The Ball Tube Mill is basically horizontal cylindrical tube
rotating at low speed on its axis, whose length is slightly more
to its diameter. The inside of the Cylinder shell is fitted with
heavy cast liners and is filled with cast or forged balls for
grinding, to approximately 1/3 of the diameter. Advantages of
Ball tube mills include high availability, low maintenance,
constant capacity and fineness, hard and abrasive fuels ground
efficiently, large reserve capacity, increased fineness at low
loads ,fast response of over range ,low air to coal ratio,
ability to pulverise a wide range of coals, virtually unaffected
by foreign material flexibility of available capacity.
- Horizontal type slow speed in the range of 13-20 rpm.
- Pulverisation of coal by attrition and by impact of hard balls
- Speed reduction achieved by gear train consisting of reduction
gear box and large spur gear.
- Coal can be fed and removed from both sides of the mill.
- Half mill operation for partial loads allowed.
- Input coal size 25 mm white output is 70 to 90 microns
- Very high coal fineness achievable.
*At following parameters:
- Maximum ball charge
- HGI : 50
- Fineness : 70% through 200 mesh
- Total Moisture : 10%