
1.Axial/radial runout
2.Alignment of the drive trains
3.Uneven power splitting
4.Centre distances variable
5.Face load distribution
6.Sealing of the girth gear
7.Girth gear is through hardened only, fatigue strength is limited
-Dynamic behaviour
-A lot of individual rotating masses risk of resonance vicinities
-Torsional/structural vibrations
-Pinion shaft bending vibrations
Gearboxes
Potential Damages Drives
Mill Bearing
Advantages slide shoe bearings:
- No size and capacity limitation of the mill
- Simple design of wear plates
- Far higher limit of gas temperature at mill inlet (e.g. for drying with heat generator)
Feed Arrangements for Ball Mills
Feed Arrangement (Example Step Feeder)
Elements of Ball Mill – Overview (Internals)
Overview Internal Elements
Liners for Coarse Grinding
Lifting Height Requirements (1st Chamber)
Classifying Liner for Fine Grinding (2nd Chamber)
Head Liners
Open Diaphragm (Drying Chamber Diaphragm)
Intermediate Diaphragm
Function of Intermediate Diaphragm
Intermediate diaphragm
Discharge diaphragm
Discharge Diaphragm
Material Quality and Application of Shell Liners
Life Time of Shell Liners
Grinding Media
Grinding in Ball Mill
Ball filling degree (f)
Steps of Grinding
Coarse Grinding: Parameters for Optimising
Grinding Media
Material Quality of Grinding Media
Specific Wear Rates of Grinding Media
Mill Efficiency
Lifting Liners Effects
Optimum Material Level 1st ChambeR
Optimum Material level 2nd chamber
Mill Ventilation
Cooling and Heating Possibilities
Fine Grinding and Mill Cooling
PROBLEM
Insufficient mill cooling lead to material agglomeration on balls and liners
The grinding is not any more done by balls against material but by material against material
SOLUTION
- Adapted mill cooling, playing with:
-Clinker temperature
-Mill ventilation
-Water injection
- Use of grinding aid (temporary solution because expensive)
Water Injection Systems
Please we are in need to catalouge for grate plate