1. You have not given the capacity

2. 10:1 reduction ratio is probably too large for a single pass reduction for any efficient comminution machine that is sized near capacity, unless you can determine size distribution of product on each comminution method and payback summary of each.

3. Slow breakage minimizes undersized rock

4. You require 40-60mm but screen to 10mm?

A slow speed roll crusher with a recycle circuit of oversize commenserate with the breakage curve of your product might be a good start. Otherwise you pay for the oversized machine to stay within product tolerances

Need to know the breakage behavior and particle breakage size ratios for energy delivery meithor to make an intellegent selection.

All this depends on throughput, and value of undersized product, power, wear of liners, et al. ■

You are definitely in the market for a WR Stamler belt feeeder breaker, a Bradford Breaker and a Spokane crusher for your task.

The WR Stamler belt feeder is a world proven portable primary breaker crusher and the spokane impactor(which is also trailerable with a generator to power it if needed) is also world proven as is the pennsylvania crusher(www.penncrusher.com) Bradford Breaker, and all three of the above mentioned units are available world wide.

The bradford breaker has screens in the rotary drum which screen out the various sizes of ore needed along the length of the rotary drum breaker and the oversize can be easily recirculated and rebroken with no trouble at all.

contact www.joyminingmachinery.com

for the WR Stamler belt feeder breaker

spokane crusher for your secondary circuit- you will not have any problems getting the results you need.

www.penncrusher.com

Disclaimer:

I do not represent Joy mining machinery, pennsylvania crusher or Spokane industries. ■

We use Stamler feeder breakers at our salt mining operation as primary crushers with great success. As Larry has mentioned 10:1 is quite a high reduction ratio - Industry norm is more like a 6:1 ratio for best efficiency.

Although we tend to run more in the higher reduction ratio with approx 1800 mm (6')(sometimes larger) down to 200mm (8-10") it does have an impact on throughput as it slows down when the larger lumps are in the crusher hopper as it chews its way through the lump and holds back other product from getting through.

We then send the primary crushed through a roll crusher to give us a 50mm (2" minus) product to then be delivered to the mill for final product sizing.

Stamler also make roll crushers that would easily go inline to give you a secondary reduction for your target product.

http://www.joy.com/jmm/products/stamlersurface.html ■

we can provide solution to produce railway ballast material with ROM feed 500 mm and maximum - 65 mm to + 25 mm in a single stage.send your enquiry to marketing@puzzolana.com ■

Dear Shri Sandeep,

For the Indian granite stone, widely used practice is to have jaw crusher to reduce incoming stone size of (-)500 mm to (-)150 mm. The next stage crushing can be either by cone crusher or two roll crusher which can reduce these to (-)40 mm or its nearby range, plus as well as minus. The choice of cone crusher or two roll crusher depends upon capacity and the prices. One can have closed circuit crushing after second stage crushing, depending upon the utility of the output from these crushers. For example, if any over size even by limited margin is not acceptable and also if one doesn’t want to waste the said material, then there will be close circuit crushing.

Regards,

Ishwar G Mulani.

Author of Book : Engineering Science and Application Design for Belt Conveyors.

Author of Book : Belt Feeder Design and Hopper Bin Silo

Advisor / Consultant for Bulk Material Handling System & Issues.

Email : parimul@pn2.vsnl.net.in

Tel.: 0091 (0)20 25871916 ■

Dear Sandeep,

Generally, in Indian market basalt will be required for construction, where normally shape will be important. Roll crusher will generally give a flaky product [This will of course depend on nature of the stone]. But this is the machine will will give maximum % age of - 60+40. Other alternative is secondary Jaw crusher or cone crusher , depending on capacity required.

As suggested by Mr. Mulani, a close circuit is a must.

REgards

Ravindra Lele ■

Use a portable secondary like a Cedar Rapids Jaw/Roll combo. Feed with a primary of your choice (secondary has max feed size) and the feed goes across a screen deck. The top size goes to the jaw and bottom deck (mid size) goes to the rolls. Set screens, jaws and rolls to desired size, there is a formula for this. Finished product goes out the discharge belt where you can then screen out your products. ■