YES,

Before the US Bureau of Mines(USBM) was disbanded, in mid 1990's, it funded a white paper (I believe it consists of 3 volumes - I have them somewhere in our archived documents) on the many forms of bulk transport by conveyor belt. Levitation was one method sponsored by USBM. A prototype was built and tested. It was heralded as a best method but never received commercial support from any venture capitalist.

Since then magnets have been improved and may yet have application advantages.

There are drawbacks and quirks, as I remember from reading the initial and follow-up info and testing. on mfg., engineering and operations.

Proper design, of conventional belt conveyors, can bring the horizontal rolling losses to less than f=.008 parts per ton of rolling stock. The number is pretty low and getting lower.

Lawrence Nordell

Conveyor Dynamics, Inc.

email: nordell@conveyor-dynamics.com

website: www.conveyor-dynamics.com ■

I have read your posting with great interest,

as a mechanic with 22 years in the mechanical maintenance field who worked on underground conveyors a lot, in my personal opinion the conveyors are a very poor type of haulage.

I realize fully that equipment costs are what drive any decision.

I in my opinion capsule pipelines are the way to go. The first costs are almost the same but and this is a big but- the cost per ton mile is much less.

The major differences are that the capsule pipeline can go for a hundred miles with blower booster stations along the pipe line that the capsule trains ride in with out transfer points and additional drives at each transfer point.

You can deliver as much ore as the pipeline timing and diameter will allow and add additional trains to deliver the ore, and it can put electricity back in to the system if synchronus motors are used.

Belt conveyor systems also allow for increased tonnage if the ore is finely crushed and or the belts are overloaded which puts additional strain on the driven and drive pulleys, pulley lagging,

pulley bearings, speed switch/speedswitch bearings, drive unit weldments etc., not to mention the cable on cable supported conveyors, hydraulic take up units and the conveyor belt it self, you have to always remeber that the drive unit is always pulling the belt weight as well all the time-it is a lot of wasted machinery power in this mechanics opinion. ■

We can cerainly make a case for any love of life. I do belts and you do pipes. I understand belts and I assume you understand pipes. However, I admit that I do not understand pipes as well as belts and would not argue the case. Each to their own and be willing to measure the true limits of man and machines with the best technologies of the free market.

LKN ■

Hi nordell, my problem with these systems is that they will be abused and used and abused. in my case they always overloaded the damn belts and we all suffered the consequences

-for instance one year they went cheap crazy and bought a 2 ply belt for 900 ton per hour 42 inch belt we went for several days with spills, and poor tracking of belts reduced production just to save a buck, it did not help matters that we did not put training idlers in the belt lines as a rule. Anyway the friction equation will always be there. lzaharis ■

Your concerns should be directed at the incompetents:

1. poor design criteria that addresses bad operating procedures

2. poor belt specifications

3. incompetent purchasing agent

4. bad operating procedures

LKN ■

Hi Mr. Nordell, I agree with you entirely, the problem is that the ones that make all the decisions run things from the top down and to this day 5 years after I was fired things are still the same

as long as they can mine rock salt cheaply and only have to pay the state of new york 25 cents a ton royalty it will not change

Besides that THEY ARE GOD!!!!!!!!!!!!!!!!!!!!!!

Sorry about the poor answer but that is what I had to put up with for 22 years-manure flows down hill :^) ■