The fiber preparation stage is the foundational process where the fundamental quality of the MDF panel is determined. This stage dictates the board's strength, stability, and surface finish. It begins with the precise metering and feeding of wood chips. These chips are then steamed in a digester to soften the lignin, making the fibers pliable for the subsequent refining process. The refined fibers are the heart of the product; the refining process must be meticulously controlled to achieve the optimal fiber length and degree of fibrillation.
Long, well-fibrillated fibers create a stronger interlocking network within the board, directly contributing to its internal bond (IB) strength and modulus of rupture (MOR). After refining, the fibers are dried to a very specific moisture content in a flash dryer. This is a critical step, as inconsistent moisture leads to blisters, poor resin curing, and density variations in the final panel. The dried fibers are then blended with resin, wax, and other additives in a highly accurate dosing system. Uniform coating of each fiber with resin is essential for achieving a homogeneous board with consistent properties. Any compromise in fiber preparation will manifest as defects in the pressed panel, making this stage the most critical for quality control.
