Nema 34 Planetary Gearbox

NEMA 34 Planetary Gearboxes

A NEMA 34 planetary gearbox mounts to stepper motors with a 3.4-inch (≈86 mm) square flange. Inside, a sun-and-planet gear set provides reduction to lower output speed and multiply torque according to the selected ratio (within gearbox efficiency and rated limits).

Selection considerations

• Ratio: Choose a reduction ratio that meets the target output RPM while keeping motor speed within its specified operating range.
• Rated torque: Check continuous and peak torque ratings against the real duty cycle, including starts, stops, and acceleration.
• Backlash: Select a backlash grade that matches the positioning requirement for the axis.
• Interfaces: Verify flange fit, pilot diameter, shaft coupling, and output shaft dimensions before ordering.
• Loads and environment: Confirm radial/axial load limits, lubrication type, operating temperature range, and mounting orientation guidance.
• Common pitfall: If the output shaft carries an overhung load, confirm the allowable load at the required distance from the face—this often determines gearbox life.

Typical applications

NEMA 34 planetary gearboxes are used in industrial automation, CNC axes and mechanisms, robotics/actuators, 3D-printer drives, and packaging equipment where compact reduction is needed. Final selection should account for load inertia, duty cycle, mounting space, and the external loads applied to the output shaft.