Originally Posted by sganesh

Dear Experts,

Is there any relation between belt speed Vs Belt Width. For 650 mm belt width what could be the maximum speed ? Is 1.96 m/sec advisable for 650mm belt width conveyor?

I feel, if the belt speeds are less they would give better life. Request to post your opinions.

Regards,

It depends on a whole lot of things.

The higher the speed, the longer the loading skirts to make sure the material forms up on the belt.

The higher the speed the more you need to do at the discharge point to absorb the material speed as it comes off the belt.

The higher the speed, the greater the chance of dust problems.

The higher the speed, the greater the potential wear at the loading point.

The higher the speed, the larger the idler size to stay within rotational speed limits.

The higher the speed the longer the start up and run down times.

Large lump sizes do not like high speed as you do not want to be hurling -500 lump material at high speed off a belt.

The higher the speed, the lower the kg/m for a given throughput, so the lighter the load on the belt and the lighter the structure supporting the conveyor..

You have to look at space restrictions that might dictate the belt width and therefore speed.

But in all of this, you cannot give any single simple answer and it is not necessarily negative or positive. You have to look at the system and then decide on what the appropriate speed would be. ■

This one is one of the best answers i read on this forum. Thanks. ■

Originally Posted by sganesh

Dear Experts,

Is there any relation between belt speed Vs Belt Width. For 650 mm belt width what could be the maximum speed ? Is 1.96 m/sec advisable for 650mm belt width conveyor?

I feel, if the belt speeds are less they would give better life. Request to post your opinions.

Regards,

Belt life is better expressed in tonnes. On that basis it is only necessary to design the feedpoint correctly. "Only" is not so simple, as mentioned elsewhere . Belt length is not optional but it affects the life and so does the loading regime, which is highly optional. Climatic conditions can influence the belt life. Roughly speaking we try to balance the rubber cost against the target life so that the wear limit is reached just before the remaining rubber deteriorates under ozone and UV attack. ■

The width selection is driven by ore containment (lump size), terrain difficulties, belt strength, technical know-how and economics.

There are belts in operation, at about 700 mm, that run at close to 6 m/s. There is no restriction, other than the short and long term economics. NPV of operating costs vs. capital cost.

You might also ask, what are the limitations of stopping?

Narrow belts may have troughing issues if the belt strength is beyond troughability for the idler trough angle. There are too many attributes to name that govern the width selection in detail. Experience is the belt teacher. Look at KPC running at 8.5 m/s with a 1100 mm wide belt. Is this good or not? Can we run faster than 8.5 m/s with a narrower belt? It all depends on the design factors. In a one word answer, yes. So, the real question should be - what are the restrictions to running at 7, 8, 10 m/s? Is is belt width limiting, idler speed limiting, horizontal curve spillage, or many other factors that are in the domain of the designer and the technology format. ■

Other wear and width points:

Prior comments note life of belt. This is important with shorter belts < 1km. In longer belts > 5 km, the speed vs. life factor is less an issue. In most modern belt designs, the transfer chute sets the minimum life standard. Taking Palabora (South Africa) as a benchmark, the conveyor is 1.1 km long carrying 6500 t/h up a 16 degree incline, transporting up to 300 mm lump at +4 m/s. Bad chute = ~ 2 years of life, and good chute => 20 years of life, maybe as high as 30 years.

Palabora was 1800 mm wide, 18 x 9 mm covers, with a belt strength of ST-6600 N/mm. Belt would have troughing problems with a much narrower belt. The wide width was chosen to keep the strength rating within know belt design techniques in 1988.

Today, we see many belts approaching 8 m/s for many widths. High speed is not for everybody. Another criteria is maintainability. High speed means more maintenance and a higher level of technology for belt, idlers and chutes. ■

1.) Belt speed can be related to belt width in that what is fast for a 800mm belt does not seem at all fast for a 2000mm belt. Heaviness of the belting and components including larger diameter rolls do affect the acceptable speed but they are not the only factors. CEMA (Conveyor Equipment Manufacturer's Association) recognizes this relationship in their guidelines for belt speed according to belt width.

2.) Without knowing more about your system, a belt speed of 1.96 m/s seems very reasonable for your 650mm wide belt.

Joe Dos Santos ■

Originally Posted by sganesh

Dear Experts,

Is there any relation between belt speed Vs Belt Width. For 650 mm belt width what could be the maximum speed ? Is 1.96 m/sec advisable for 650mm belt width conveyor?

I feel, if the belt speeds are less they would give better life. Request to post your opinions.

Regards,

CEMA Std suggest in its 4-1 table a speed for a width and depending of the material coneyed.

You can choose a lower speed than the table 4-1 for a better belt life and achieving the required capacity ■