Cast iron rolls are subject to high rolling loads during work, and twists, changes, and conflicts often occur between cast iron rolls. After a certain period of time, the surface needs to be polished to remove defects such as pits, roll marks, and cracks on the surface, and the fatigue layer is gradually removed while repairing the roll shape. The material of the roller is a polymer composed of an iron-based solid solution and alloy carbide. At present, Cr5 rollers are widely used, and the single grinding amount is 0.2-0.3mm. If the small and medium-sized centrifugal rollers cannot mesh at one time, the grinding amount after processing will exceed 0.1mm.
In addition to the mechanical equipment of the grinding machine, the key media and consumables for grinding cast iron rolls are metal cutting fluid and grinding wheels. With the improvement of appearance quality, higher requirements are put forward for metal cutting fluid and grinding wheels.
Cast iron rolls provide excellent chip settling, excellent cooling and cleanliness, and reduced scoring on the roll surface. Select the appropriate grinding wheel type and grinding process parameters to ensure roll shape, external vibration, transverse thread, and external scratches. Does not happen during grinding. Generally speaking, corundum grinding wheels are used for small and medium centrifugal rollers. Matching the corundum grinding wheel according to the material of the small and medium-sized centrifugal roller can achieve higher appearance quality and grinding accuracy. Generally, the problem of roll shape is mainly caused by the grinding wheel being too soft.
Cast iron rolls may have the disadvantage of roll surface vibration, such as too hard grinding wheel or too high feed speed and traverse speed, which needs to be solved by reducing the grinding wheel line speed, reducing feed speed, reducing traverse speed, and increasing roll speed. Cross threading, also known as feed form, occurs when the grinding wheel is improperly calibrated or the feed rate and traverse rate are too high. When the grinding wheel is too soft, the coolant filter fails, and there are abrasive particles floating in the coolant, there will be grinding spots on the appearance of the small and medium-sized centrifugal rollers. Check cast iron roll coolant filter, increase wheel speed, reduce roll speed, and reduce feed rate. The grinding wheel is too hard, the self-sharpening is poor, the passivated sand grains are not easy to fall off, and the surface of the grinding roller is easy to scratch. It is necessary to increase the speed of the grinding roller and reduce the linear speed of the grinding wheel.
