Facts & Figures Book - KPI-JCI

. Material characteristics can affect other elements ofconveyor selection.• Heavier material or large lumps may require more HP,heavier belt, closer idler spacing and impact idlers atfeed points• Abrasiveness may require wear liners or special rubbercompositions• Moisture may require steeper hopper sides, wider belts,anti-buildup return idlers and special belt wipers• Dust content may require special discharge hoods andchutes, slower belt speeds and hood covers• Sharp materials may require impact idlers, wear liners,special belt and plate feeder• Lightweight materials may require wider belts and lesshorsepowerc. Conveyor BeltA conveyor belt consists of three elements: Top cover,carcass and bottom cover.The belt carcass carries the tension forces necessary instarting and moving the loaded belt, absorbs the impactenergy of material loading, and provides the necessarystability for proper alignment, and load support overidlers, under all operating conditions.Because the primary function of the cover is to protectthe carcass, it must resist the wearing effects of abrasionand gouging, which vary according to the type of materialconveyed. The top cover will generally be thicker than thebottom cover because the concentration of wear is usuallyon the top or carrying side.The belt is rated in terms of “maximum recommendedoperating tension” pounds per inch of width (PIW). ThePIW of the fabric used in the belt is multiplied by the numberof plies in the construction of the belt to determine thetotal PIW rating of the belt.Material Handling181