GI Strip Slitting Line

Galvanized (GI) strip slitting lines require specialized handling to maintain the protective zinc coating and achieve precise edge quality. Shijiazhuang Faith Machinery Co.,Ltd offers GI strip slitting solutions featuring corrosion‑resistant components, gentle tension control, and integrated lubrication systems. This article examines the unique requirements of GI processing, line features, customization, and service offerings.

1. Safeguarding Coating Integrity

1. Non‑Marking Rollers: Entry and exit guide rolls use polyurethane or reinforced PVC sleeves to prevent coating abrasion.

2. Controlled Tension Zones: Multi‑zone tension control, based on load‑cell feedback, avoids coating cracks or flaking—especially critical for thinner zinc layers.

3. Edge Brushing Units: Optional soft‑bristle brushes remove loose zinc particles from slit edges, reducing debris on recoils.

2. Line Components and Workflow

• Coil Car and Decoiler: Featuring hydraulic expansion mandrels with low‑friction surfaces to protect coating on the coil ID.

• Slitting Section: Rotary slitting knives with fine‑tuned gap adjustment ensure clean cuts without tearing or coating delamination.

• Recoiler and Coil Build: Coils are rewound onto “pancake” spools or mandrels with adjustable traverse guides to maintain neat, concentric winding.

• Lubrication System: Precise oil mist or roller application reduces friction during slitting without contaminating the zinc layer.

3. Precision Control and Automation

• Edge Detection Sensors: Non‑contact optical sensors detect slit edge position, guiding the recoiler traverse to prevent “dog‑eared” coil edges.

• PLC‑Driven Tension Profiling: Recipe‑based tension profiles accommodate both GI and Galvalume® coils, adjusting for varied coating thickness and substrate stiffness.

• HMI Interface: Intuitive graphic screens display line speed, tension zones, coil diameter build, and maintenance alerts.

4. Customization and Capacity

• Material Range: Suitable for GI strip thicknesses from 0.15 mm to 2 mm and widths up to 1,600 mm.

• Slitting Variety: Slit widths from 8 mm to 800 mm; optional micro‑slitting modules enable ultra‑narrow widths down to 4 mm for specialty applications.

• Throughput Targets: Standard lines operate up to 150 m/min, with higher speeds achievable through dual‑slitting frames and high‑response tension controls.

5. Lifecycle Support and Maintenance

• Commissioning and Start‑Up: On‑site support ensures correct tension‑zone setup, decoiler alignment, and coating‑friendly handling practices.

• Operator and Maintenance Training: Focused instruction on coating‑sensitive adjustments, roller sleeve replacement, and lubrication management.

• Preventive Maintenance: Regular inspections of roller sleeves, knife bearings, and tension sensor calibration to prevent coating damage and maintain slit quality.

• Spare Parts and Consumables: Ready supply of slitting knives, PU roller covers, and low‑friction mandrel seals to ensure continuous operation.