Dear Mr.Bannerjee

Though sieve analysis is not given, still I feel with 25 degree inclination of the belt, of material having bulk density of 1.8t/m3, cleated belt is the best solution.

Regards

S.K.Bose ■

There are chevron belts available with ribs about 1" high, I think it is called "steepclimb". When used with troughed idlers they give pretty good capacity.

I used one years ago to take free flowing dried sand up about a 35 degree incline and it worked well except small round bits would work their way up to the surface and roll back to the bottom until buried under a burden where they couldn't get out before being discharged. ■

Mr. A. Banerjee

Your dilema is the best argument for sandwich belt high angle conveyors and their competitiveness when evaluated fairly.

By the nature of your approach to the problem whatever solution that you will choose will be at the limit, at the edge of failing. Too often the economic comparison of high angle conveying versus conventional conveying, in an elevating application, is based on a conventional conveyor that is on the edge of failure, say at 17 or 18 degrees. In a comparison of technically equal solutions (equal safety against roll back) the conventional conveyor would be at an incline angle of 12 degrees maximum. In such a case the economics will favor our sandwich belt high angle conveyor systems.

Joseph A. Dos Santos ■

What is the material? If it's wood chips, no problem @ a 35 degree incline. River sand, big problem.

Some of our patterns.

http://www.leggbelting.com/profiles.htm

Regards,

Ron Marler

www.leggbelting.com ■

Dear Shri A Banerjee,

The material name has been mentioned as DRI. Kindly mention the full name of material. In such steep inclined conveyor, the lump / grain size is also very important and also the shape of the grain. This means whether the grains are rounded and polished or they are odd shaped and would tend to interlock for achieving the conveying.

If your material happens to be average type with not very polished type of grains, possibly you will be able to convey at 25 degree, by use of herringbone type cleats on the belt. However, the experienced manufacturer of such belt will also be able to give you reliable information about the achievable inclination. Possibly you have to opt for comparatively slow speed conveyor and minimum turbulence during conveying i.e. somewhat less pitch of the idler compared to the usual practice, adequate tension and thereby sag value upto1%.

There are other types of steep belt conveyors also. This information you can get from various manufacturers.

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 25882916 ■