Most refractory raw materials are supplied crushed or milled.

Crushers;

Jaw crushers are the commonest primary crushers. Cone crushers are also used as primary crushers. Roll crushers are used for finer crushing.  In a typical crushing plant you have a crusher and then a set of screens separating the different sizes and the oversize will be recirculated back to the crusher or to another comminution machine.  Refractory minerals are commonly supplied in 5 to 10mm, 3 to 5mm, 1 to 3 mm, 0 to 1mm, ball mill fines, dust extractor fines, minus 100#, minus 200# and minus 325mesh. Often confusion arises between 3 to 5mm and 325mesh.

100# = 150micron

200# = 75 micron 

325mesh = 45 micron

Comminution requires a lot of energy.  Imagine a cube of rock 100mm x 100mm x 100mm. Think how hard you need to hit it to split into 2 halves. 3 hits will split it into 8 pieces of 50mm x 50mm x 50mm.  150 such blows will split it into 1mm cubes. 4500 such blows will split it into 0,1mm cubes.  135000 blows will split it into 10 micron particles.  4 000 000 blows will yield 1 micron particles and 121 000 000 blows will split it into 0,1 micron particles.

Assuming you have already realised the value of ultrafine particles, you now appreciate the cost of manufacturing them. 

After crushing comes Milling.  Most milling is done in ball Mills. These are rotating drums with a charge of round alumina balls in them.  The balls sometimes have a range of sizes.  Big ball mills may take 30 tons.  Small laboratory mills may take 5kg and smaller Rosetti mills or swing mills take in the order of 100 grams.

Have you ever been inside the G&W Base Mineral resources plant?

They make use of ball mills – I’m sure because what I saw at HBM Engineering was either part of the mill drive or the discharge diaphragm

It was not the inner shell lining.

It is the constant rotation of the drive inside a stationary unit that wears the plate lining down not the material inside the mill chamber.

That is the part that I would like to have coated in an epoxy coating.

Do you have a datasheet or composition of the material you made up – the material that George from Technoresin tested/cut for you?