Mechanical Conveying

Flexible screw conveyors
Flexible screw conveyors are small diameter shaftless augers, 3" diameter to 6" diameter. Any larger, and they are no longer flexible. Flex screws can be economical and durable, if carefully designed and carefully applied. They are most useful on powders and granular materials with bulk densities below 80 lb/cf., and most durable on conveyor lengths less than 35 ft.


Case History

A principle advantage of flex screws is that there is no need for a bearing, and bearing seal, at the inlet end. Also, a flex screw can often convey at an angle steeper than a shafted conveyor, mostly because the shaftless spiral is run at a higher rpm. A flexible screw conveyor is run 100% full, and thus it often can deliver a higher rate than a rigid screw conveyor. Because it is full, there is little or no tumbling or agitation, and thus minimal attrition to the product. This also eliminates segregation during conveying.

Flexible screw conveyors don't like to run empty, so we are cautious about using them for small batch delivery, and where cross contamination to a subsequent batch is undesirable.

Small flex screws work well when dedicated to a single product; where the conveyor path is fairly short, and fairly straight (no sharp curves); and for materials that are not terribly sticky or cohesive. Examples are: calcium carbonate (grit, powder, air floated, micronized); clays of the same range; organic flours; grains, (raw, crushed, or milled); plastic pellets of most types; PVC dry blend compound; coarse pigments, dry or press cake; mixes (biscuit, cake, cookie); granular and powdered activated carbon PAC;

conveyor batching system

These conveyors can also be useful for short term use for low volume conveying of such products as abrasives (aluminum oxide, zirconium oxide), and abrasive minerals (silica and other sands), because they are simple and inexpensive to replace. In this use, a straight path is imperative.

We build flexible screw conveyors in 3,4, 5 , 6" nominal diameters, with UHMW PE or urethane housings, or in all stainless construction. We adapt the inlets to receive product from bag dump stations, bulk bag dispensers, portable bins and hoppers, rotary airlock valves, live bottom, stir bottom, or activated bins. The discharge (headbox) can be designed for discharge.

Shaftless Screw Conveyors
We build shaftless screw conveyors (essentially non-flexible) in 8, 10, and 12" diameters. These spirals can be from 3/8" to 1" thick, according to the application, and are suitable for coarse or highly variable materials, products that may knit or pack together, and abrasive materials. Larger augers are also useful for some damp products, or even sludges, that might adhere and co-rotate with a shafted auger.

CEMA Screw Conveyors
Applicon makes CEMA shafted screw conveyors in 6 to 14" diameters, usually with special features such as sanitary construction, extra heavy or special pitch flighting, thermal jacketed housing (trough).

High Angle Flexwall Belt Conveyor

Flexwall Belt and High Angle Conveyors
Flexwall belts have pleated rubber sidewalls bonded to the belt, to contain the bulk product on the belt. When equipped with bar cleats, C-cleats, or U-cleats, these conveyors can change direction up or down. For the right materials, these conveyors can even go from horizontal to vertical.

CEMA Trough Belt Conveyors
Troughing belts are simple, durable, and the least expensive way to convey bulk materials in a straight line, at inclines up to 30°.

Flat drag conveyors
Flat drag conveyors, for high rate of free flowing materials in a straight line path. Construction in mild, stainless or AR construction.

Tubular drag conveyors
Tubular drag conveyors, for completely closed conveyance in straight or multi-axis path, typically over distances less than 200 ft. Mild or stainless construction.

Belt conveyors and bucket elevators
Belt conveyors and bucket elevators provide the highest mass flow rates, to hundreds of tons per hour.