Best conveyor for highly abrasive material

[dvvndrpl]

Hello,
I have been scouring the internet to no avail for an answer to my question. Hoping there's someone out there who can help me.
I work at a fiberglass manufacturing plant and am trying to specify a conveyor to transport glass cullet, a highly abrasive scrap material, from one area of our plant to another. Cullet is basically granular glass, much like sand but with sharp edges instead of round particles. We currently use a combination of manual (i.e. skid steer) and dense phase pneumatic transport to move this material, but we’re trying to get to a more automated system.
I have several salesmen trying to sell us tubular drag conveyors to do this job, but we have concerns with abrasive wear with this technology. The advantage of tubular drag systems is that they would allow us to easily install multiple pick-up and drop-off points, they are easy to route through our congested plant, and they do not require compressed air. If wear is not a factor they seem like a great solution for our situation.
I’m wondering if anyone could provide me with some insight on how well a tubular drag conveyor would hold up to glass cullet. The conveyor being proposed consists of cast iron discs being carried by forged chain inside of Ø4” induction hardened steel pipe. The conveyor travels approximately 300 ft horizontally and 65 ft vertically.
I’m also wondering if anyone would have some input on the best system for carrying this material would be, all else being equal. My gut feeling is that a belted conveyor with bucket elevators for the vertical sections would probably give the least abrasive wear, however this type of system would have considerably more components and be much more difficult to install due to tight space constraints. Are there other options that I should consider?
Any help would be greatly appreciated! Thanks!

 

[micalbrch]

First I must confess that I do not have any practical experience. I know what a tubular drag conveyor is and the big andvantage is really its flexibility and the multiple pick-up and drop-off points. But you want to handle not a typical bulk material but some very abrasive and sharp-edged material. A tubular drag conveyor does not look like the best possible solution for me, considering wear resistance. What about a through chain conveyor?

 

[maripali]

I'd prefer trough belt with tracks conveyor as the choice of the belt materials is really various.
And lifting angle is still in range.

 

[dvd]

The more cullet that can ride over cullet instead of tube surface, the better. If you are sizing the tubular drag conveyor based on your mass flow requirements, you are probably filling the conveyor tube to some recommended filling degree and running at the manufacturer's recommended speed. If you get a bigger diameter tubular conveyor and run it full and more slowly, then you won't have as much cullet in contact with tube surface, and the surface speed will be lower resulting in a lower wear rate.

You also do not state the path required. If you only need a straight line, then an en-masse conveyor might serve you well - research those a little. Not sure if you could get the lift you need in that short of run but an elevator and en-masse conveyor combination may work.

If your path is short a belt will wear out fairly quickly. The differential velocity of material contacting the belt is what wears the belt, and a short belt sees lots of revolutions compared to a longer belt. When you drop cullet onto the belt it causes wear. Material moving along at the same speed as the belt is not the major cause of wear. If you make a short conveyor which accelerates the cullet up to the belt speed of your main conveyor and gently places it on the main conveyor, you might have some luck with a troughed belt conveyor. The short conveyor would experience high belt wear and should be designed to allow for easy belt changes. If the cullet has fines in it that could be separated it may also be of use to deposit the fines on the belt before the large particles, but if the cullet is wet it probably is not easily sifted.