Leornoj,
A company I used to work for 49 years ago used to quite successfully use Super-Flo conveyors for handling Sugar , they are a drag conveyor running in a screw conveyor trough, they have nylon flights and can be fitted with UHMWPE Glissades for the chains, they are self cleaning.
See link http://www.screwconveyor.com/engineering-product-s...
You could also look at changing the type of bearing in the hanger to a sealed roller bearing.
Good Luck,
B.E.

You are judged not by what you know, but by what you can do.

Hi Berkshire,

Thank you for replying to my concern. Super-flo conveyor is a great alternative. However, I want to eliminate possible non magnetic sediment such as UHMW or any plastic materials that may compromise the food safety. Is there any substitute materials for nylon flights and UHMWPE Glissades for chains a that can be detected by our metal detector and can be removed by magnets.

Also, I am contemplating to used split type roller bearing for hangers. But i need to have more space in the hanger bearing landings in order fit the said bearing and the result will be a wider gap between ribbon that may cause non conveyance of the sugar material.

Your suggestion will be greatly appreciated.

Thank you.

Leonhoj

leornhoj,
I do not know who's conveyors you are using? The company I used to work for, was a partner with Screw conveyor corp., of Hammond Indiana. These people also make the Super-flo conveyors I mentioned. There is another company in Texas KWS inc., that makes a line of screw conveyors and associated parts : http://www.norfolkbearings.com/products/kws/KWS-CA... These may be of some assistance .
The problem with non metallic components such as Nylon or UHMW as you are well aware, is that they cannot be screened out by a magnet. Whilst these materials can be screened out earlier in the refining system by melting the sugar and running it through filters, if the sugar is fully refined you cannot do much about that. It should be noted that if the conveyors are properly installed, and run in, the amount of plastic scraped off will be miniscule.
Also thinking about the fact that you say you need more width for roller bearings for the most part depending upon you trough loading you should not have a problem with non conveyance until the conveyor is almost empty, you may be better served by ball bearing hangers with dust seals. They are somewhat narrower than the roller bearings, however if you have the flat formed hanger bearings with a plain bearing insert, you would have to change them to a tubular bearing support. The only other suggestion for metal dust, is one you should already have in place which is a set of Alcomax or similar magnets on the discharge chutes.
B.E.

You are judged not by what you know, but by what you can do.

Hi Berkshire,

I will consider ball bearing hangers with dust seals. Your suggestions help me a lot.

Thank you.

Regards,

Leornhoj