A screw conveyor is one of the most versatile and cost-effective mechanical conveyors for handling dry bulk materials. The conveyor provides enclosed transfer while moving materials horizontally, vertically, or at an incline and can deliver dry materials from one or more inlet points to one or more discharge points. The screw conveyor’s wide range of available configurations, components, and construction materials makes this piece of conveying equipment suitable for transferring even the most challenging dry bulk materials.
A screw conveyor consists of a screw mounted in an enclosed U-shaped trough (or tubular housing). The screw can have one or several sections, and each section consists can be mounted on a pipe or another transfer connection. At one end, the screw is connected to a rotating drive shaft, and the opposite end is connected to an end shaft. The screw is supported by bearings at the trough ends. If the screw conveyor is long enough to require more support, hanger bearings can be suspended from the top of the trough to support the screw at points between the screw sections.
Selecting a screw conveyor to handle your bulk material is really a matter of choosing the right combination of components and construction materials. While you’ll need to work closely with your conveyor supplier’s engineering department for technical advice during this process, here are some basics for making the right choices for handling your tough material in a screw conveyor.
Lion Bulk Handling is using screw conveyors on board of Self-Discharging Cement Carriers for the loading and unloading process, but also for truck loading and other bulk transfer possibilities. All our screw conveyor solutions are used for transferring fluidizable materials. Fluidizable materials are materials that tend to flow like liquids when aerated or mechanically agitated. Fluidizable materials can flow uncontrollably through a screw conveyor. Examples include alumina, Portland cement, powdered cocoa, fly ash, limestone dust, bentonite, and barite. To handle this kind of material, select a larger-diameter screw with a short pitch (that is, a short distance between flights), such as a short-pitch or half-pitch single flight screw. The short pitches in these screws will slow material flow through the conveyor. Running the screw conveyor at a slower speed will also reduce flooding. If your material will discharge to a downstream weighing device, you can use a double-flight short-pitch screw (which has two rows of flighting around the pipe) to better control the material’s flow and minimize surging, thus providing more uniform discharge to the weighing device.
Partnering with experts
Non-free-flowing materials, abrasive materials and toxic or explosive materials can be transferred by a screw conveyor as well. It is therefore very important to work closely with your screw conveyor supplier’s engineering department to ensure that the conveyor you choose will reliably handle your material. The supplier has years of experience designing conveyors to handle materials like yours. You’ll need to provide detailed information about your material’s characteristics and your desired conveying rate, expected conveyor usage, operating conditions, and other factors during this process. The supplier can run screw conveyor tests with your material to demonstrate that the conveyor components and construction materials can successfully handle your challenging material and meet your conveying goals.
Lion Bulk Handling
We are using for more than 50 years’ screw conveyors within our bulk handling systems. If you have any questions or would like to receive an offer for a screw conveyor, our engineering and experts are curious to know your bulk handling challenge. We are ready to assist you to help you to move forward. Let us know your bulk handling project at contact.