The Importance of the Angle of the Conical Refiner Plate

The refining process plays a crucial role in the entire papermaking process. At present, the most commonly used refining machines in China include double disc refiner, conical refiner, and cylindrical refiner. For the conical refiner, the size of the cone angle of the conical refiner plate and the concentration of the pulp directly affect the refining effect and power consumption. The effective grinding power and effective surface load are the main parameters for measuring the refining effect and energy consumption.

Basic Structure of Conical Refiner

The pulp of the conical refiner is pumped into the grinding chamber through the feed pipe at the small end of the conical head, and discharged from the discharge pipe through the gap between the conical refiner plate. Impurities in the pulp settle into the debris collection chamber under gravity before passing through the gap between the conical refiner plate. Beating is carried out between the dynamic refiner plate and the static refiner plate, and its structural characteristics are:

• Adopting the form of axial pulp inlet and radial upper pulp outlet, with a long precision refining zone;
• There is an independent wear indicator that can detect the edge wear of the refiner disc;
• The feed pressure device can make the entire shaft move horizontally together with the conical refiner rotor;
• There is a debris collection chamber at the feed end that is easy to empty.

Working Principle of Conical Refiner Plate

The grinding zone is composed of a truncated conical rotor (with a rack) and a stator of the same shape, and the clearance between the refiner plates is controlled by an axial displacement adjustment mechanism. The fiber material enters the grinding zone through the feeding channel and completes fiber separation and pulverization under the action of rotational shear. The processed pulp is output through the discharge channel.

The Influence of Refiner Plate Conical Angle Variation on Refining Effect

• the cone angle of the conical refiner plate is an important parameter that affects the grinding effect in a conical refiner. Increasing the cone angle appropriately can improve the effective grinding work and reduce energy loss;
• When the cone angle is too large, it will reduce the effective surface load and decrease the accuracy of the tool bar clearance;
• From the calculation and analysis of the example, it can be concluded that the appropriate range of cone angles must be comprehensively influenced by three factors: effective surface load, axial thrust, and tool clearance accuracy;
• Under the same pulp processing capacity, larger cone angle refiner have smaller external dimensions, shorter unit lengths, simpler structures, and are easy to replace and maintain conical refiner plate.