First we should have more information.

1. - Is the load the same in both directions?

2. - Is the speed the same in both directions?

3. - Are there any inclines / declines in the system?

Problems you can encounter are:

a. - Belts are normally trained in one direction - when reversed you introduce a completely different set of loads on the idlers causing mistracking in the opposite direction. This can be corrected with special training idlers designed for reversing conveyors.

b. - Belt scrapers can be a problem when reversing belts.

c. - Backstops are not able to be used when reversing belts.

d. - Skirt boards can act as ploughs throwing material off the belt.

I am sure others will have more info to add to this but these are from my own experiences.

Regards,

Gary Blenkhorn ■

Dear Shri A K Bhatnagar,

Mr. Gary Blenkhorn has drawn your attention to very important issues concerning the reversible belt conveyors. This needs to be taken care of while deciding the technical features of the belt conveyors. In addition, please take special care for proper tolerances in fabrication and erection of the conveyor.

Regarding the type of drive and take-up, I would like to inform you as below :

1) For 300 m horizontal reversible conveyor, it is better to have drive unit at both the ends (one can also design such conveyor with drive unit at one end, but you will find the solution expensive).

2) The both end drives will result in less variation (change) in belt tension whether conveyor is running in one direction or the other direction.

3) You will observe that the belt tensions acting on most of the pulleys (which are on return run) are less. So economy in pulleys.

4) You can have a gravity take-up or winch take-up. The conveyor is to be designed accordingly.

It is probable that your conveyor may be a yard conveyor with stacker reclaimer machine (“reversible”) type. Many power stations in India have yard conveyors of 300 m to 600 m length, running in reversible direction, capacity range 500 mtph to 1200 mtph and at few places it is likely to be close to 2000 mtph. So, the issue is not uncommon and you can even see such installations.

Regards,

Ishwar G Mulani.

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

Email : parimul@pn2.vsnl.net.in

Tel.: 0091 (0)20 5882916 ■

Reversing belt conveyors do present unique problems as far as cleaning, sealing, and tracking.

1. Dual drives, one on each end allows for best tracking. Center drive location also works well.

2. Ensure belt is selected correctly, PIW, trough angle, bend radius, transition distance, temperature, chemical resistance and ratio of top cover to bottom cover thickness. If not done correctly at the start, long term problems will occur that will make the belt virtually impossible to track.

3. Martin Engineering supplies belt cleaners and reversing tracking devices that perform extremely well. For specific recommendations we would need specifics such as belt width, material conveyed, belt speed. ■

Originally Posted by I G Mulani

Dear Shri A K Bhatnagar,

Mr. Gary Blenkhorn has drawn your attention to very important issues concerning the reversible belt conveyors. This needs to be taken care of while deciding the technical features of the belt conveyors. In addition, please take special care for proper tolerances in fabrication and erection of the conveyor.

Regarding the type of drive and take-up, I would like to inform you as below :

1) For 300 m horizontal reversible conveyor, it is better to have drive unit at both the ends (one can also design such conveyor with drive unit at one end, but you will find the solution expensive).

2) The both end drives will result in less variation (change) in belt tension whether conveyor is running in one direction or the other direction.

3) You will observe that the belt tensions acting on most of the pulleys (which are on return run) are less. So economy in pulleys.

4) You can have a gravity take-up or winch take-up. The conveyor is to be designed accordingly.

It is probable that your conveyor may be a yard conveyor with stacker reclaimer machine (“reversible”) type. Many power stations in India have yard conveyors of 300 m to 600 m length, running in reversible direction, capacity range 500 mtph to 1200 mtph and at few places it is likely to be close to 2000 mtph. So, the issue is not uncommon and you can even see such installations.

Regards,

Ishwar G Mulani.

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

Email : parimul@pn2.vsnl.net.in

Tel.: 0091 (0)20 5882916

Dear Mr. Mulani,

would you please give us more information about reversible yard conveyor with stacker reclaimer machine.

Thanks a lot. ■