Refiner Plate Wear Causes and Impact on Pulping

Refiner plate, as crucial and easily worn components in pulping and wood-based panel manufacturing, are the core parts that directly exert force on the fibers. The rationality of the refiner plate’s structural parameters significantly impacts the quality and yield of fiber production, as well as energy conservation, consumption reduction, and production costs.

Refiner plate wear exhibits both commonalities with general metal wear and its own unique characteristics. It is related not only to the properties of the fiber raw materials but also to the characteristics and quantity of inclusions within the fibers. Refiner plates generally need to be replaced when they wear down to a certain extent. In pulp mills, paper mills, and In the pulping process of the hot mill section of artificial board, premature replacement of refiner plates is often necessary due to abnormal wear. Normal wear refers to the refiner plate being used normally and reaching a certain service life. Non-functional wear such as tooth breakage and edge curling is called abnormal wear. Abnormal wear of refiner plates affects production, increases the cost of spare parts and the workload of replacement, and often disrupts the pulping process.

The Influence of Refiner Plate Material on Wear

Common refiner plate materials include multi-alloy steel, stainless steel, and cast iron. These materials have good hardness but poor impact resistance. If the tooth width is small, accidental tooth breakage and saw tooth wear often occur. Uneven wear causes the refiner plate to be taken out of service before reaching its intended lifespan, affecting the continuity of pulping production and pulping indicators. It can also cause fluctuations in pulping current and high power consumption.

Serrated Refiner Plate Wear

White cast iron grinding discs often suffer from uneven wear due to material inhomogeneity caused by factors such as casting temperature control. This is particularly problematic in low-concentration, high-intensity pulping, leading to wavy or serrated wear between the moving and stationary discs. The wear patterns of the moving and stationary discs are engagement, causing fluctuations and increases in pulping power, severely impacting pulping efficiency and energy consumption.

Edge Curling and Passivation of Refiner Plate

Alloy and stainless steel refiner plates with lower hardness have better impact resistance, but due to their softer materials, they tend to wear out faster. During use, uneven wear, wavy patterns, passivation, “clogged grooves,” and “edge curling” can occur, reducing beating efficiency. This is especially true when increased cutting action or beating degree is required during beating, leading to increased refiner power and accelerated wear. Edge curling of some teeth can cause groove closure, while “clogged grooves” affect the exchange and movement of paper pulp within the tooth grooves, causing paper pulp blockage in the refiner plate grooves.

Refiner Plate Fatigue Wear

Fatigue wear is a type of high-wear or excessive wear. Fiber raw materials often introduce numerous impurities into the grinding zone, mostly granular gravel and other debris (Al₂O₃, SiO₂, SiC, and fragments worn off from the refiner plate). These impurities, along with the slurry, form a high-speed abrasive flow that impacts the refiner plate surface with kinetic energy or rolls on it. This repeated impact and rolling generates high contact stress on the metal surface, causing repeated plastic deformation of the refiner plate material. In the deformed localized areas, metal fatigue leads to cracks that propagate and intersect under alternating stress, causing surface cracking and debris shedding. Fatigue wear is also the result of repeated abrasive action on the refiner plate, characterized by numerous extremely fine spots appearing on the refiner plate surface.

By summarizing several typical wear patterns and effects of refiner plates, different wear modes are demonstrated. Sun Hong provides various types of refiner plates with high wear resistance, effective impact resistance, and improved fiber morphology and physical properties after pulping.