MINIMUM PULLEY Carcass Thickness (mm) Reinforcement Material Cotton/ Cotton Nylon/ Nylon Polyester/ Nylon From To From To From To DIAMETERS FOR BELT CONVEYORS Recommended Minimum Pulley Diameter (mm) Percentage of “ RMBT” *used Over 60 % Over 30 % Up to 30 % Up to 100 % Up to 60 % Type of Pulley A B C A B C A B C ­ 1.2 ­ 1.1 ­ 0.9 1.3 1.5 1.2 1.3 1.0 1.1 1.6 2.0 1.4 1.7 1.2 1.4 2.1 2.5 1.8 2.2 1.5 1.8 100 125 160 200 ­ ­ 100 ­ 125 100 160 125 ­ ­ ­ ­ ­ ­ 100 ­ ­ ­ ­ ­ 125 100 ­ 100 100 ­ 160 125 100 125 125 100 2.6 3.1 2.3 2.7 1.9 2.3 3.2 3.9 2.8 3.5 2.4 2.9 4.0 5.0 3.6 4.4 3.0 3.7 5.1 6.2 4.5 5.5 3.8 4.6 250 315 400 500 200 250 315 400 160 200 250 315 200 250 315 400 160 125 160 160 125 200 160 200 200 160 250 200 250 250 200 315 250 315 315 250 6.3 7.8 5.6 7.0 4.7 5.8 7.9 10.0 7.1 8.8 5.9 7.4 10.1 12.5 8.9 11.1 7.5 9.2 12.6 15.6 11.2 13.8 9.3 11.5 630 800 1000 1250 500 630 800 1000 400 500 630 800 500 630 800 1000 400 315 400 400 315 500 400 500 500 400 630 500 630 630 500 800 630 800 800 630 15.7 17.5 13.9 15.5 11.6 12.9 17.6 20.0 15.6 17.7 13.0 14.8 ­ ­ 17.8 20.0 14.9 16.6 ­ ­ ­ ­ 16.7 18.5 1400 1600 1800 2000 1250 1250 1400 1600 1000 1000 1250 1250 1250 1250 1400 1600 1000 800 1000 800 1250 1000 1250 1000 1000 1000 800 1000 1000 800 1250 1250 1000 1250 1250 1000 * RMBT­ Recommended Maximum Belt Tension A. Driving pulleys and pulleys exposed to high belt tension­ e.g. main driving pulley on the head or tail; delivery pulleys under full tension; loop pulleys in the tripper; terminal head pulleys in the case of tail driving etc. B. Snub pulleys in the return run under lower belt tension­ e.g. terminal tail pulleys in the case of head driving; terminal head pulleys for downhill conveying, if the terminal tail pulley is braked; snub and bend pulleys in the take­up devices. C. Bend pulleys, for a change of direction of the belt of less than 30º.
NORTHLAND RUBBER MILLS REGISTERED OFFICE : NORTHLAND HOUSE, 8­CENTRAL MARKET, PUNJABI BAGH (W), NEW DELHI­110026, INDIA Tel : 0091 11 25224471, 25226928 Fax : 0091 11 25222717, www.northlandrubbermills.com WORKS : 20 TH /5­6, MILE STONE, G.T. ROAD, RAI – 131029, SONEPAT, INDIA. Tel. 0091 130 2366246, 2366286 Fax : 0091 130 2366640