When we buy, we teach you a method, we can use a pen to strike the side of the long life grinding wheel. That is the side. Then use your ears to listen to the sound. If the sound is crisp, it is the same diamond wheel, which is a qualified product. In terms of positioning, we have to choose a suitable local dish to carry out the next step. First of all, the choice of one is that you can't face the direction of someone nearby or the place where the traffic volume is relatively large. If you can't avoid it, you should build a baffle with a height of more than one meter five. Some people find that the long life grinding wheel is unstable during installation, for two reasons. One is that the grinding wheel has problems when it is manufactured, and the second one is that the installation method is incorrect. When we find that the long life grinding wheel is unbalanced at work, we need to adjust it in time. If it doesn't work, it will be replaced. When we are replacing the diamond grinding wheel and the protective cover, we should check whether it is installed firmly to prevent danger.