Heavy-duty Herringbone Girth Gears are indispensable components for large-scale equipment like mining ball mills and heavy gearboxes, thanks to their superior load-bearing capacity and transmission stability. As a Large-scale Steel Casting Specialist with 20 years of expertise, Tenfaye focuses on customized production through rigorous casting protocols to ensure exceptional reliability and stable performance for every gear.
 
1. Digital Simulation & Risk Pre-control (CAE Analysis)
Numerical Simulation: We utilize CAE simulation software and Finite Element Analysis (FEA) to model filling and solidification, pre-identifying potential shrinkage risks in "V-shaped" thermal stress zones.
 
Precision Feeding Design: Based on thermal field analysis, we deploy multi-stage insulating risers and chilling arrays to guide directional solidification, ensuring a dense internal structure free of defects.
 
2. High-Purity Melting & Advanced Molding
Refined Molten Steel: Utilizing the EAF (Electric Arc Furnace) + LF (Ladle Refining Furnace) duplex process, we achieve deep deoxidation and desulfurization, strictly controlling gas content to ensure high material toughness.
 
Composite Sand Molding: For the core gear teeth area, we use sodium silicate sand combined with chromite sand. Its superior thermal conductivity enhances surface hardness and finish (Ra ≤ 12.5μm) while preventing sand inclusion.
 
3. Scientific Pouring & Controlled Cooling
Step-Gating System: A multi-gate stepped pouring system is used to stabilize the molten steel flow rate and prevent sand erosion.
 
Controlled Cooling Program: We strictly execute a long-term slow-cooling curve, allowing the casting to cool uniformly within the mold to suppress thermal cracks at the source.
 
4. Stress Relief Heat Treatment
Normalizing + Tempering Cycles: Utilizing fully computerized temperature control, we execute customized heat treatment protocols to eliminate over 90% of internal casting stresses.
 
5. Precision Mechanical Processing
Heavy-Duty Rough Machining: Removing the casting skin to reveal the gear profile, followed by the initial Non-Destructive Testing (NDT).
 
Secondary Aging Treatment: We implement aging treatment after rough machining to release cutting stresses, ensuring a residual stress elimination rate of over 95% to prevent future deformation.
 
High-Precision Gear Hobbing: Using heavy-duty CNC gear hobbing machines, we strictly control symmetry, pitch accuracy, and contact patterns to ensure smooth transmission. 6. Stringent Quality Assurance (QA/QC)
100% NDT Inspection: Every unit undergoes mandatory Ultrasonic Testing (UT) and Magnetic Particle Testing (MT) before shipment to ensure zero internal porosity and no surface micro-cracks.
 
Full Performance Certification: We provide comprehensive reports covering chemical composition, metallographic structure, and mechanical properties (tensile, impact, and hardness).
 
Searching for a reliable casting partner for your large-scale ball mills or gearboxes?
 
Tenfaye has successfully delivered numerous heavy-duty herringbone gears to Europe, the Americas, and South Africa. We offer extensive experience and a mature international service system.
 
If you require customized large-scale gear solutions, contact our technical team today. Provide your technical drawings or specifications, and we will be happy to offer full technical support and a detailed quotation within 48 hours.