the machining industry is the same important in the world. The machinery manufacturing industry involves a wide range. The most important concept of the manufacturing industry is the precision. There are two concepts in it, one is the processing precision and the other is the measurement precision. How to reflect the size required by the designer is the machining accuracy, and how to know the size of the finished product is the accuracy of measurement. These two precision depend directly on the accuracy of the machine or the measuring machine.

    the machining precision of the mechanical equipment will only lose and not increase, and the machine of 1/100 millimeter precision can only work out the workpiece with error of more than 1/100 millimeter. So, even under the premise of not considering the assembly error, the machinery which is assembled by the machined parts with medium precision can only reach the lower. The precision is to be manufactured into parts of medium precision machinery, which can only be produced by using high precision machining machinery. According to this principle, high precision machining machinery can only be used to produce high precision machining machinery.

    the company that uses this process to process machinery is now mainly in Germany, Switzerland and Japan, which is the reason why these countries can produce high precision machinery. Japan’s precision processing company mainly concentrated in the northern latitude 43 degrees line of Niigata Prefecture. There are meteorology reasons, the Japanese precision craft is learned from the Germans, when the government selected the address of the precision processing industry, the climate and the similar north latitude 43 degrees in Germany were selected. The humidity was smaller and the temperature was around 20 degrees Celsius, which was most suitable for precision processing. At that time there was no air conditioning equipment, it was unimaginable to install air conditioning equipment in the production workshop, so the problem of temperature difference must be noticed in the site selection. The expansion and contraction of material caused by temperature difference had a great influence on the manufacture and assembly of precision products. The temperature difference not only affects the processing work, but the bed of the super precision grinding machine does not use the general cast iron, but the granite is used to reduce the effect of the temperature difference.