Planetary gearboxes are used because they can transmit very high torque in a compact and lightweight design. The load is shared among multiple gears, which increases strength, efficiency, and service life. They also provide smooth operation, low backlash, and high precision, making them ideal for heavy-duty and servo-driven production machines. This is why they are widely used in extrusion, cranes, mixers, wind turbines, and CNC systems.

1. Injection Molding Machines

Application: Screw drive & clamping unit
Why planetary gearbox:

• Very high torque at low speed
• Precise speed control for plastic flow
• Compact installation near screw motor

Typical Gearbox Models:

• Bonfiglioli 300 Series
• Apex Dynamics AB / AF Series
• Neugart PLE / PLQE Series

Example:

• 180–450 ton injection molding machine using servo motor + planetary gearbox for screw rotation.

2. Extrusion Machines (Plastic, Rubber, Aluminum)

Application: Extruder screw drive
Why:

• Continuous heavy load
• High torque, low RPM
• Excellent heat and load resistance

Typical Models:

• Flender PLANUREX 2
• SEW-Eurodrive P Series (Industrial Planetary)
• Bonfiglioli GP / HDP Series

Example:

• PVC pipe extrusion line
• Rubber profile extrusion plant

3. Rolling Mills & Steel Processing Lines

Application: Roller drive, coiler, uncoiler
Why:

• Shock load resistance
• High power transmission
• Long service life

Typical Models:

• Flender PLANUREX 3
• David Brown PX Series
• Rossi EP / E Series

Example:

• Rebar rolling mill
• Sheet metal processing line

4. Concrete & Batching Plant Equipment

Application:

• Pan mixers
• Twin-shaft mixers
• Conveyor drives

Why:

• Very high torque
• Compact vertical mounting
• Handles dusty & harsh environments

Typical Models:

• Bonfiglioli 300M Series
• SEW P Series
• Rossi GEP Series

Example:

• Concrete batching plant pan mixer
• PHC pile production mixer (commonly used)

5. Wind Turbines

Application: Main gearbox between rotor & generator
Why:

• Multistage speed increase
• Load sharing among gears
• Handles fluctuating wind loads

Typical Models:

• Winergy Planetary Gearboxes
• ZF Wind Power Gearboxes
• Moventas Planetary Gear Systems

Example:

• 1.5 MW–3 MW horizontal axis wind turbine

6. Cranes, Hoists & Winches

Application:

• Hoisting mechanism
• Slewing drive

Why:

• High torque in compact size
• Smooth load lifting
• High safety & reliability

Typical Models:

• Bonfiglioli 300C Series
• SEW Hoist Gear Units (PH / P Series)
• Rossi EP Series

Example:

• Overhead crane hoist
• Shipyard winch system

7. Conveyor Systems (Heavy-Duty)

Application: Long belt conveyors, mining conveyors
Why:

• High torque at low speed
• Energy efficiency
• Compact inline mounting

Typical Models:

• SEW P Series
• Nord MAXXDRIVE Planetary
• Bonfiglioli HDP Series

Example:

• Cement plant raw material conveyor
• Mining belt conveyor

8. CNC Machines & Automation Systems

Application: Axis drives (X, Y, Z), rotary tables
Why:

• Low backlash
• High positional accuracy
• Smooth servo response

Typical Precision Models:

• Apex Dynamics AB / AE Series
• Neugart PLE / PLS Series
• Wittenstein Alpha TP / SP Series

Example:

• CNC milling machine
• Robotic arm joint drive