Plate Configuration
Design of the raised bars and recessed grooves on the face of a refining plate represents the primary tool for tailoring the mechanical action of a refiner to a specific fibre type. This pattern, or refiner segment geometry, dictates how pulp fibres are captured, compressed, and sheared as they pass through the refiner. It determines the balance between fibre cutting and fibre fibrillation during the stock preparation process.
The selected design affects both pulp properties and paper strength.
Flow Profile
The angles of the channels between the bars govern the flow velocity of the pulp slurry within the refining zone. Modifying the refiner segment geometry alters the hydraulic resistance, which affects the motor load of the process. A well-designed plate reduces energy consumption while maintaining the target freeness.
Quality Output
Using the wrong bar pattern for long-fibre softwoods can result in excessive shortening and weak paper sheets. When the refiner segment geometry is matched to the pulp furnish, the resulting paper exhibits high tensile strength and tear resistance. Standard operating practices require periodic inspection of the plates to monitor the rounding of bar edges, which reduces refining efficiency.
Operators replace the plates when the profiles wear down to maintain consistent pulp quality. Selecting the appropriate design is essential for mills producing high-quality print and packaging grades.
