What Is Particleboard and Why Do Flakes Matter?

Particleboard (also called chipboard or flakeboard) is an engineered wood panel made by bonding wood particles with adhesive under heat and pressure. Flake geometry, uniformity, and surface quality are the single most important variables determining final panel performance — affecting bond strength, surface smoothness, and structural consistency across furniture, flooring, and construction applications.

Two Flake Preparation Routes

Route 1 — Direct Flaking (Regular Timber) Uniform logs feed directly into a flaking machine, producing thin flakes for core or surface layers. Advantages: superior flake quality, smooth surfaces, consistent dimensions. Limitation: raw material must be relatively uniform.

Route 2 — Chip Then Flake (Irregular Material) Irregular timber (fork wood, slabs, offcuts, veneer waste) is first chipped, then processed by a double-drum flaker into narrow elongated flakes. Advantages: high efficiency, broad material compatibility, lower labor intensity. Limitation: flake thickness is less uniform and harder to control.

Three Cutting Principles

• Longitudinal — blade perpendicular to grain, motion parallel to grain. Flakes curl easily; not used for flake production.
• Transverse — blade parallel to grain, motion perpendicular to grain. Best flake quality; the standard method for all flaking machines.
• End-grain — blade and motion both perpendicular to grain. Length controllable but thickness variable; high power demand. Used in chipping machines.

Primary Processing Machines

Disc Chipper

A high-speed rotating disc with multiple flying knives shears incoming logs against a fixed counter-knife, producing wood chips discharged by centrifugal force.

• Disc diameter: 1.3 – 3 m | Knives: 3 – 16 | Speed: 150 – 720 r/min | Grinding angle β: 30° – 45°
• Feed options: flat feed (long timber, 4 m+) or inclined gravity feed (short material, under 2 m, angle 45° – 50°)
• Disc face options: flat disc or helical disc — the helical design contacts wood progressively, eliminating end-face crushing and producing more uniform chips
  

Drum Chipper

A rotating drum with flying knives cuts timber against a fixed counter-knife. Chip length is determined by knife projection height; chips exit through a screen below the drum.

• Drum diameter: ~1 m | Speed: ~390 r/min | Knives: 2 – 4 | Knife angle: ~35° | Knife gap: 0.8 – 1 mm | Feed angle: 40°

Disc Flaker

Structurally similar to the disc chipper but optimized for transverse cutting — producing thin flakes from block-form material (log cores, slabs, large offcuts). Forced feed prevents skewing. Flake thickness set by knife projection (~12 mm).

• With scoring knives: small pre-scoring knives sever fibers before the main knife cuts, defining flake length precisely
• Without scoring knives: staggered blade sections offset by 0.3 – 0.5 mm to distribute cutting load

Drum Flaker

Performs transverse cutting on round logs via a rotating knife drum. Key constraint: the ratio of minimum to maximum flake thickness must exceed 0.71 — larger drum diameters achieve better ratios. Knives require a helix angle relative to the drum axis for smooth progressive cutting. Long-axis machines use a segmented drum shaft (several short knife sections) to simplify knife manufacturing and regrinding.

Secondary Processing Machines

Double-Drum Flaker

The standard machine for re-processing wood chips into thin flakes. A knife wheel and an impeller rotate in opposite directions (impeller faster) — centrifugal force draws chips against the knife wheel inner surface, and their relative motion cuts fibers longitudinally into flakes.

• Knife wheel diameter: 600 – 1,200 mm | Knives: 26 – 48 | Knife angle: 37° – 38°
• Flake thickness controlled by knife projection h: surface layer = h 0.35 – 0.45 mm; core layer = h 0.55 – 0.65 mm
• Each machine runs 2 – 3 interchangeable knife wheel sets for continuous operation

MKZ Conical Variant (Maier, Germany): A conical knife wheel with an axially adjustable vortex impeller allows radial clearance (0.25 – 0.5 mm) to be tuned without stopping the machine — offering finer thickness control and significantly reduced wood powder generation. Knife angle: 31° – 37°; bottom knife angle: 47° – 50°; continuous run per knife set: 2.5 – 3.0 h.

Hammer Mill

High-speed rotating hammers break chips into fine particles through impact and friction. Particle size is controlled by screen aperture — common sizes: 8×40 mm, 9×60 mm, 4×35 mm, 8×12 mm.

Refiner (Grinding Machine)

Two precision-grooved discs (one fixed, one rotating) process material through simultaneous compression, shear, and friction — separating wood into individual fibers or ultra-fine flakes. The disc gap is the key process parameter. Essential for high-grade surface layer flakes and MDF fiber production.

Equipment at a Glance

Key Takeaways

Selecting the right combination of processing machines is fundamental to achieving target flake geometry and production economics. The two critical decision axes are raw material form (regular vs. irregular timber) and target flake application (core layer vs. surface layer).

For lines processing regular round timber directly to high-quality flakes, the disc flaker or drum flaker is the primary machine of choice. For lines utilizing diverse or irregular raw materials (including industrial residues), a chipper-to-double-drum-flaker sequence offers maximum material flexibility. The MKZ conical double-drum flaker represents the current state of the art in secondary flaking — offering the most precise thickness control and lowest fines generation of any re-processing machine type.