How accurate are CNC machine tools in my country? How big is the gap with foreign countries.
To judge the level of a machine tool, it depends on its repeated positioning accuracy whether the repeated positioning accuracy of a machine tool can reach 0.005mm (ISO standard.
Statistical method) is a high-precision machine tool. Below 0.005 mm (ISO standard. Statistical method), it is a very high precision machine tool which must have the best bearings and screws.
When talking about “precision” of CNC machine tools, it is important to clarify the definitions and calculation methods of standards and indicators.
When Japanese machine tool manufacturers specify “accuracy”, they generally use the JISB6201, JISB6336 or JISB6338 standards. JISB6201 is generally used for general machine tools and ordinary CNC machine tools.
JISB6336 is generally used in machining centers, while JISB6338 is generally used in vertical machining centers. The three standards above are basically the same when it comes to defining position accuracy.
This article only uses JIS B6336 as an example, because on the one hand, this standard is relatively new, and on the other hand, it is slightly more precise than the other two standards.
European machine tool manufacturers, particularly German ones, generally adopt the VDI/DGQ3441 standard.
American machine tool manufacturers generally adopt the National Machine Tool Builder’s Assn (NMTBA) standard (this standard comes from a study by the American Machine Tool Builder Association,
Promulgated in 1968 and later revised).
The standards mentioned above are all related to ISO standards.
For example, the dimensional accuracy and shape accuracy of typical parts processed by machining centers are compared with domestic and foreign levels in China, they are about 0.008-0.010mm.
The international advanced level is 0.002~0.003mm.
Although the development of China’s machine tool manufacturing industry has experienced ups and downs, it has always paid more attention to CNC technology and CNC machine tools and has strong market competitiveness.
However, in terms of mid- and high-end CNC machine tools, there is still a large gap between the development of some advanced foreign products and technology, and most of them are in the technology tracking stage.
Ultra-precision machining currently refers to dimensional and positioning accuracy of 0.01 ~ 0.3 μm, shape and contour accuracy of 0.003 ~ 0.1 μm and surface roughness of workpieces in steel Ra≤0.05 μm.
Copper parts Ra≤0.01μm. Domestically developed ultra-precision CNC lathes and CNC milling machines have been put into production. Currently, there is a need to develop ultra-precision grinding machines and ultra-precision composite processing machine tools in terms of varieties.
At the same time, it is necessary to further improve the performance of ultra-precision spindle units, ultra-precision guide rail sub-units, ultra-precision fluid drive systems, ultra-precision contour control technology and nano-resolution CNC systems and accelerate their engineering.
Ultra-precision machine tools are mainly used to solve the ultra-precision processing of national high-tech and key national defense products. Although the demand is not large, it is a sensitive technology blocked by foreign technology.
On the other hand, in-depth research on ultra-precision machining technology and the extension of its results will contribute to the development and industrialization of high-precision machine tools that require high machining precision at submicron level.
Daguang focuses on providing solutions such as precision CNC machining services (3-axis, 4-axis, 5-axis machining), CNC milling, 3D printing and rapid prototyping services.
