Fit a chevron or cleated belt.

Shows the danger of using data that you haven't proved for yourself doesn't it

You can't believe everything you read, even if it is in a "standard". ■

There are possibly multiple solution with differing costs:

1. Please provide the belt width, idler angles, belt construction and concave radius

2. Please provide the size distribution and material shape characteristics

Rollback on material stream surface must be reduced. Once I see the configuration, I can model, in elementary construction one or more methods to control/reduce rollback to an acceptable level. ■

Problem is serious and also interesting.

Can you show the layout drawing? ■

More Information Required:

1. Product shape - brief description of shape if round or oblong, slabby, etc.

2. Conveyor profile from feed point to discharge - your description indicates the belt changes direction 7.5 m from feed. Does this include the skrt length? Does the dimension between skirt end and begining of vertical curve? What is skirt length and width?

3. Does the rock (Char) roll back at begining of vertical curve as well as distant end or only as belt rises to 22.3 degrees?

4. Is roll back only occur at the end of a feeding stream or when ore stream has load?

5. Does belt conform to trough shape or not? Describe details or show dwg.

6. What is belt cover thickness top and bottom and total thickness?

7. What is temperature range you operate at? ■

Also need bulk density. ■

Dont forget thevertical curve radius value, as previously requested, to check that belt curvature is not adding to material turbulence. ■

In this business the devil is in the detail.

No detail, then generalised help only.

It is a burden for the questioner to ask the right questions. ■

I'd still be thinking of changing to a chevron/cleated belt unless Mr Nordell can come up with a good alternative. ■

Initial comment upon visualizing your schematic:

Remove the shallow initial 12 degree slope and connect the two slopes (12 & 22 degrees) into the original single slope at your +/- 18 degree incline. You are loading at such a low belt speed, there will be less instability at 18 than at +22 degrees. There also seems to be a discontinuity (no vertical curve radius transition between slopes) at the intercept of the two slopes which will require an additional jerk response.

You could also benefit from an appropriate loading chute to enhance material stability. ■

Dear Mr. Kundu,

If the solution proposed by Nordell serve your purpose please do it. This is the simplest solution.

Otherwise, following methods can be adopted:

1.Use of Steep angle conveyor belts

2.Use of belts with moulded cleats

3.Use of tube/pipe conveyor belts

4.Adjust the present belt speed

5.Reduce the intermediate inclinations

6.Adjust the troughing angle wherever required

Combination of one or two above methods will give you desired result. I think problem can be resolved without much complication. Challenge, here is to solve it at an optimum cost.

If you require review in detail, you may contact me in the address mentioned below.

With regards,

cbray

Techgroup Solutions

62, Rajendranagar, Ground Floor,

Sakchi, Jamshedpur - 831001

Jharkhand, INDIA

Tel: 91 657 2228921

Mob: 91 9931114980 ■

Originally Posted by cbray

Otherwise, following methods can be adopted:

1.Use of Steep angle conveyor belts (sandwich belt elevator??)

3.Use of tube/pipe conveyor belts

cbray

Techgroup Solutions

I'm no belt expert, but might not these two options be a little expensive for this application?? ■

"Steep angle conveyor belt" - I wanted to mean pocket type with corrugated side walls (Flexwell/Metso make).

Option 1,2,3 all are costlier than conventional belts. ■

Originally Posted by cbray

"Steep angle conveyor belt" - I wanted to mean pocket type with corrugated side walls (Flexwell/Metso make).

Option 1,2,3 all are costlier than conventional belts.

Ah, I understand what you are talking about now. Sidewall belts are expensive and would require replacement of all the idler sets.

I'm back to chevron cleated belts which can replace the smooth belt with minimal modification combined with an increase in belt speed to reduce the belt loading so making the cleats more effective.

As I read the problem everything is in place, but the conveyor just isn't working properly so someone has some warranty charges to absorb in getting it to work. Or worst case they'll have to take out the conveyor and refund the money.■

Dear Mr. Kundu,

In my opinion taht the maximum slope for trough belt conveyor should not be more than 16 deg. for fines & that for lump is 12 deg. Beyond this you have problem of roll back of material. I think you misunderstood IS- 8730. Please read the IS very carefully before you implement.

A pipe conveyor can transport material at 25 deg. only. Not trough belt conveyor.

I think with out modifying the existing structure you can use rough top belt / cleated belt as suggested by Mr. Designer. This will reduce the problem. If possible also increase the belt speed that will also help in better way.

Regards.

A.Banerjee ■

Dear Mr. Kundu,

The bulk density of char would be 1.37 ton. cub. m if it is from cooler of DR Plant.

Regards.

A.Banerjee ■