| Beginners Guide |
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Information Sources:
Van Reenen & Nichols
Poly Hi Solidur
Multotec
Why Line ?
Chutes, silos, bins and hoppers are lined for two main reasons:
1. To protect the chute plates from excessive wear.
2. To improve the flow of material across the chute plates.
1. Protecting chute plates from Wear
The three main types of abrasive wear which occur
in mining and earth moving may be classified as follows:
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SCRATCHING
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GOUGING
Large particles move about over a steel surface under high pressure combined with hard impacts. |
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GRINDING
Small Particles are pressed between two steel surfaces. |
Mineral Hardness
When the average hardness of the materials is lower than that of the wear plate, the plate is exposed to only moderate wear.
However, when the hardness of the material is higher than that of the
wear plate, a wearing-down process begins. The harder the minerals the more rapid the wear and, generally,
the harder the wear plate the greater the wear resistance.
Hardness of some minerals in Vickers (HV)
Calcite 140 HV
Flourite 190 HV
Apatite 540 HV
Felspar 600 - 750 HV
Flint 950 HV
Quartzite 900 - 1 280 HV
In comparison, ROG LAST AH360
has a hardness at 360 - 390 Brinell (equivalent 380 - 400 HV).
Other factors affecting wear resistance
Other factors which affect
wear resistance of materials are:
1. Corrosion
2. Impact Angle
3. Velocity of Minerals
4. Lubrication
5. Particle Size
6. Particle Shape
7. Temperature
By lining the chute plates with impact and wear resistant liners, many of these wear problems can be overcome.
2. Improving the flow of material across the chute plates.
Very often plant managers and system designers are faced with the problem of bunkers, bins, silos and chutes continually hanging up.
These flow obstructions are caused by rat-holing, bridging or build-up of material on bin sides.
Many man hours are lost trying to clear these obstructions and bottlenecks.
By lining the chute plates with low friction liners, many of these problems can be overcome.
