Dear Mr.Babak,

I understand the deviation you are referring is belt off-tacking.

There are 5 types of off-tracking. We may need more picture to understand your problem.

Please refer the table 14.1 in "Belt Conveyors for bulk materials " prepared by "Conveyors Equipment Manufacturer's Association (CEMA) ". Please refer.

It may be helpful for many problems you are facing in conveyors.

Regards, ■

Originally Posted by babak

HI dear friends

I want to know what are the reasons of belt deviation in general.

We have an inclined 24 inches belt conveyor that has always deviation.

thank you

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

Greetings and salutations Babak,

Please tell us what type of belt otherwise we are throwing darts at a dart board

in a blackened room with no windows while wearing blindfolds.

When you speak of belt deviation do you mean that the belt is not

tracking, meaning properly trained-when it is loaded or unloaded or both?

The easy one is-

If there is a significant build up of fines that will cause a side shift of the belt.

or the following;

1. The belt is stretched and needs a section removed.

(a) the belt is overloaded

(b) not enough tension on the belt when it is operating.

2. The belt wanders only in one spot during its movement; this entire portion of belt needs to be replaced.

3.The mechanical belt splice is failing and needs to be replaced

(a) the belt mechanical or vulcanized splices were never square to begin with when the belt was spliced.

4. there is a build of of fines affecting both the drive unit and tail pulley and it needs to be shoveled out.

5. If it is a cable supported or steel supported belt a belt stand may need to be realigned or one or more idlers are not the exact distance apart.

6. the belt stands must be the same distance apart also.

And saving the worst for last;

The drive unit and tail pulley were not properly surveyed and are not in alignment with each other.

lzaharis ■

Mr.Babak,

Let us walk along with the conveyor right from receiving chute.

1. Are you receiving the material at centre ?

2. How is the impact rollers ? Running free?

3. Is the tail pulley right angle to conveyor centre?

4. Are all carrying and return rollers are good? Running free?

5. Does the belt touch all the rollers?

6. Are the laggings of the pulleys, which are coming in contact with dirty side, not worn out ?

7. Is the conveyor adequately tensioned?

8. Are all pulleys and idler frames properly aligned with conveyor?

9. Is the conveyor joint good?

If you get any negative answer, correct it. Finally keep the belt track switches always in line.

Regards, ■

Like Izaharis says; we need a lot more information about the conveyor. Twenty four inches with an incline is a rather broad specification. ■

Dear Experts,

So far I have used ceramic lagging only for drive pulley to avoid slippage.

I am slightly nervous to use in other places. Because, if belt is offtrack because of what so ever reason, the ceramic lagging will not allow the belt to off track. This may affect the belt joints. Am I right in my thinking? Or I am unnecessarily worried?

Request your valuable opinions.

Thanks a Lot & Regards, ■

Spanesh,

Ceramic lagging does not have enough frictional resistance to harm the belt splice. In most cases, I believe, we would be looking at steel cord belt to necessitate ceramic lagging.

It will improve pulley lagging life. ■

Originally Posted by lzaharis

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

Greetings and salutations Babak,

Please tell us what type of belt otherwise we are throwing darts at a dart board

in a blackened room with no windows while wearing blindfolds.

When you speak of belt deviation do you mean that the belt is not

tracking, meaning properly trained-when it is loaded or unloaded or both?

The easy one is-

If there is a significant build up of fines that will cause a side shift of the belt.

or the following;

1. The belt is stretched and needs a section removed.

(a) the belt is overloaded

(b) not enough tension on the belt when it is operating.

2. The belt wanders only in one spot during its movement; this entire portion of belt needs to be replaced.

3.The mechanical belt splice is failing and needs to be replaced

(a) the belt mechanical or vulcanized splices were never square to begin with when the belt was spliced.

4. there is a build of of fines affecting both the drive unit and tail pulley and it needs to be shoveled out.

5. If it is a cable supported or steel supported belt a belt stand may need to be realigned or one or more idlers are not the exact distance apart.

6. the belt stands must be the same distance apart also.

And saving the worst for last;

The drive unit and tail pulley were not properly surveyed and are not in alignment with each other.

lzaharis

Dear Mr lzaharis

Sir

1) Why do we use stringer support at inclined portion for belt conveyor ?

rc ■

Originally Posted by guddu

1) Why do we use stringer support at inclined portion for belt conveyor ?

rc

Stringers locate the idler frames which in turn carry the rollers which provide support for the belt. With stringers the idler frames can be separated according to the requirement to limit sag. With too much sag there will be spillage and possible belt turnover. It's all a bit basic.

A stringer free system will be available soon: but it will not be dependant on the inclination or curvature of the belt conveyor. ■

Originally Posted by louispanjang

Stringers locate the idler frames which in turn carry the rollers which provide support for the belt. With stringers the idler frames can be separated according to the requirement to limit sag. With too much sag there will be spillage and possible belt turnover. It's all a bit basic.

A stringer free system will be available soon: but it will not be dependant on the inclination or curvature of the belt conveyor.

Dear sir

What is process to select belt width in belt conveyor?

For ex , i have to select the belt width for following

1) Material :- raw coal

2) Bulk density:-1.6t/m3

3) capacity:- 2000tph ■

Originally Posted by guddu

Dear sir

What is process to select belt width in belt conveyor?

For ex , i have to select the belt width for following

1) Material :- raw coal

2) Bulk density:-1.6t/m3

3) capacity:- 2000tph

What you need is to hire a consultant that understands how to design a conveyor for you. Give him the basics of what you want and go from there. You will be sorry if you try to do it yourself and it does not work. Very many factors involved in designing a system than simply knowing what belt width to carry a given flow requirement.

A good reference manual is "CEMA 6th eedition". All the formulas and methods are in there.

You are asking for free engineering services that is just not going to happen. The experience and knowledge comes with a price tag.

You keep jumping to into threads that have nothing to do with your questions. This makes it difficult for others to follow along in threads. Threads are to be kept on the original topic of discussion to make this board as best it can be.

Starting your own threads may be a wiser choice for you. And keep your questions in one threads instead of jumping all over the place. ■

Originally Posted by Gary Blenkhorn

......

You keep jumping to into threads that have nothing to do with your questions. This makes it difficult for others to follow along in threads. Threads are to be kept on the original topic of discussion to make this board as best it can be.

Starting your own threads may be a wiser choice for you. And keep your questions in one threads instead of jumping all over the place.

...And also make some attempts to compose realistic questions. ■