Originally Posted by Alireza

Dear Sirs

I wish you a happy new year.

I am involved in a design process of a long conveyor. Some questions occurred to me about the brake system. Does anyone has any experience in overland conveyor design?

First of all, what time I shall consider for braking at emergency stops? what is the design criterion or what guides line I can use for this purpose?

Secondly, For such conveyor the material and belt inertia will be significant. Is it possible for the belt to slide on the pulleys in case of wet condition? if it is possible, what can be done about that?

Another question is that of the head pulley stops (at fast brakes) is it possible that due the inertia, the take up pulley moves upward and release significant belt length which will cause creasing of the belt? a brake at tail pulley might help the carrying run, however, for the return run the problem still is present.

I also have another question which falls into another category. The conveyor has some horizontal curves. Is there any special recommendation about belt selection? Does anyone have experience in belt selection?

The conveyor specifications are as follows:

Design Capacity = 1000 tph

Conveyed material=Iron ore with D80=300mm

Bulk Density~2.2 t/m3

Horizontal Length=3500 m

Lift= -100 m

Horizontal Curve radius= 800 m

St-1000 Belt, Belt Width=1000 mm

Belt Velocity=2.1 m/s

If you need any other information, please let me know.

Thank you for your kind help,

Best wishes,

Alireza

Added by Moderator:

Brake for an overland conveyor

=================================================

Your question implies you do not understand conveyor design.

1. Do you wish a specialist to provide a design including all brake specifications and check other components to assure proper performance? You should seek a specialist with a proven record on such systems.

2. Do you wish free advice? ■

Originally Posted by Alireza

Dear Mr. Nordell

Thank you for your reply. You are kind of right. I maybe have a few experiences compared to you, but I am fairly familiar with the common methods. I am just trying to learn more.

Introducing a specialist will be helpful. However, I am looking for a guideline or a book or an article (not necessarily free!). Please note that my goal is to learn the brake design process. I have brought the parameters just to clarify my case.

As you can see I am looking for something between the two choices. After all, on some level, we all are here to learn something. aren't we?

Thank you.

Best wishes,

Alireza

==================================================================

Brakes can take many forms:

1. Electrical Force & Preset or Electronic Control - drive motor induced, electrical coil induced on brake pad, ...

2. Pneumatic Force & Preset, Fluidic, or Electronic Control

3. Hydraulic Force & Preset, Fluidic or Electronic Control

Spring Applied Force & Mechanical Release - all of the above

Mechanical Force as per above & Spring Release action and when it is the proper tool

Friction Pads vs. Non-Contact Retarder such as Voith Turbo Fluid Coupling, electro-magnetic, .....

Mechanics of heat build-up at pad surface, gasification of pad surface vs wear and force dynamics, pad physics, ......

Regulation can take many forms:

Regulation should be coupled to Belt Elasto-Transient "Dynamic Analysis" i.e. belt = rubber band with stress/shock/displacement wave propagation that must be solved together with Ideal Brake regulation for proper results and resulting force on terminal pulleys. Ideal Brake may be force or cost related. Ideal Brake may be location related according to available hardware, software, maintenance capabilities, safety margins to be applied to Fail-Safe methods, .....

Belt response in multiple degrees of freedom along its path (horizontal & vertical curves) including take-up system with or without regulation (gravity, fixed, controlled)

Coupling brake hardware and the response of valves, sensor components (tachometers, ....), hydraulics or pneumatics & piping, inertia in calipers and piping through valves, ......

Feedback loop regulation from electronic perspective, software sensitivity to loop timing, P&ID loop design, and hardware performance

-----------------------------------------------------------------------------------------------------------------------------------------------------------

I have named a few key design properties of common brake systems. The above is not exhaustive, but, an introduction to typical necessities.

Such a book does not exist, for these features, to my knowledge.

Good Luck In Building Your Technology ■

Originally Posted by Alireza

Dear Sirs

I wish you a happy new year.

I am involved in a design process of a long conveyor. Some questions occurred to me about the brake system. Does anyone has any experience in overland conveyor design?

First of all, what time I shall consider for braking at emergency stops? what is the design criterion or what guides line I can use for this purpose?

Secondly, For such conveyor the material and belt inertia will be significant. Is it possible for the belt to slide on the pulleys in case of wet condition? if it is possible, what can be done about that?

Another question is that of the head pulley stops (at fast brakes) is it possible that due the inertia, the take up pulley moves upward and release significant belt length which will cause creasing of the belt? a brake at tail pulley might help the carrying run, however, for the return run the problem still is present.

I also have another question which falls into another category. The conveyor has some horizontal curves. Is there any special recommendation about belt selection? Does anyone have experience in belt selection?

The conveyor specifications are as follows:

Design Capacity = 1000 tph

Conveyed material=Iron ore with D80=300mm

Bulk Density~2.2 t/m3

Horizontal Length=3500 m

Lift= -100 m

Horizontal Curve radius= 800 m

St-1000 Belt, Belt Width=1000 mm

Belt Velocity=2.1 m/s

If you need any other information, please let me know.

Thank you for your kind help,

Best wishes,

Alireza

Added by Moderator:

Brake for an overland conveyor

===============================================================================

Yes, Conveyor Dynamics, Inc. (CDI) have experience with belt selection/specifications using a special steel cord construction with horizontal radii = 400 m at a similar tonnage, with more lift. Smaller radii are possible.

Lump = 300 mm is extreme at P80 (D80?) or 20% above the 300 mm level. With such large lump, it may be difficult to contain with extreme banking angles called for in horizontal curves. Such condition also requires special knowledge of trough angle and banking angles in curves.

Again no books on the subject. We use ROCKY DEM granular dynamics to load the belt and then subject the belt to horizontal curve forces, slopes, side travel based on tension dynamics, using belt Finite Element Method (FEM) to arrive at a design travel, granular motion, and belt/idler stress limits. I do not know of any book that would cover such a complex analysis. It requires too many specialty tools. ■

Dear Mr.Alireza Jafari

Good day.

Hope you have solve your problem with this conveyor,if not so, then you can contact me by email and let us see how we can help you.

Basically,we have many similar project experience...

Tks!

Yuanjun Dai 15010211297@139.com

Originally Posted by Alireza

Dear Sirs

I wish you a happy new year.

I am involved in a design process of a long conveyor. Some questions occurred to me about the brake system. Does anyone has any experience in overland conveyor design?

First of all, what time I shall consider for braking at emergency stops? what is the design criterion or what guides line I can use for this purpose?

Secondly, For such conveyor the material and belt inertia will be significant. Is it possible for the belt to slide on the pulleys in case of wet condition? if it is possible, what can be done about that?

Another question is that of the head pulley stops (at fast brakes) is it possible that due the inertia, the take up pulley moves upward and release significant belt length which will cause creasing of the belt? a brake at tail pulley might help the carrying run, however, for the return run the problem still is present.

I also have another question which falls into another category. The conveyor has some horizontal curves. Is there any special recommendation about belt selection? Does anyone have experience in belt selection?

The conveyor specifications are as follows:

Design Capacity = 1000 tph

Conveyed material=Iron ore with D80=300mm

Bulk Density~2.2 t/m3

Horizontal Length=3500 m

Lift= -100 m

Horizontal Curve radius= 800 m

St-1000 Belt, Belt Width=1000 mm

Belt Velocity=2.1 m/s

If you need any other information, please let me know.

Thank you for your kind help,

Best wishes,

Alireza

Added by Moderator:

Brake for an overland conveyor

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