Iron casting is the commonly cast iron craft products in iron casting process. As with its quality problem, it is noticeable. The wear part of ball mill generally uses the iron casting. The ball mill is widely used in mineral processing production line, cement production line and aerated concrete production line. The main task of a ball mill grinding raw material is small. However the rotating speed of the ball mill directamente determines the moving state of the grinding media and the effect in the cylinder grinding.
(a) When the ball mill rotates at a high speed, the ball will be “lifted” highly. After the ball is lifted to a certain height, it will separate from the barrel and falls along a parabolic trajectory in throwing working state. The ball will gain a great impact at the drop point. The ore is mainly ground by the impact, and the grinding efficiency is high. (b) When the ball mill rotates at a low speed, the ball of mill ball raised at a low height, the ball will roll down from the top of the ball charge because of its own gravity and presents a cascading state, at which time the impact force of the ball is very small but the grinding effect is evident. However, the ore is mainly ground by grinding and the grinding efficiency is not high.
(c) When the rotating speed of the ball mill exceeds a certain limit (speed is very high), the ball will rotate with the cylinder to rotate without falling in centrifugal running state. The ball will not gain any impact which means not grinding efficiency. And also we have to understand several factors impacting the ductile cast iron as the following: The first is the operation process. Formulate rational process operation procedures to improve the technical level of the workers and correctly take the procedure into practice. Control and check the quality of the casting in the manufacturing production. The second is to possess a reasonable casting process. That is, choose appropriate parting surface and modelling, making the core method, setting up reasonable casting steel, cold iron, take the mouth and pouring system and so on according to the structure of the ductile cast iron, the weight and sizeof wear parts, alloy casting properties and production conditions. To ensure that you get the high quality casting iron. The third is the quality of raw materials in the casting. If the quality of the raw materials such as metal burden, refractory material, fuel, flux, metamorphic agent, casting sand, sand binder, coating of the material and is substandard, the cast iron piece will produce pinhole porosity, slag, adhering sand and other defects. Which will influence the appearance quality and internal quality of ductile cast iron, or even make the ductile cast iron scrap. With the progress of industry and energy conservation and environmental protection, the request of the number of wear parts and the varieties will also expand unceasingly.