PEGASUS Discs for Low-Consistency Refining

PEGASUS discs are engineered for low-consistency (LC) refining with broader 3–5 mm refining areas that stabilize hydraulic flow and deliver controlled mechanical treatment of fibers.

Controlled fiber development: optimize tensile, SCT, and bonding with predictable curves.
Hydraulic stability: wider refining bands reduce pulsation and plate vibration.
Energy optimization: achieve target strength at lower kWh/t and smoother torque profiles.
Robust metallurgy: wear-resistant alloys and heat treatment for long run life.

Typical Applications

Designed for LC refiners in stock preparation lines across pulp & paper mills.

Pulp types

Bleached hardwood kraft (BHKP), bleached softwood kraft (BSKP)
Recycled OCC, tissue grades furnish, mixed office waste
Non-wood pulps (bagasse, bamboo) with LC refining stages

Paper and tissue grades

Printing & writing, packaging (liner, medium), board
Tissue and towel base sheets
Specialty papers requiring balanced bonding and bulk

Processing outcomes

Improved strength at controlled fines generation
Lower specific energy for equivalent °SR or freeness targets
Reduced plate chatter and improved process stability

Geometry & Flow Design

PEGASUS uses 3–5 mm effective refining areas with optimized bar-to-groove ratios to extend fiber residence time while controlling specific edge load (SEL). Wider bands promote uniform fiber contact and reduce localized peak intensity.

Bar and groove patterns

Progressive bar lead to guide stock with minimal recirculation
Groove depth and width tuned for LC viscosities to mitigate plugging
Edge radiusing for consistent micro-cutting without excessive fines

Hydraulic behavior

Stable pressure distribution across the plate radius
Lower pulsation amplitude, reducing bearing and seal loads
Smoother torque signal aiding advanced control loops

Performance & Energy

PEGASUS targets a favorable strength–energy trade-off in LC stages.

Expected performance deltas

Tensile index: +5–12% at equal energy, depending on furnish
SCT/CD: +3–8% with controlled fines development
Freeness (°SR): reach setpoints with 5–15% lower kWh/t vs. baseline LC plates

Process signals

Reduced torque ripple and power spikes
More stable plate gap for longer on-target operation
Lower vibration at comparable throughput

Note: Actual results vary by refiner, plate wear state, consistency, and furnish chemistry.

Compatibility & Models

Available as full discs or segments for standard low-consistency refiner frames. Common sizes supported; customizations on request.

Typical refiner families

Voith LC series
Andritz/Escher Wyss LC refiners
Valmet/Jylhävaara LC models
Sprout/Bauer type LC refiners

Configurations

Diameters: 20–54 in (approximate range); other sizes by design
Mounting: keyed hub, bolt patterns per OEM
Segment sets or monobloc discs depending on frame

Interchangeability
Designed to match OEM clearances and balance requirements. Engineering verification provided for each frame before delivery.

Technical Specifications

Refining area width: 3–5 mm effective bands
Bar thickness range: 2.5–4.5 mm; edge radius engineered per furnish
Groove depth: 3–6 mm; groove width matched to LC flow regime
Metallurgy: high-chromium white iron or alloyed steel for abrasion resistance
Heat treatment: hardness optimized for wear vs. toughness balance
Hardfacing options: localized overlays on leading edges (on request)
Balancing: ISO-compliant dynamic balance for reduced vibration
Surface finish: shot-peened or ground per application

Reference values shown; final specs confirmed during engineering review.

Operation & Control

Recommended operating window

Consistency: 2.5–4.5% (typical LC range; tune per furnish)
Specific edge load (SEL): target low-to-moderate SEL with broader areas
Throughput: maintain dwell time to avoid over-intensity

Control strategy

Use plate gap control with stable torque setpoints
Monitor power, vibration, temperature, and dilution ratio
Apply ramp-and-hold when transitioning grade recipes

Maintenance

Rotate/flip segments per wear pattern to extend campaign
Inspect edge rounding and groove cleanliness to prevent plugging
Re-validate balance after any segment replacement

Case Snapshot

Packaging mill LC stage, 100% OCC furnish.

Baseline

Power: 240 kWh/t to reach °SR target
Tensile index: baseline 100%
Notable torque ripple and plate vibration

With PEGASUS

Energy: −12% (≈210 kWh/t) at same °SR
Tensile index: +7% vs. baseline
Torque ripple reduced; gap control stayed within tighter limits

Single-line result; verification recommended on-site for each mill.

Catalog & Resources

Ready to specify PEGASUS for your LC stage?