Timothy

I would recommend to buy the components and then simply assemble them. I am not sure of anyone that builds cast flights but someone else may have heard of them.

You can buy the flights separate and weld them onto the pipe. There are many different ways to make the troughs and you can also use trough liners if wear is a problem.

Check out the Martin Sprocket site for more detailed info on Screw Conveyors.

http://www.martinsprocket.com/material.htm

You can also purchase "Screw Conveyor 101" by Michael P. Forcade which is a very detailed reference for design of screw conveyors.

Gary Blenkhorn ■

Timothy

Here is a link to the book if you want to order it.

http://www.amazon.com/exec/obidos/AS...6linkcode=xm2

Hopefully the link will work.

Gary ■

Cast screws are available usually not for conveyors but for extruders. I am not aware of cast flights. Perhaps someone else has some information on them. ■

It would hardly be economical or practical to make screw flights from scratch for a one-off screw conveyor or mixer. Assuming that the duty is a simple bulk transfer situation there is plenty of information on equipment selection in the CEMA book on the subject. There are also plenty of component suppliers of flights, screws, casing and other parts. For one not familiar with bulk behaviour there are various manufacturing and performance hazards that can incur operating expences well beyond the capital equipment cost if the plant does not work properly so it would be as well to secure good advice on the particular application before rushing in to make the equipment. For example, bying screw flights to weld onto a shaft seems a simple engineering function. However, straightening the auger to correct for weld distortion is more of a craft than it may appear and, if not done well, can result in bearing and seal problems or casing contact. The devil is in the detail when dealing with bulk solids.

As regards to mixing it is impossible to advise the best approach without knowing much more about the duty. If the plant is going to work for a long time it is likely to be false economy to skimp on the initial cost. Trouble-free performance is always best appreciated by those that have experienced the alternative, but it can be a costly learning excercise. ■