Dear J-S Ratelle,

Would you supply more information.

What type of material are you loading into the trucks (bulk solids such as stone, coal, etc.; boxed goods, finished product such as rebar, beams, etc.)?

As it appears that you wish to side load the trucks, what is conveyor movement do you need - or can you keep a stationary conveyor and move the truck?

Do you need a system that will load just one truck, or do you require something that will handle multiple trucks? If the latter, what is the total distance required?

Finally, what elevations are required? Is the load to be done with a level conveyor, an incline conveyor, or a decline conveyor?

There are a number of options available to you, depending on your needs.

Regards, ■

Dear Mr. Ratelle,

You have a number of options for single truck loading, some are listed below.

[1] Put the laoding conveyor on a rail system. The problem with this is that you have to contend with a changing conveyor load point or make the conveyor extendable and retractable.

[2] Make your conveyor an overhead tripper sytem. The main problems with this include clearance requirements for the trucks and additional dust generation because of the added drop.

[3] Use an elevated conveyor that feeds a pivoting chute. The main problems with this is the chute length required and those problems associated with the triipper possibility.

[4] Use a CAP system (CoAxial Pipe conveyor). This system appears to be an elegant solution to both dust control and discharge flexibility. The main problem with it is that it is a relatively new product and does not, therefore, have a history of successes or failures. I first learned of it at www.mining-services.com and you can obtain information at www.bosmin.com.

[5] Use wheeled portable truck loading conveyors such as those offered by a number of manufacturers (both troughed belt systems and corrugated sidewall systems). The main problems associated with these are the moveable conveyor load points, dust generation, and the spillage.

Obviously, there are other solutions, but this should get you started. Of the five possibilities listed above, I tend to favour the CAP or tripper approaches.

Regards, ■

Hello J-S.Ratelle,

You already have a good response from the readers with many useful suggestions and probable solutions.

It has been mentioned by you that the conveyor is required to load bulk material into open as well as closed trucks. The closed trucks immediately puts the restrictions on possible solutions.

1) If it is a closed truck, then mostly it will have fully open-able rear side. The other sides will not be usable for assess of equipment into the truck.

2) If the conveyor has to enter into the truck from rear side, it cannot have any support from the truck, and it may require telescopic arrangement for the conveyor discharge point to enter into the truck, and retract backwards as the filling progresses.

3) The speed of retraction and actual material on conveyor will be have automatic correlation, so that you get balanced loading along full length of truck.

For more specific suggestions from the readers, I suggest you to mention the truck body dimensions i.e. length width and height of enclosed space where the material is to be placed. Also, the load carrying capacity of the truck. Although you have mentioned 40 trucks in a day, which is not very specific, please specify the number of trucks to be loaded in one hour. How about the loss of time during changing of truck from empty to loaded etc.

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 25882916 ■

Dear Mr. J-S.Ratelle,

Referring to the additional information about the truck, the truck body dimensions such as length width and height mentioned by you, now makes the thing clearer. However, there is still some ambiguity. Please clarify whether you have feed-openings in the roof of truck. If so, you intend to load the closed truck through such openings in the roof. Now, what is the spacing / pitch of such openings in the roof? Please note that when conveyor discharge is shifted from one opening to another opening, there should be no discharge from the conveyor otherwise the material will spill over the roof when the conveyor discharge end is travelling from one opening to another opening.

The truck and the system picture shown by you does not have adequate clarity. Please see if you can attach a clearer picture of the arrangement.

Regarding travel of shuttle conveyor, primarily it can be by travel drive mounted on wheel shaft. The travel drive will have the brake such that when the motor is not operating brake will apply automatically and keep it stationary.

Other option to avoid this situation is to have something like plough discharge at the spacing of opening in the roof of truck. The material will get discharged at various ploughs simultaneously or one by one, which will flow into truck through the openings in the roof. This system will not need travelling shuttle conveyor, but it will have a stationary conveyor. Also, the chute from discharge plough should have swinging limited provision so that if the truck is marginally away from desired position, the chutes can be brought directly over the opening in the truck roof.

The specific solution depends upon exact data and requirements.

I trust the above information and suggested probable solutions may be of interest.

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 25882916. ■

Dear Mr. J-S.Ratelle,

Based on the sketch you supplied, the use of either a stationary conveyor with diverter plows (as suggested by Mr. Mulani) or a telescoping conveyor with discharge point proximity switches (or other I/O devices) would be appropriate.

Is this still in the conception stage, or are we talking about a problem resolution situation?

Regards, ■

Thank you for the pdf file drawing set. It appears that this is a proposal to have one existing delivery conveyor (345-BEC-450) to feed two truck-loading systems. Apparently, shuttle conveyor 345-BEC-460 currently is used for loading closed (tanker) trailers on scale 345-TRS-466, using extendable drop chute 345-LSP-464. Also, it appears that you want the delivery conveyor to also feed an unnamed conveyor for loading open trailers on scale 345-TRS-744, using a new extendable drop chute.

To do this, you need some means to feed both truck loading conveyors. This can be done by turning the delivery conveyor into a tripper system; by making the delivery conveyor a two-position extendable conveyor; by using diverter plows on the delivery conveyor; or by installing a separate delivery conveyor to feed the open trailer load station.

As far as the new shuttle conveyor is concerned, you can copy the existing system used for the tanker trailers or install a tripper conveyor to load the truck evenly without moving the truck.

I presume that the silos shown on the drawing (345-SIL-055 and future 345-SIL-065) do not have a bearing on your truck loading process.

It also appears that this is a project requiring some engineering design work and that you are with a company making a proposal. It is outside of the scope of this forum to provide detailed engineering services. If you wish to have another engineering company provide alternatives, you should contract for the work. Any recommendations that you receive using this, or other, forum will only have directional value ? detailed recommendations have a price.

Regards, ■

Ratelle,

Even so I agree with ADM on the issues of consulting, I believe that we are turning a small design problem into a complex machine.

If the load point is to remain stationary and the drop shroud move along to fill the truck, I don't see any difficulties in moving the conveyor on a rail arrangement. Today automation is not so expensive or difficult to implement.

All details for dust containment, reliability and cleaneness are just details and need to be included in the design stages of the project.

I think that your inquire tries to capture all those details and in my opinion, it is ok for you to ask. Maibe one day you can help me. However you need to be specific on what you want to know.

Regards,

Antonio Reis

Vitrom Mfg Consultants

Your Process and Manufacturing Solutions

Phone: 209.834.1900

Fax: 209.834.1039

www.vitrom.com ■

OK...I got have my 2 bobs worth as we have a good shuttle conveyor - if that is what U want.

Shuttle to run on steel rails with steel wheels...fit rail cleaners to keep on level

Drive to be a chain - chain is stationery with a spring tensioner at one end...chain to lay on the ground - on centreline of shuttle.

Drive to be mounted on shuttle - best at rear end - need 2 bend sprockets to bring the chain up to the driver sprocket.

Fit brake, VFD and other goodies to control the motion/postion.

For feed - have a sliding feed skirt design with stationery dust collection for the feed.

For the discharge - have a shuttle mounted dust collector to service the spout.

Spout to be telescopic with close off sealing cone and vibrator for cleaning plus level detection.

U will have an opening in the floor and U need to think of safety / fall hazards for personnel.

Easy Campese

Have a good day

Thanks

James Morrish ■

I have to admit that I was thinking much less complexity.

With the cost of the system you just described, I would prefer moving the truck.

The weight of the truck can be monitored with individual loadcells under the tires and you have a very simple symple system to design and build.

Good luck and let me know if you need further assistance.

Antonio Reis ■