Screw Selection

There are many reasons & applications which require variation to standard screw conveyors. These are just some of the factors & conditions that will influence the design & construction of a screw conveyor:

• What material will you be conveying?
• What are the material characteristics?
• What is the bulk density of the material?
• What through put capacity is the screw to be designed for and at what housing loading?
• Where will the material be coming from?
• Is the screw to be a feeder or a conveyor?
• Is the screw horizontal, incline or vertical?
• Is the screw reversing?
• How long will the screw be, centerline of the inlet to the centerline of the discharge?
• Are intermediate hanger bearings for the screw acceptable?
• Housing construction information:
  • Material of construction
  • Dust tight construction
  • Pressure tight construction (i.e. Will the housing have to hold pressure)
  • Will the housing require a "code stamp"?
  • Will the equipment be in wash down service?
  • Hinged covers?
  • Tubular or "u" trough housing?
  • Type of shaft seals
  • Food grade polish
  • Welding requirements
  • How is the housing supported, etc.
• What is the inlet size that we are connecting to and how many inlets are there?
• What is the discharge size that we are to connect to?
• Is the discharge a drop out, injector style or positive feed?
• Is there more than one discharge called out, and do they have slide gates?
• What style are the slide gates and how are they operated?
• Is the screw service continuos, 8 hr a day, 24 hr a day, batching, intermittent etc.?
• If there is more than one screw to a housing, how many drives?
• Is the screw to be portable?
• Will the screw be required to dewater or drain product?
• Will the screw be required to mix product while conveying?
• Will the product be abrasive?
• What material of construction in product contact?
• What type of welding in product contact?
• What finish or polish is required in product contact?

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