Conveying Angle
Now that I've seen it I actually prefer your 'angle of ascent' description.
You can find the required information, near enough, in most belt manufacturers design handbooks which can be downloaded for free. Fenner Dunlop, Yokohama, Bando, Goodyear, Phoenix for starters.
CEMA handbook is very comprehensive but uses yesteryear's units. MHEA is a metric abridgment of CEMA and DIN is, quite frankly, a unique distraction, excellent in its own way but not much use even though it is the only Standard: the rest are simply recommended practices.
If you just want the Angle of Ascent you should stick with the free downloads and not shell out on non-committing recommended practices. All the figures are empirical and you will be very lucky indeed to find the exact angle. Just as lucky as you would be to maintain product consistency. If your product closely resembles the specification then you will be one of the lucky practitioners. ■
John Gateley johngateley@hotmail.com www.the-credible-bulk.com
Re: Maximum Angle Of Ascent
Originally Posted by johngateley
CEMA handbook is very comprehensive ... MHEA is .. quite frankly, a unique distraction...
If you just want the Angle of Ascent you should stick with the free downloads ... All the figures are empirical and you will be very lucky indeed to find the exact angle. Just as lucky as you would be to maintain product consistency. If your product closely resembles the specification then you will be one of the lucky practitioners.
Hi John, thank you for your reply, if my low knowledge of the English language does not betray me, you're saying that it is very easy to find tables with theoretical data, but it is very difficult to predict whether the material I transport will behave as indicated in the tables: is that what you want me explain it to me?
You believe that those directions are useless or you're just saying that the different conditions of humidity, particle size and specific gravity of the same product can vary a little the values of those tables?
In any case, I'd be happy to download these books, but I've surfed all the websites of the companies that you have mentioned, but I have not found the link to download the manuals or tables: would you be so kind as to leave all of the direct links here? (the only manual I consulted this morning is that of the Phoenix but what I did not find anything useful for this case).
PS: please leave here also the CEMA handbook and MHEA handbook links.
Many thanks ■
Maximum Angle Of Ascent
Hi,
I agree with you, ceramic and porcelain are very good and useful products for manufacturing of conveyors belts for clay. And really it’s very difficult to find some exact angle of slope for bulk materials. For this you have to calculate as per your requirement because there is no direct way to find out the angle of slope. ■
Re: Maximum Angle Of Ascent
Hello,
The conveyor maximum inclination to convey particular material has to satisfy following 3 conditions:
1) Material should not slide on belt. This means conveyor inclination delta should be less than tan-inverse-friction coefficient between material and belt.
2) Material should not slide on its own surface. This means conveyor inclination delta should be less than tan-inverse-friction coefficient between material and material.
3) Material should not roll back.
Material repose angle signifies friction angle material to material, for stationary situation.
Material surcharge angle signifies friction angle material to material, for vibrating situation, as happening during belt conveying. Surcharge angle is less than repose angle by certain magnitude, as observed since long time, and mentioned in various literature. More agitation (vibration) of material (higher speed and higher sag percentage) tends to reduce surcharge angle marginally and thereby allowable inclination.
For practical solution, refer conveyor design literature, which mentions allowable maximum inclination for routine conveyors. For example Dunlop (UK) mentions this data for about 180 materials, IS mentions this data for about 480 materials, US literature mentions for about 350 materials, German belt manufacturer’s catalogue also mentions and so on. These literatures generally mention allowable inclination for salt as dry fine or as dry coarse, etc.
Conveyor inclination beyond actual material’s sustaining ability, can result into non-usable conveyor. So cautious designers, generally keep inclination 10% to 15% lower than the maximum listed inclination value. For non-listed use the data for listed material which has similar physical characteristics.
Ishwar G. Mulani
Author of Book : Engineering Science And Application Design For Belt Conveyors (new print November, 2012).
Author of Book : Belt Feeder Design And Hopper Bin Silo.
Advisor / Consultant for Bulk Material Handling System & Issues.
Pune, India.
Tel.: 0091 (0)20 25871916
Email: conveyor.ishwar.mulani@gmail.com
Website: www.conveyor.ishwarmulani.com ■
Maximum Angle of Ascent
How to know the maximum angle of ascent of a bulk material (salt in this case)
Hello to all,
we are specialized in the manufacture of conveyor belts for clay, clay -sized , high clay and crushed atomized clay , (in the field of ceramic and porcelain) these products have a great experience and with the time we have had feedback with our experiences.
Sometimes , however, our costumers require us conveyors for bulk materials other than clay, in these cases we do not have references based on the expertise to determine the angle of maximum lift with smooth rubber belt (or belt with a chevron "V").
I found some tables showing the angle of repose of some materials , but I did not find a table or a formula that indicates the angle of ascent.
How is it possible to know the angle of ascent (on the conveyor belt ) of a material ?
In this case, I need to know the angle of ascent SAL with size 15/20mm and 15% humidity and SAL with size 4/5mm and 15% humidity , but I would like to understand how to find the angle of slope for all bulk materials .
Can you help me ? ■