During the conversion of cement plant's 3×80m wet process kiln to 3×50m dry process kiln, severe wear was discovered on the transmission pinion gear after cleaning the drive girth gear. Given the extended production cycle for the new large gear rings, we developed an on-site repair solution using professional welding restoration techniques to extend the service life and ensure continuous cement plant operations.

Repair Technology Solution
1. Process Planning Based on site construction constraints and 45# steel material characteristics, the following welding process was established:

• Root welding: Stainless steel electrodes (A302, φ3.2mm) to form transition layer and improve weld toughness
• Fill welding: Basic low-hydrogen electrodes (J507) for multi-layer filling to ensure weld quality

2. Pre-welding Preparation

• Safe dismantling and horizontal positioning of the gear ring with stable support
• Construction of windproof and thermal insulation facilities for winter operations
• Precise machining and cleaning of welding grooves

3. Preheating and Welding Process

• Preheating Treatment: Ceramic electric heating blankets for uniform surface heating
• Preheating temperature controlled at 180-200℃ to reduce thermal stress
• Welding Process: Edge welding method for groove filling with concave weld profile design Short arc narrow bead non-oscillating welding technique for effective penetration control Reduced weld carbon content to minimize hot cracking tendency Inter-pass cleaning and light peening after each layer to release residual stress 3-5mm grinding allowance for weld height

4. Post-weld Finishing
Professional grinding equipment for precise weld finishing ensuring:

• ​​​​​​​Smooth transition between weld and base material
• Elimination of surface defects and stress concentration points
• Achievement of original tooth surface accuracy requirements

5. Heat Treatment Process

• ​​​​​​​Welding Stress Relief:Ceramic electric heating blankets for localized heat treatment
• Heating temperature 550-650℃, holding for 8 hours
• Double-layer rock wool insulation for slow uniform cooling

As the industry-leading large gear rings manufacturer, Tenfaye offers:

• Custom production capability for girth gear up to 17 meters in diameter
• Comprehensive on-site repair technical service system
• Professional engineering team with proven solutions

Tenfaye provide not only high-quality steel casting parts for cement plant but also complete technical support and maintenance services for our customers.