Judges should know of second-hand ball mill grinding rate is with speed, so the second-hand ball mill speed need professional skills, certain experience to regulate, to maximize the benefit of the play. Only do to effectively control the color, we can only reach the expected of second-hand ball mill grinding results. 
At the time of second-hand ball mill equipment work, to do the most is for speed control theory, on the basis of the theory of follow, constantly sum up experience in practice, to find the perfect control of the point of second-hand ball mill. 
Second-hand ball mill speed directly affects the size of the cylinder body movement of grinding medium and the operation effect. When the ball up to a certain height from the barrel in the fall after the state, by the huge impact, the ore is crushed by impact, this time is a balance, not high not low, let the grinding results more prominent. 
In the actual operation of second-hand ball mill, the control speed, we need to practice a lot and summarizing, everywhere to look, can form the best feeling.