Timing Belts Catalogue

152Calculation ExamplesCalculation ExamplesCalculation ExamplesStep e: Calculation/control of timingbelt widthThe formula to check the belt width is:Pmech2,4wtb = == 12,5mm< 30mmt * P 12*0,01596especThe minimum required belt width is12.5 mm. A look at the catalogue pagefor T10 timing belt shows that the nextstandard width is 16 mm.Result step 5:Timing belt width 16 mmStep f: Calculation of the preliminarycentre-centre distanceAccording to the given data thecentre-centre distance should be 500 to600 mmStep g: Calculation of the belt lengthDue to the fact the centre-centre distanceis given as a range (500 to 600 mm,550 mm is assumed), it is sufficient todetermine the belt length only approximately:ltb,ap= 2* CC +210= 2*550 +22p ⎛ t − t ⎞⎜ ⎟CC ⎝ 2π⎠2 1( t + t ) + [ mm]12210 ⎛ 40 − 25 ⎞⎜ ⎟550 ⎝ 2π⎠( 25 + 40) += 1425,4mmIn accordance with the catalogue pagesof the T10 moulded timing belts, thenext standard length is 1420 mm.Result step 7:belt length 1420 mm2) Timing belt for a conveyorGiven data:Goods to convey:Weight: 90 kgMaximum number of pieces on the conveyor: 10Conveyor:Goods are supported by two timing beltCentre-centre distance: 10 metres as exactly as possiblePulley diameter: approx. . 200 mmConveying velocity: 0.3 m/sAll pulleys of same sizeSliding support of timing belt (coefficient of friction m = 0.3)Inclined system with angle of 15°Other:Acceleration: 1 m/s 2Mechanical efficiency of the system is highDelivery time as short as possibleStep a: Calculation of present forcesThe total load on the conveyor is 10* 90 kg = 900 kg.According to following formula the forces are calculated:F = ( Fac + Frem+ Fincl)*(1,05 ÷ 1,15)Acceleration force:mF ac900Motion resistance:Climbing resistance:In total[ N]= m* a [ N] = 900kg*1 N2s=m= m* g * µ *cosα[ N] = 900kg*9,81 *0,3*cos 15°= N2F rem2559smF incl= m* g *sinα= 22852s[ N] = 900kg*9,81 *sin15°N[ N] = ( 900N+ 2559N+ 2285N) *1,05 NF = ( Fac + Frem+ Fincl)*(1,05 ÷ 1,15)= 5744The load is supported by two belts, so the total force for a singlebelt is 2872 N.Result step 1: F = 2872 NCopyright © Ammeraal Beltech 2006Final result:The calculated timing belt is a mouldedbelt type T10 with 1420 mmlength and 16 mm wide.