Effective Strategies for Dust Control and Material Management at Conveyor Transfer Points
Covering the skirtboard on a conveyor belt with a steel or fabric system whenever possible is crucial for controlling dust at transfer points. All skirtboards should have some form of enclosure, unless there are specific reasons not to. These coverings create a plenum that allows dust to settle and reduces air movement. A spacious plenum effectively manages the dust clouds generated during material transfer.
Installing a well-designed skirtboard cover significantly reduces air movement and thereby minimizes dust escaping from transfer points. These covers also prevent fugitive materials from spilling over the skirtboard. Occasionally, material lumps can bounce off the belt if there's no cover to contain them upon entry through the loading chute.
The Conveyor Equipment Manufacturers Association (CEMA) recommends that skirtboard covers slope downward from the loading chute to the skirtboard, allowing for smoother material flow and preventing jams. CEMA's guidelines, outlined in Belt Conveyors for Bulk Materials, Sixth Edition, specify minimum skirtboard heights and belt widths based on lump size. Standard practice dictates that skirt dimensions should be at least 2.5 times the width and height of the largest conveyed lumps to prevent jams and ensure sufficient plenum space for dust settlement.
Skirtboard covers typically consist of a flat roof spanning between the two skirtboards, unlike the semicircular "hoods" found on some conveyor belts. Steel is generally preferred for these covers because it can be securely clamped onto the skirtboards and facilitates easier inspection and maintenance. Fabric or rubber is commonly used to connect vibrating equipment to stationary chutes or skirtboards.
Steel roofs should be designed to support the weight of a worker, whereas fabric covers should include warnings against stepping on them due to their inability to bear weight. In both cases, covers should feature openings that allow workers to service and inspect the conveyor. These openings must be equipped with doors to prevent the escape of air and materials.