Mechanical Bulk Material Conveyors: Pros and Cons

Buyers of mechanical bulk material conveyors have a variety of technologies available to choose from. While no conveying technology yet invented is perfect in every respect, there are important strengths and weaknesses in each of the technologies currently available. Choosing the right conveyor is important for efficient and effective operations. This blog highlights the advantages and disadvantages of four common types of mechanical bulk material conveyors.

FLEXIBLE SCREW CONVEYORS

Consisting of a polyethylene (UHMW) tube in which a carbon or stainless steel auger rotates, flexible screw conveyors are perhaps the simplest and most cost-effective way to transfer materials at low to moderate rates.

Pros

• Relatively inexpensive, compared to other technologies
• Fully enclosed tube prevents product contamination and contains dust
• Flexible design allows routing around obstacles
• Supports batch-type production

Cons

• Can degrade product
• Abrasive materials can cause high wear
• Needs to be run with a full product load
• May separate or alter the proportions of mixed ingredients

AEROMECHANICAL CONVEYORS

Working on the principle of a fluidized airstream created by discs mounted on a rope, aeromechanical conveyors can move moderate amounts of material efficiently.

Pros

• Fully enclosed tube prevents product contamination and contains dust
• Can convey at any angle from 0 – 90 degrees
• No separation of mixtures
• Low energy requirements

Cons

• Maintenance costs can be higher
• Cannot start/stop under a full load
• Requires a controlled feed

BUCKET ELEVATORS

Used to transfer materials horizontally, vertically, or in an inclined plane, bucket elevators consist of a series of buckets mounted onto a chain or belt.

Pros

• Can transfer large capacities of material
• Good designs can gently handle product and prevent degradation. Enclosed designs contain dust.
• Does not separate mixed ingredients
• Can handle moist or wet materials
• Can handle a wide variety of material forms, from sub-micron powders to irregular shapes

Cons

• Metal drive chains may need periodic re-tensioning
• Drive belts and chains may need periodic replacement
• Buckets and chains may undergo wear and tear

TUBULAR DRAG CONVEYORS

These conveyors use discs attached to a metal chain to pull wet or dry material through the conveyor to the discharge point.

Pros

• Conveyor is self-loading
• Can accommodate multiple loading and discharge points
• Enclosed tube contains product and dust
• Can convey at different angles

Cons

• Abrasive materials can cause wear
• Product may deposit and build up on tube walls
• May degrade fragile materials
• Higher energy costs

When choosing from these four types of mechanical bulk material conveyors, buyers will want to consider the relative advantages and disadvantages of each for their particular operation and application. Making the right choice will result in improved operations and reduced costs, as well as ensuring a good match with other equipment and systems.

If you are seeking guidance and support for choosing a mechanical bulk material conveyor for your operation, UniTrak can help. We have over 45 years’ experience in helping companies the world over to solve their bulk material conveying challenges. Our equipment portfolio features conveyors purpose-built to serve high-care, severe service, critical service, and cleanable service applications. To speak with one of our application experts, please contact our sales team directly.