I've often wondered about that myself. It's not something I've ever use in 30 years of designing chain feeders/conveyors ■

Filling factor we have used while calculating the capacity of buckets of a bucket wheel reclaimer. I do not know about the filling factor of chain feeder. But can you write clearly what factor you want to calculate.

Regards.

A.Banerjee ■

Designer,

How would you then calculate the capacity of a chain conveyor (en-masse) with a flight height of 50 mm, width = 390 mm, speed = 0.05 m/s conveying fly ash at 700 kg/m^3. Buhler reckons that the material depth will be 185 mm, which I question.

Regards

Henk Fourie

FourieJH@eskom.co.za ■

Well it all depends....

What is the volumetric capacity that is being conveyed? Sizing of chain conveyors depends on the required volumetric capacity.

What is the operating principle of Buhler's chain conveyor? Is it drag scraper or en-masse?

How long has this Buhler company been supplying chain conveyors, 1 month or 50+ years? If it's one month maybe you should worry. If it's 50+ years maybe they know what they are talking about.

I see you're at Eskom. Aren't there a whole bundle of chain conveyors on fly ash at Lethabo and Matimba power stations ? Why not pay them a visit.

EDIT

These guys are in your neck of the woods...

http://www.batemanengineering.com/BE...sElevators.htm ■

The capacity of the conveyor can be easily calculated by factoring the area by the speed and density.

Rather elementary. Power got overlooked in the process. If the thread starter is trying to determine the shiftable bed depth then he must calculate the internal friction forces and balance them against the sum of the sidewall friction, apron friction and flight friction on the apron. We used to do it all the time in the good old days to determine the Power.

I agree with Henk that height=1/2 width is far too little and it suggests that moving bed bunkers won't work very well. But they do work very well and so although Buler have been around for eons; for once they are in question. As for filling factor??? ■

En-masse chain conveyors where a skeleton chain conveys material many times the depth of the flights without significant speed difference between the chain and material (hence en-masse) has been known since the early 1920's. Frequently referred to as REDLER conveyors, named after their originator Arnold Redler (search for patents under his name and that of the company he founded Redler Conveyors Ltd). Buhler had a licence from the 1930's. I believe "REDLER" is still a registered trade mark around the world.

There is little exact design information freely available, most real knowledge being held as commercially confidential by those companies who make them (or rather make them properly).

Generally speaking the load depth tends to be limited to the load width, but it's all dependant on the characteristics of the bulk material being conveyed. As with most materials handling equipment failure to understand the material being handled will end in failure.

The data provided by Henk is fine for an en-masse conveyor assuming the flights are correctly spaced. But as no capacity was stated we're a bit in the dark. And as I stated before, Eskom have loads of en-masse conveyors on fly ash. ■