Overview
The Rectifier Roll (also known as an Evener Roll) is a critical internal component of the headbox, specifically designed to stabilize the pulp flow. Located just before the slice, it eliminates large-scale turbulence and breaks up fiber bundles (flocs) to ensure a perfectly homogenized suspension. VANVEO’s rectifier rolls are engineered for high-speed stability and long-term durability.
Working Principle
As the stock flow passes through the rotating rectifier roll, the specifically engineered hole patterns create a controlled micro-turbulence. This process serves two purposes: it prevents fiber sedimentation and mechanically breaks down fiber flocs. The rotation speed is synchronized with the flow velocity to maintain a uniform jet-to-wire delivery.
Key Features
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CNC Precision Drilling: Every hole is CNC drilled and countersink-finished to ensure zero burrs.
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Superior Surface Finish: Multi-stage Mirror Polishing (Ra < 0.4μm) prevents fiber “hanging” and slime buildup.
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Optimized Open Area Ratio: Tailored (typically 35%-50%) to match your specific paper grade and machine speed.
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Anti-Corrosion Material: Constructed from high-grade SS304 or SS316L for maximum lifespan.
Applications in Headboxes
VANVEO’s stainless steel rectifier rolls are essential for:
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Air Cushion Headboxes: Maintaining flow uniformity and air pad stability.
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Open Headboxes: Improving formation and stabilizing gravity-fed stock.
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Component Replacement: Ideal for upgrading existing headboxes to restore paper formation quality.
Technical Specifications
| Parameter | Specification |
| Material | SS304 / SS316L / Custom Alloy |
| Diameter | 200 mm – 600 mm (Customizable) |
| Wall Thickness | 8 mm – 15 mm |
| Open Area Ratio | 35% – 52% |
| Surface Treatment | Internal & External Mirror Polishing |
Why Choose VANVEO?
Unlike standard rolls that may have rough hole edges, our Rectifier Rolls undergo a specialized deburring process. Rough edges cause “stringing”—where fibers catch and form slugs—leading to paper breaks. VANVEO’s mirror-smooth finish ensures a clean, uninterrupted flow, significantly reducing downtime and improving the Basis Weight (BW) profile.
Maintenance & Care Tips
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Cleaning: Use high-pressure water to clear any potential blockages in the holes.
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Inspection: Regularly check for surface scratches that could trap fibers.
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Lubrication: Ensure the rotation drive and bearings are properly lubricated to prevent vibration.
FAQ
Q: What is the lead time for custom rolls?
A: Typically 4-6 weeks including dynamic balancing tests.
Q: Can I upgrade my old headbox?
A: Yes, we can manufacture replacement rolls based on your technical drawings.
Q: Does it come with a balance report?
A: Yes, every roll is shipped with a comprehensive quality and balance certification.
