How Our Slewing Drives Achieve Long-Term Corrosion Protection?

How Do Our Slewing Drives Achieve Such Exceptional Rust Resistance?

The following is the rigorous surface treatment process applied to every slewing drive, ensuring its durability and longevity under demanding outdoor operating conditions:

1. Shot Blasting—Laying the Foundation for Rust Prevention

All raw slewing drive castings undergo a 20-minute shot blasting treatment using 0.4mm steel shot. This process thoroughly removes surface scale and residues, creating a uniform surface roughness that significantly enhances the adhesion of subsequent protective coatings.

2. High-Standard Cleaning—Meeting International Norms

Following shot blasting, the surfaces are subjected to high-pressure air cleaning. This ensures a surface cleanliness level of Sa 2.5 (per ISO 8501-1), guaranteeing the complete absence of oil stains and rust, thereby providing a pristine substrate for the application of protective coatings.3. Electrophoretic Coating — Building a Protective Foundation

Every slewing drive undergoes rigorous electrophoretic treatment:

• Alkaline chemical degreasing at 60°C → Hot water rinse at 60°C for 2 minutes → Flowing cold water rinse for 1 minute
• Phosphating treatment at 60°C for 10 minutes → Passivation treatment for 2 minutes
• Electrophoretic deposition in a DC electric field, forming a uniform and dense base coating
• Flowing clean water rinse → Oven curing at 165°C for 60 minutes

4. Double Powder Coating — Reinforcing Surface Protection

Utilizing Epoxy AL180CS material, the slewing drives undergo a double powder coating process:

• First powder coating (60–80 μm) → Curing at 160°C for 10 minutes → Natural cooling
• Second powder coating (60–80 μm) → Secondary curing at 160°C for 10 minutes

5. Rigorous Validation — 720-Hour Salt Spray Test 

Finished slewing drives that have completed the full process described above are submitted for a neutral salt spray test. After 720 hours, the base material exhibits no red rust, and the coating shows no blistering or peeling; this meets the C4 anti-corrosion standard, enabling the drives to confidently withstand outdoor environments characterized by high humidity and moderate levels of pollution.

In which scenarios are our slewing drives suitable?

• Construction Machinery: Cranes, excavators, aerial work platforms
• PV Tracking Systems: All-weather outdoor operation with extremely high anti-corrosion requirements
• Lifting and Transport Equipment: Ports, mines, and other humid or corrosive environments
• Any outdoor application requiring reliable rotary transmission

Why choose our slewing drives?

1.C4-rated; validated by a 720-hour salt spray test

2.Electrophoretic primer combined with a secondary epoxy powder coating for dual-layer protection

3.Precise parameters defined for every process step, ensuring full control and traceability throughout the entire workflow

4.Reduces maintenance frequency and minimizes losses due to downtime

5.Designed for outdoor operating environments characterized by high humidity, atmospheric pollution, and significant temperature fluctuations 

Customer Benefit: You Buy a Slewing Drive, but You Gain Long-Term Peace of Mind

A slewing drive with inadequate rust protection may suffer from corrosion, seizing, diminished precision, or even complete failure within just three to five years—resulting in costly repairs and replacements. In contrast, every slewing drive we deliver undergoes over ten distinct surface treatment processes—from raw casting to finished product. We let the data speak for itself, backed by results from a rigorous 720-hour salt spray test. This ensures that throughout the entire lifecycle of your equipment, you can truly experience "less worry, more productivity."