How to calculate the power and speed ratio of a gearbox in a reducer

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What equipment is the reducer used for in order to determine the safety factor SF (SF=rated power of the reducer divided by motor power), installation form (orthogonal axis, parallel axis, output hollow shaft key, output hollow shaft locking plate, etc.), etc

1.Speed ratio (i)=motor input speed ÷ reducer output speed

Example: 4-pole motor at 1450 r/min, need output 25 r/min

i = 1450 ÷ 25 = 58:1

Select the closest standard ratio from K Series range (e.g. 57.85 or 60.28).

2、 Torque Calculation

Output torque T ₂=9550 × P × i × η ÷ n ₁

3.Power Matching

Required motor power P=T ₂ × n ₂ ÷ (9550 × η)

Example: Need 1,500 N·m at 25 r/min output

P = 1500 × 25 ÷ (9550 × 0.95) = 4.13 kW → Select 4kW or 5.5kW motor

4.Service Factor

Always apply service factor (SF) based on load type and daily operation:

Load Type Daily Hours SF

Uniform 8-10 hrs 1.0 – 1.2

Medium Shock 8-10 hrs 1.2 – 1.5

Heavy Shock8-10 hrs1.5 – 1.8