Have you done any real search yourself before bleating for information which you could find with a bit of a Google? You're posting on a website which has a bookshop, numerous technical articles & links to manufacturers' websites. Go back & start again.

"I want to learn" is one thing "carrying your books to school" is quite another.

Anyway:

The equipment to which you refer is largely proprietary & it is often wrongly assumed that certain manufacturers have developed secret formulae to rely on. This is very rarely the case & most such manufacturers are working in the dark with a flimsy success record. Every time I challenge manufacturers of more specialised equipment to justify their design with calculations I run into a wall of silence which crumbles with every subsequent interrogation. I have often had to develop my own calculation process to satisfy myself of the equipment integrity: which of course leaves the student knowing more than the master. Such is mineral process engineering science where a performance guarantee is unheard of. No doubt some excuses will follow.

Analyse the machine activity to determine the acting loads. This will also involve the worked material properties which is always the major stumbling block. Do not be perturbed, the properties can be found if you look hard enough. Do not trust a supplier who will not substantiate his claims with hardcopy. ■

You're quite right: you can't sell what you can't make & you can't make what you can't draw. (An old German philosophy that I learned in the 1970's)

Apron Feeders have been widely discussed in the forums.

Paddle Feeders are not so well discussed but there is only a sliding plane & a shearing plane to consider.

Wagon Tipplers are a compromise between neutral equilibrium & wagon geometry ie losses apart, the release mechanism & a proper counterweight connection should allow the load weight to displace the assembly almost automatically. Acceptable return motion is up to the counterweight linkage.

Ring Granulators, I haven't a clue.

Double Roll Crushers are explained in many mineral process textbooks; Wills - Mineral Process Technology is good place to start & has many references for further reading.

When you get stuck it is not unreasonable to simulate the conditions in an FEA situation which can be arranged to show the forces normal to the model surfaces. COSMOS Motion & ANSYS are my favourites for this kind of work. ■

Originally Posted by louispanjang

You're quite right: you can't sell what you can't make & you can't make what you can't draw. (An old German philosophy that I learned in the 1970's)

I must quote this to some salesmen I know.

They are quite happy to sell what hasn't been made or even drawn.

And they can get most stroppy when you try to point out the error of their ways. ■

Adnan,

Knowledge is one thing; wisdom is a combination of knowledge and experience. Lots of that available here.

Michael Reid. ■

For ring granulator crusher you can rely on the bond's third theory of comminution inorder to work out the power required.

However in this regard, I would like to raise a question to the experts. Recently I came across a term called blast factor. As per bonds equation W= Unit Power/TPH= 10 x WI x [{1/(PS x100)^0.5} - {1/(FS x 1000)^0.5].

Where WI= Work index= 435/ HGI ^0.91

FS= Feed size

PS= Product size.

However recently I saw a "blast factor" multiplied with the RHS of the above equation. Can anybody explain what this factor is? How do we select it? ■

Originally Posted by louispanjang

........it is often wrongly assumed that certain manufacturers have developed secret formulae to rely on. This is very rarely the case & most such manufacturers are working in the dark with a flimsy success record. ....... Such is mineral process engineering science where a performance guarantee is unheard of. ..This will also involve the worked material properties which is always the major stumbling block. ..... Do not trust a supplier who will not substantiate his claims with hardcopy.

Louis' earlier reply covered a lot of manufacturers' disregard and arrogance towards their customers. Bond Index stuff has been quite well documented over the years and with 'blast factor' I suspect that some manufacturer has coined the term to increase the size of his crusher. Rock that was around 200x 10⁶years ago doesn't become that much harder to break between the Bond equations and the present day. If such manufacturers wish to challenge the Bond theory they should come clean and develop further. ■