Advanced Correcting Rolls (Pot Steering Rolls) for Continuous Hot-Dip Galvanizing Lines (CGL)

Product Overview

In high-speed Continuous Hot-Dip Galvanizing Lines (CGL) and Galvanume Lines (CGL-AlZn), precise strip tracking is critical to preventing edge defects and maintaining coating uniformity. Operating submerged in the severe 450℃ - 480℃ molten zinc bath, our High-Precision Correcting Rolls (also known as Pot Steering or Adjusting Rolls) serve as the primary defensive mechanism against strip mistracking, crossbowing, and sickle camber.

By dynamically interacting with external hydraulic or servo alignment systems, our correcting rolls instantaneously adjust the strip tracking path. This ensures the steel strip passes perfectly centered through the critical air knives, preventing catastrophic line scraping, strip tearing, and edge over-coating.

Technical Edge & Engineering Advantages

1. High-Density Anti-Dross HVOF Coating

To combat aggressive liquid metal corrosion and mechanical wear, the roll surface is armored using state-of-the-art HVOF (High-Velocity Oxygen-Fuel) Thermal Spraying with a specialized WC-Co-Cr (Tungsten Carbide) or Mo-B (Molybdenum Boride) cermet matrix.

• Surface Hardness: ≥HV1000

• Porosity: ＜1%

• Bond Strength: ≥70 MPa

• Benefit: Maximum chemical inertness against molten zinc, drastically suppressing zinc dross pick-up and eliminating surface marking on high-end sheets.

2. Flawless Centrifugal Casting Metallurgy

The roll shells are cast using a high-purity Centrifugal Casting process with low-silicon, ultra-low carbon austenitic stainless steel (e.g., 316L, 317L, 1.4404) or customized cobalt/nickel-based superalloys. This guarantees a dense, homogeneous microstructure free of internal porosity and shrinkage cavities, completely eliminating thermal warping under long-campaign high-temperature cycles.

3. Reinforced Wear-Resistant Journals

Because correcting movements require constant relative sliding under high tension without conventional lubrication, the roll journals are engineered with Stellite alloy cladding or embedded advanced structural ceramic sleeves. This configuration reduces the friction coefficient to a minimum, preventing journal seizure and extending the zinc pot campaign life.

4. Optimized Groove Engineering & Metrology

Available with precision-machined micro-spiral, straight, or chevron grooves designed to rapidly expel trapped liquid zinc and dross particles. Every roll is 100% dynamically balanced to ISO 1940 Grade G2.5 / G1.0 with strict geometric run-out tolerances ($le$ 0.02mm) to ensure resonance-free operation at line speeds up to 200 m/min.

Technical Specifications

Global Engineering Support

We support full OEM/ODM manufacturing based on your precise engineering blueprints or original equipment data sheets. Contact our engineering sales team today for a technical proposal and a competitive commercial quotation.