Factors to consider for selecting grinding steel ball
Views: 1886 Update Date:Jun 04 , 2018
With the help of grinding steel ball, the milling process is the most important operation in a mineral processing plant, its main objective being to break rocks to an adequate particle size. These grinding media are subjected to a strong erosion and electrochemical corrosion by the action of oxygen, mainly, whose wear forces to replace them periodically producing a consumption of more than 5 thousand tons of steel per year.
Mining plants that own smelters and use oxygen in their copper fusion operations extract this gas from the air by cryogenics, that is, they compress the air to the liquid state and later oxygen is obtained by controlled expansion of the liquid air, releasing practically everything nitrogen again in the air, except for some applications in the area of Moly flotation.
This grinding steel ball discovery, which is in full stage of patenting, entitled “Inhibition of corrosion of grinding media in wet milling of minerals by nitrogen action with duplex effect in the gas atmosphere and in the pulp of minerals”
The selection of grinding steel ball depends on several factors, some of which are interrelated:
Initial feed size
– Smaller grinding steel ball cannot disintegrate large particles.
Final particle size
– Smaller balls are more efficient when ultrafine particles are desired.
Hardness
– The higher the hardness of the grinding steel ball, the better the grinding efficiency and consequently, the balls will have less wear.
Specific gravity
– In general, high density balls give better results. The balls must be denser than the material to be ground. Also, high viscosity materials require balls of higher density to prevent their flotation.
pH
- Some strong acids or alkaline slurries can react with certain types of metal balls.
Discoloration
– Certain grinding steel ball develops a color and therefore is not suitable for the production of certain materials such as white coatings.
Costs
- Balls that can be 2 to 3 times more expensive can last considerably longer and therefore, are worth the additional cost in the long term.
Pollution
- The material that results from the wear of the balls affects the product and it may be necessary to remove it with a magnetic separator, chemically or through a sintering process.
