Crusher help

[jraef]

I do a lot of crusher controls (soft starters and drives) and one of my customers in another industry seems to think I am a crusher wizard. He is horribly mistaken. I can make them work, but have no idea as to deciding on the right one for the job. At least I hope I can point him in the right direction.

He is looking to reduce 200mm (8"-) down to 15mm (5/8"-) with one crusher, and at a rate of 90 tons/hour. His material is fairly hard, feldspar, and will be going into a secondary mill of some sort that will take the 15mm down to 1mm, so I don't see angularity as being an issue. I thought of a VSI, but can they take 8"-? Any other suggestions?

"Venditori de oleum-vipera non vigere excordis populi"

 

[CanuckMiner]

That's a 13:1 sizing ratio which seems high in my experience (limited to gyratory and jaw crushers, typically 5 or 6 to 1).

The following link mentions rotary or hammer mills as having higher ratios (40:1).

http://www.mcintoshengineering.com/...HRMH Rules of Thumb Edition 3 Web Version.pdf

Perhaps get in touch with Metso Minerals as they have rights to the Nordberg line of crushers.

http://www.metsominerals.com/

Cheers,
CanuckMiner

 

[rhodax]

I would agree with canuckminer: typical reduction ratio you can achieve with conventional crushers (gyratory and cone crushers) is 4 to 6. Check with crushers manufacturers suchs as Metso or Sandvik.
I would not recommend using hammer mills at all since feldspar is very abrasive and the hammers (wear parts) will not last. Operating costs will be an issue.
VSI could be an option but same problem about the wear , and feed size of 200mm is too large(contact Magotteaux to discuss the Magimpact with very special alloys for the wear parts).
In all cases, I believe you will need two stages of crushers