Stacker and Board Delivery Systems: Corrugating Line End Section Guide

The stacker is the final machine on a corrugating line. It receives cut sheets from the cut-off, organizes them into neat stacks, and prepares them for downstream converting or shipping. A well-configured stacker maximizes line efficiency and protects board quality.

Stacker Functions

1. Receive individual sheets from cut-off at line speed

2. Count sheets per stack (programmable)

3. Align and square each stack

4. Compress stacks for stability

5. Discharge stacks to conveyor or bundling system

6. Handle multiple widths simultaneously (multi-cut lines)

Types of Stackers

Counter-Stacker (Most Common)

Sheets counted and dropped onto accumulating platform

Platform lowers as stack grows

When count reached, full stack discharged laterally

Speed: Up to 350 sheets/min

Standard on most corrugating lines

Belt-Stacker

Sheets conveyed onto stacking belts

Belts jog sheets into alignment

Gentler handling for lightweight or printed board

Better for high-quality liner surfaces

Bypass Stacker

Can divert sheets to bypass stacking

Used when connecting inline to converting equipment

Sheets flow directly to FFG without stacking

Essential for inline corrugator-to-FFG configurations

Multi-Stacker (Multi-Cut Lines)

Separate stacking stations for each width

Slitter scorer cuts 2-3 widths simultaneously

Each width stacked independently

Improves efficiency for multi-order production

Key Specifications

Stacking Speed: Must match or exceed cut-off speed

Max Sheet Size: Match line working width and cut length

Max Stack Height: 800-1500mm typical

Sheets Per Stack: Programmable, typically 20-50 sheets

Number of Stacks: 1-3 simultaneous (multi-cut)

Stack Accuracy: ±2mm alignment tolerance

Board Quality Protection

The stacker is the last point where board quality can be affected before converting

Gentle sheet handling prevents edge damage

Proper alignment avoids dog-eared corners

Controlled stacking pressure prevents board crush

Adequate support prevents bottom sheet bowing

Anti-static systems prevent sheet misfeeding

Bundle and Delivery Systems

After stacking, boards typically go through

Strapping/Bundling

Plastic strap or band applied around stack

Secures stack for handling and transport

Automatic or semi-automatic systems

Cross-strapping for tall stacks

Conveyor Delivery

Belt conveyors transport stacks to warehouse or converting area

Right-angle transfers for space-efficient layouts

Automatic routing to different destinations by order

Forklift Loading

Stacks placed on pallets for forklift handling

Automatic pallet dispensers and loaders available

Standard pallet size: 1200×1000mm or regional equivalents

Waste Handling Integration

The stacker area also manages edge trim waste

Trim chutes collect edge waste from slitter scorer

Pneumatic or belt conveyors transport trim to baler

Automatic baling systems compress waste for recycling

Proper waste removal prevents accumulation and fire risk

Stacker Maintenance

Daily

Check sheet counting accuracy

Inspect stacking platform condition

Clean dust and debris from stacking area

Verify discharge mechanism operation

Weekly

Lubricate lift mechanism and guides

Check belt conditions on belt-stackers

Inspect squaring paddles and alignment devices

Calibrate sheet counter

Common Problems

Miscounted Stacks

Sensor misalignment or dust on counting sensors

Sheet double-feeding from cut-off

Solution: Clean sensors, check cut-off timing

Poor Stack Alignment

Worn squaring paddles, uneven stacking platform

Solution: Replace wear parts, level platform

Sheet Damage at Stack

Excessive drop height, worn impact surfaces

Solution: Adjust platform lowering speed, replace padding

Stack Discharge Jams

Misaligned discharge conveyor, stack too tall

Solution: Align discharge, reduce sheets per stack

Integration with Downstream Equipment

Offline Converting: Stacks conveyed to warehouse, then manually loaded to FFG

Inline Converting: Bypass stacker feeds sheets directly to printer slotter or FFG

Pre-Print Lines: Stacks may feed to laminating station for printed sheet application

Contact Xuegong for corrugating line configuration including stacker and delivery systems.