Gear Units - Calculation and Selection - ATLANTA …

1 gear Units - Calculation and Selection The values given in the load table are based on uniform, smooth servo-operation. Since, in practice, the applications are very diverse, it is essential to consider the given condi tions by using the appropriate factors S, KA and bB (see symbols). The maximum oil-sump temperature of 80 C should not be exceeded. Formulas for Determining Power and Torque Data: Safety Coefficient S. The Safety Coefficient should be allowed for according to a = [m/s ]. tb experience (S = to ). Fu = m g + m a (for lifting axle) [N]. Symbols Fu = m g + m a (for driving axle) [N] a = Acceleration or Retardation (m/s ). Fu d bB = Operating Time Factor T2req. = [Nm] d = Pinion Pitch-Circle Diameter (mm).

2 2000 g = Acceleration Due to Gravity ( ). m = Mass (kg). n2 = 60000 (rpm) [rpm] n1 = Gearbox Input rpm (rpm). d . n2 = Gearbox Output rpm (rpm). n1 tb = Acceleration Time (s). igear =. n2 i = gear Ratios (--). T2table = Travelling/Lifting Speed (m/s). [Nm] Fu = Peripheral Force at the Pinion (N). KA S bB. KA = Load Factor (--). P1 = Gearbox Input Power (kW). Condition T2perm. > T2req. must be fulfilled. S = Safety Coefficient (--). T2req. n2 T2 = Gearbox Output Torque (Nm). P1req. = [kW] = Gearbox Efficiency (--). 9550 . = Coefficient of Friction (--). Load Factor KA = Drive Type of load from the machines to be driven uniform medium shocks heavy shocks uniform light shocks medium shocks Operating Time Factor bB.

3 Operating time 4 8 h 8 12 h >12 h Operating time factor GF 2 Dimensions in mm 1/2012. gear Units - Calculation and Selection Calculating Example Your Calculation Values Given Values Given Travelling Operation x Lifting Operation Travelling Operation Lifting Operation Mass to be Moved m = 300 kg Mass to be Moved m = kg Speed v = m/s Speed v = m/s Acceleration Time tb = s Acceleration Time tb = s Acceleration Due to Gravity g = m/s Acceleration Due to Gravity g = m/s . Coefficient of Friction = Coefficient of Friction = Pitch-Circle Dia. of Pinion d = mm Pitch-Circle Dia. of Pinion d = mm Load Factor KA = Load Factor KA = Operation Time Factor bB = Operation Time Factor bB = Safety Coefficient S = Safety Coefficient S = Motor rpm n1 = 3000 rpm Motor rpm n1 = rpm Motor Type Motor Type Motor Manutacturer Motor Manutacturer Calculation Process Results Calculation Process Results a = a = = 4 m/s a = a = = m/s.

4 Tb tb Fu = m g+m a Fu = 300 +300 4 = 4,143 N Fu = m g+m a Fu = = N. only Travelling Operation Fu = m g +m a Fu = m g +m a Fu = = N. F d T2erf. = u T2erf. = 4143 = 132 Nm T2erf. = Fu d T2erf. = = Nm 2000 2000 2000. n2 = 60,000 n2 = 60000 = 324 rpm n2 = 60000 n2 = 60000 = rpm d d . n 3000. iGetr. = 1 iGetr. = iGetr. = n1 iGetr. = n2 325 n2. Permissible gear Torque T2table see page GB-13 Permissible gear Torque T2table see page .. assumed 58_5_09 with T2 =280 Nm at 3,000 rpm T2 Table T 280 T2zul. = T2zul. = = Nm T2zul. = 2 Table T2zul. = = 155 Nm KA S bB. KA S bB Condition Condition T2zul. > T2erf = Nm > Nm = fulfilled T2zul. > T2erf = 155 Nm > 132 Nm = fulfilled T2erf n2. P1erf = P1erf = = KW. T n 132 324 9550.

5 P1erf = 2erf 2 P1erf = = KW. 9550 9550 Result: gear 58_5_09 Page GB-6. 1/2012 Dimensions in mm GF 3.