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.