I have worked in the Simla area near Ambuja and more recently with Lafarge. Your specifications reflect one route for Lafarge.

Is this a separate installation to these?

There are significant terrain difficulties that need to be addressed before a reasonable answer can be offered. In addition, you need to know more about the stickiness or surface moisture of the ore.

In principle, there are a number of options to allow either conventional, pipe, and other methods. Civil and Sturctural options to lessen civil work make up alternatives or options to transport 1800 t/h.

Some of the terrain I have recently studied includes terrain gradients of up to 30 degrees and almost 900m declines. These difficulties can be designed for with modern technology.

There are many conveyors that have gradients greater than 20 degrees. Going downhill is more difficult due to destablizing the rock. ■

Often the cost of the installation is greater then that of the chosen equipment. Such is the case when angle limitations require much excavation and elevated structure along a rugged terrain. The DSI sandwich belt systems overcome the angle problem and allow for a simple economical stringer structure that can closely closely follow the terrain. It was this advantage that made a Dos Santos Sandwich Belt system the most economical solution at an installation that elevated refuse rock 175 meters along 454 meters of length at a Virginia USA Mountain side. The profile is very irregular, conforming closely to the original topography, require minimal slope disturbance and minimal steel structure.

Additonally there is a synergy of similar belt wdth requirments at DSI sandwich belts and at pipe conveyors. This means that converting the pipe belt into a DSI sandwich belt, locally along the high angle slope, does not penalize the overall installation.

Joe Dos Santos ■

Are you saying that a pipe belt can be "opened up" at intervals along it's length and have a cover belt provided to form a sandwich belt conveyor, then "closed up" back into a pipe conveyor?

A novel arrangement. Are there such installations currently running? ■

Mr. Designer,

Yes, that is what I am saying. Furthermore, I would propose to drive the top belt as a booster (though the benefits go beyond drive boosting) unless it becomes logistically very difficult.

There are no such installations and we have only had a single opportunity to propose this. It may be that the pipe belt people erroneously view sandwich belt systems as competition rather than as a compliment and potential partner.

Joe Dos Santos ■

I like novel things, but sometimes it's difficult to try them out. Customers can be so conservative in their thinking :-(

Lets hope we get a response from one of those experienced with pipe conveyors! ■

Fairport Engineering Ltd could be of assistance to you in solving your conveying problem. We would refer you to our web site www.fairport.co.uk and if it is of interest we would ask you to make contact. ■