Transmission Gear Shaft Custom-Made with Gear Milling and Gear Hobbing

1) Description of Girth Gear

The girth gear is the larger component in a gear pair, typically functioning as the driven wheel. Its primary role is to reduce output rotational speed while simultaneously increasing output torque, thereby providing substantial power to the equipment.

2) Working Principle

The driven pinion drives the ring gear. According to the gear ratio (number of teeth on the ring gear divided by number of teeth on the pinion), the pinion must rotate multiple times before the ring gear completes a single revolution. This achieves a reduction in rotational speed and a multiplication of torque.

3) Feature of Girth Gear

Large dimensions, substantial weight, and high inertia.

• Typically constructed from high-strength materials such as cast steel or forged steel.
• Often employs a radial plate structure to minimise weight.
• Teeth profiles commonly feature helical or herringbone cuts for smooth load transmission.

4) Advantage of Girth Gear

• Provides powerful deceleration and torque multiplication.
• Delivers stable and reliable transmission ratios.
• High load capacity with extended service life.

5) Application

Primarily used in equipment requiring low-speed, heavy-duty power transmission:

• Industrial gearboxes
• Mining machinery (crushers, ball mills)
• Wind turbine gearboxes
• Marine propulsion systems
• Heavy-duty lifting equipment

Technical Specifications