Heavy-Duty Girth Gears (Ring Gears) for Mills and Kilns

Product Description

Yile Machinery is a leading manufacturer of custom girth gears, the critical component for driving large-scale rotating equipment. Engineered for maximum durability and service life, our girth gears are the trusted choice for the world's most demanding industries, including cement production, mining, and mineral processing.

Manufacturing Segmented Girth Gears: A Process of Precision

Due to their immense size, girth gears are typically manufactured in two, four, or more segments for ease of transportation and installation. The success of the gear depends on the perfect precision of these segments.

Our manufacturing process ensures that each segment is machined with exacting accuracy, guaranteeing seamless assembly and optimal meshing with the drive pinion. This precision minimizes installation time and eliminates alignment issues, ensuring smooth, reliable operation of your equipment.

Common Applications:

  • Cement & Lime: Rotary Kilns, Dryers

  • Mining & Minerals: Ball Mills, SAG Mills, Grinding Mills

  • Other Industries: Pulp & Paper, Power Generation

Superior Materials and Advanced Manufacturing

The extreme operating conditions of a girth gear demand superior materials and manufacturing methods.

  • Material Selection: We manufacture girth gears from high-strength materials designed for high wear resistance and load capacity. Common choices include:

    • High-Strength Cast Alloy Steel (e.g., ZG42CrMo): Offers excellent toughness and hardenability for large, heavy-section components.

    • Forged Alloy Steel (e.g., 42CrMo4): Provides a superior grain structure and fatigue strength for the most critical applications.

  • Our Manufacturing Process:

    1. Casting / Forging: We begin with a high-quality casting or forging, which is then subjected to heat treatment (Normalizing/Tempering) to relieve internal stresses and refine the grain structure.

    2. Precision Machining: The segments are machined on large-scale CNC vertical lathes and boring mills to achieve precise circularity and surface finish.

    3. High-Accuracy Gear Cutting: Using specialized large-capacity gear hobbing or milling machines, we cut the gear teeth to the specified module and profile, ensuring consistent pitch across all segments.

    4. Drilling & Finishing: Bolt holes are precision-drilled to ensure perfect alignment during on-site assembly.

    5. Rigorous Quality Assurance: Every segment undergoes comprehensive quality control, including dimensional inspection, hardness testing, and Non-Destructive Testing (NDT) such as Ultrasonic (UT) and Magnetic Particle (MT) inspection to guarantee freedom from internal defects.

OEM Replacement and Engineered Upgrades

Whether you need a direct replacement for an existing OEM girth gear or an engineered upgrade for improved performance, we can manufacture to your exact drawings and specifications. We are your reliable partner for minimizing downtime and keeping your critical rotating machinery running.


Request a Quote for Your Girth Gear

Submit your technical drawings and requirements to our engineering team for a comprehensive quote. Ensure the reliability of your mill or kiln with a precision-manufactured girth gear.


Contact us

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