NMRV Worm Gearbox Selection Guide – How to Choose the Right Model

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NMRV Worm Gearbox – 4-Step Selection Guide

Step 1 – Determine your rati

Ratio = Motor RPM ÷ Desired Output RPM

Example: 1,400 RPM motor, need 35 RPM output → 1,400 ÷ 35 = 40:1

Step 2 – Calculate output torque
Output Torque (Nm) = Motor Torque × Ratio × Efficiency

Always include efficiency in your calculation. A 60:1 worm gearbox at 55% efficiency delivers much

 less torque than the ratio alone suggests

Step 3 – Apply service factor

Load Type	Service Factor
Uniform	1.0
Moderate shock	1.25 – 1.50
Heavy shock	1.75 – 2.0

Step 4- Matching frame dimensions for NMRV turbine gearbox

Frame	Typical Motor	Best For
NMRV030	0.25-0.37 kW	Light conveyor, small agitator
NMRV040	0.37-0.75 kW	Gate automation, light conveyor
NMRV050	0.75-2.2 kW	Cement mixer, conveyor drive
NMRV110	4-7.5 kW	Heavy conveyor, large agitator