Slider and Roller Bed Belt Conveyors

Slider Bed Belt Conveyor

Belt conveyor consists of two or more pulleys with a continuous loop of material, known as the conveyor belt, being driven around the pulleys.  Generally speaking, one of the pulleys is powered, moving the belt and the material being conveyed on the belt forward.  The powered pulley is referred to as the drive pulley, while the unpowered pulleys are referred to as idle pulleys.  While there are two main industrial classes of belt conveyor types – those utilized for general material handling, such as those that move cartons, totes and pallets, and those utilized for bulk material handling, such as those that move bulk materials such as agricultural grains, coal and produce – generally speaking, companies that provide general material handling belt conveyors do not provide bulk material handling conveyors. 

Belting typically consists of one or more layers of material.  Many belts utilized for general material handling purposes are comprised of two layers – the “carcass”, which is the under layer of material that provides the belt’s linear stability, strength and shape, and the “cover”, which is the over layer of material that provides the belt’s carrying or contact surface for the materials being handled.  The carcass can often be comprised of cotton material or plastic web/mesh.  The cover can be any number of a variety of materials based on the intended use for the belt.  Some of the more common types of cover are different rubber or plastic compounds.  Belting is either laced and pinned together at the seam/splice or vulcanized (hot welded) to provide a seamless splice.

Roller Bed Belt Conveyor

General material handling belt conveyors are typically comprised of one of two designs – roller bed, in which the belt is supported and carried by rollers, or slider bed, in which the belt is supported and carried over the continuous metal bed surface or a series of metal pans.  Roller bed design allows for longer runs of conveyor due to the lower coefficient of friction experienced between the weight of the product on the belt and the free-turning rollers (as compared to the drag created between the belt and the static bed surface and/or metal pans).

Due to their versatility and least expensive price, belt conveyors are the most commonly used and applied powered conveyors.  Because product is carried directly on the belt surface, both regular and irregular shaped products, large and small, light and heavy, are all conveyed successfully.  They are commonly used to convey items with irregular bottom surfaces, small items that might otherwise fall between the rollers for conveyors of different design, bags that might sag between the rollers for conveyors of different design, and products with a “frame” type, minimum contact, bottom surface design.  Belt conveyors are typically used to transport product in a straight line and/or through changes in elevation.  While belt conveyors are used for static accumulation of product in some applications, the implementation of controls logic can allow for them to also be used in dynamic, indexing accumulation applications as well.