PULP & PAPER INDUSTRY – CHAIN CONVEYING SYSTEMS & COMPONENTS

Woodyard & Chip Handling

Apron Feeders for Wood Chips / Logs

• Purpose: Controlled feed of logs or wood chips from truck dumpers or silos to screening or chipping units.
• Chain Type: Drop-forged link chain with wide apron pans.
• Design Features:
  • Pan width: 800–2000 mm (Higher customizable sizes available).
  • Chain pitch: 160 mm / 200 mm / 250 mm (Higher customizable sizes available).
  • Pans with anti-jam cutouts and curved edges.
  • Capacity: 200–800 TPH (Higher customizable parameters available).

Chip Reclaimers

• Purpose: Automated chip recovery from radial piles or silos.
• Chain Type: Twin-strand forged chain with scraper flights.
• Specs:
  • Flights made of AR steel or UHMWPE-laminated bars.
  • Slow-speed operation with self-cleaning design.

Drag Chain Conveyors (Green Chips / Oversize Transfer)

• Function: Horizontal or inclined transfer from screening to silo or metering bin.
• Chain Type: Drop-forged steel chain with fixed or articulated flights.
• Extras:
  • Overflow chutes and inspection hatches.
  • Optional bin activators at discharge end.

 Pulping Area (Digester Feed & Washing)

Bucket Elevators (Dry / Moist Chip Elevation)

• Purpose: Elevating washed or dry chips to digester or soaking tanks.
• Chain Type: Central forged chain or round link bucket elevator chain.
• Design Highlights:
  • Height: 15–40 m (Higher customizable sizes available).
  • Buckets with curved profile for chip containment.
  • Self-cleaning bottom pulleys.

Chemical Feeding Conveyors (Lime, Caustic Soda)

• Purpose: Dosing powdered additives to digesters or mixers.
• Chain Type: Forged scraper chain in enclosed trough.
• Features:
  • Designed to eliminate buildup.
  • Anti-static and corrosion-resistant liners available.

Stock Preparation & Trim Handling

Trim Conveyors (Broke & Edge Waste)

• Function: Conveying paper edge trims, reject sheets, broke to repulper.
• Chain Type: Flat-top drag chain or steel hinged chain.
• System Details:
  • Built-in tensioners.
  • Floor-level or mezzanine-mounted systems.
  • Optional diverter gates for dual discharge points.

Drag Chain Conveyors (Rejects & Screen Residue)

• Function: Disposal of heavy rejects like plastic, metal wires, sand.
• Chain Type: Forged steel drag chains with open flight paddles.
• Design:
  • Trough liners for abrasive residue.
  • Screw–chain hybrid versions also available.

Recovery Boiler, ESP, and Ash Handling

Flow Conveyors for ESP Dust

• Purpose: Transfer dry fly ash from recovery boiler baghouse to silo.
• Chain Type: Drop-forged scraper chain with minimal spillage clearance.
• Specs:
  • Chain pitch: 142–200 mm (Higher customizable sizes available).
  • Air-tight casings.
  • Optional nitrogen blanketing for explosive dust control.

Submerged Scraper Conveyor (for Ash Hopper Discharge)

• Chain Type: Forged twin-strand scraper chain.
• Usage: Bottom ash discharge from smelter units or biomass boilers.
• Materials: Heat-resistant alloy steel for wet, hot ash environment.

Final Storage & Dispatch

Silo Discharge Chain Conveyors

• Purpose: Controlled discharge of chips, ash, lime, or pulp powder to truck loaders or screw feeders.
• Chain Type: Central drag chain or dual-strand paddled chain.
• Options:
  • Variable pitch for metered flow.
  • Integration with telescopic spouts.

TYPICAL CHAIN TYPES USED IN PULP & PAPER MILLS

CONSTROMECH ADVANTAGES IN PULP & PAPER INDUSTRY

• Chains forged and machined from Cr-Mn or 35CrMo4 alloy steels, case hardened for longevity.
• Buckets, pans, and scrapers available in MS,  Hard plates up to 550BHN, or UHMWPE-clad versions.
• Chain & sprocket assemblies designed for non-stop, high-moisture, fibrous environments.
• Retrofits and reverse engineering for OEM equipment compatible sizes.
• Silent blocks, adjustable tensioners, take-up guides, and pre-assembled elevator kits available.