Flexo Folder Gluer (FFG): Complete Technical and Buying Guide

The flexo folder gluer (FFG) is the most widely used converting machine in the corrugated packaging industry. It prints, slots, folds, and glues corrugated board sheets into finished shipping boxes in a single pass.

What is a Flexo Folder Gluer?

An FFG machine takes flat corrugated board sheets and converts them into finished boxes — typically Regular Slotted Containers (RSC). It combines four operations that were historically done on separate machines

1. Flexographic printing (1-4 colors)

2. Slotting and scoring

3. Folding

4. Gluing (side seam and/or bottom)

FFG Machine Sections

Feeder Section

Loads and feeds individual board sheets into the machine

Vacuum or friction feeders for consistent sheet delivery

Pile capacity: 500-2000 sheets depending on model

Feeding accuracy critical for print registration

Printer Section

Flexographic printing using rubber or photopolymer plates

1-4 color capability (most common: 1-2 colors)

Water-based or alcohol-based inks

Print area: Up to full sheet size

Registration accuracy: ±1mm typical

Slotter Section

Cuts slots for box flaps

Creates crease/score lines for folding

Adjustable for different box sizes

Rotary slotting for high-speed models

Folder Section

Folds board along score lines to form box shape

Multiple folding configurations available

Handles various board calipers (3-ply through 7-ply)

Gluer Section

Applies adhesive to side seam and/or bottom

Hot melt glue (most common) or cold glue

Compression section ensures bond before exit

Output: Finished, glued boxes ready for palletizing

Key Specifications

Speed: 100-350 boxes/min depending on model and box size

Max Sheet Size: 1200×2400mm typical (varies by model)

Min Sheet Size: 300×400mm typical

Board Caliper: 2-8mm (single wall through triple wall)

Colors: 1-4 flexographic colors

Power Requirement: 30-80 kW

FFG Price Guide (2026)

Basic 1-color: $80,000 - $150,000

Standard 2-color: $150,000 - $300,000

Mid-range 4-color: $300,000 - $500,000

High-speed inline: $500,000 - $800,000

Selection Criteria

1. Box Size Range: Ensure machine handles your product dimensions

2. Production Volume: Match speed to corrugating line output

3. Print Requirements: Number of colors, print quality expectations

4. Board Types: Verify compatibility with your board calipers

5. Changeover Speed: Important for multi-SKU operations

6. Integration: Can it connect inline with corrugating line?

Inline vs. Offline Configuration

Inline FFG

Connected directly to corrugating line stacker

Sheets flow from corrugator to FFG without manual handling

Highest efficiency, lowest labor cost

Requires matched speeds between corrugator and FFG

Best for high-volume, limited SKU operations

Offline FFG

Operates independently from corrugating line

Sheets warehoused between corrugating and converting

More flexibility for multiple box sizes and print jobs

Standard configuration for most small-to-medium factories

Maintenance Essentials

Daily: Clean feed table, check glue nozzles, inspect print rollers

Weekly: Lubricate chains and bearings, check slotting blades, clean ink system

Monthly: Calibrate registration, inspect folding belts, replace worn grippers

Common Issues

Poor print registration: Feeder timing, plate mounting, board warp

Weak glue bond: Glue temperature, application amount, compression time

Inaccurate slotting: Worn blades, incorrect settings, board thickness variation

Feeding jams: Board warp, static electricity, worn feed belts

Matching FFG to Corrugating Line Output

A 200 m/min corrugating line producing 3-ply board generates roughly 150-250 boxes/min worth of sheet material. Your FFG must match or exceed this rate to avoid bottlenecks.

Contact Xuegong for corrugating line and converting equipment consultation.