Types and Applications of Refiner Plate in Refiner Machines

Refiner plates are an important component of double disc. By altering the morphology of the fibers in the pulp, they indirectly affect paper properties such as strength, uniformity, and transparency. Refiner plates come in many types and tooth profiles and are widely used in various fields.

Classification of Refiner Plate

• Conical refiner plate: conical refiner plate is one of the most common refiner plate in paper pulp mills. Its design is conical and suitable for processing various fiber materials such as wood, waste paper, etc.
• Sawtooth refiner plate: The edge of the saw tooth refiner plate has serrations, suitable for grinding materials with high fiber content. It can effectively crush fibers and improve the quality of pulp.
• Smooth surface refiner plate: Smooth surface refiner plate is mainly used for fine grinding slurry, such as food processing, chemical raw materials and other fields.
• Alloy refiner plate: The alloy refiner plate is made of high-strength alloy material with good wear resistance, suitable for grinding pulp of high hardness materials.
• Superhard refiner plate: Superhard refiner plate has extremely high wear resistance and is suitable for high wear and high demand grinding environments, such as waste paper pulp with high fiber content.

Refiner Plate Design and Selection

Tooth Width

The tooth width of low concentration refiner plate does not have a certain regularity. Under the condition of a certain tooth width and groove width, when dealing with free pulp, it is necessary to consider appropriately reducing the tooth width and correspondingly increasing the groove width to weaken the squeezing friction of the tooth surface and enhance the cutting ability. When dealing with viscous pulp, it is considered to increase the tooth width and reduce the groove width to enhance the tooth surface effect, suppress the cutting effect, and thus enhance the ability to separate fibers.

Slot Width

Considering the smooth passage of pulp fibers in the tank and the sufficient space to form necessary vortices in the refiner’s fixed disc groove, the fibers are frequently exchanged between the groove and the tooth surface, and continuously subjected to beating treatment. The selection of the groove width is preferably equal to or slightly greater than 2-3 times the average length of the treated pulp fibers.

Tooth Height

During the pulping process, the teeth of the refiner plate are subjected to bending loads during operation. Due to considerations of strength and service life, the tooth height of the refiner plate is generally limited to 1-2 times the tooth width. If it is too high, the pulp is not easily exchanged between the grooves and tooth surfaces of the refiner plate, and the fibers cannot receive the beating effect. At the same time, it may also cause tooth punching due to excessive teeth and insufficient strength. But if the tooth height is too low, the service life of the refiner plate will be shorter and it will affect the throughput of the refiner plate. Generally, the tooth height of the refiner plate is selected as 5.5-7.5mm. When dealing with viscous pulp, choose a lower tooth height, and when dealing with free pulp, choose a higher tooth height.

Tooth Profile Angle

The tooth profile angle refers to the angle between the teeth of the refiner plate and the radius, which has a significant impact on the pumping effect of the refiner. When the tooth profile angle increases, on the one hand, the number of teeth on a certain specification of refiner plate needs to increase, the beating effect is enhanced, and there is a tendency to suppress cutting. On the other hand, as the pumping effect increases, the effective power used for pulping correspondingly decreases. Therefore, the tooth profile angle is generally controlled between 10 ° and 20 °. When dealing with sticky pulp or short fibers that do not require cutting but only require loosening, the angle should be chosen to be larger. When dealing with free pulp, the fibers should be cut, and the tooth angle should be chosen to be smaller.

Pulp Barrier

The function of the baffle ring is to facilitate the exchange of fibers on the groove and tooth surface, and to prevent fibers from directly passing through the refining zone without being treated. However, setting the baffle ring generally reduces the throughput of the mill and thus lowers the product of the mill. At present, the baffle ring is divided into open baffle and dark baffle, and their difference lies in the height of the baffle ring. The different functions and characteristics of these two types of pulp mainly lie in guiding the pulp flow.

In short, there are various types of refiner plate for pulp mills, which have a wide range of applications. Choosing the appropriate refiner plate is of great significance for improving pulp efficiency, reducing energy consumption, and enhancing product quality. In practical applications, the appropriate type of refiner plate should be selected based on factors such as material characteristics and production requirements to ensure the optimal performance of the pulp mill. Meanwhile, attention should also be paid to the maintenance and replacement of refiner plate to ensure smooth production.