Throughout these emerging industries, we find that their typical products have one common feature, that is, large-scale. From the machining point of view, the workpiece is generally heavy and super heavy, and the size of the workpiece exceeds the machining range of the original machine tool. The machining of large workpieces belongs to the extreme manufacturing category, and many new requirements are put forward for the structure of the machine tool, machining technology, and on-site management. Moreover, we should see that these industries have extremely high requirements for reliability. Safety issues are related to the well-being of the people ’s lives and the protection of the environment. There must be no mistakes. In addition, large workpieces themselves are of great value, and the scrap rate during machining must be strictly controlled.
For the machining of large workpieces, the working table of the machine tool is generally more than 2000mm × 2000mm, and the output power is at least 40kW; because the workpiece is large and heavy, most of the machine tools use a moving column structure, and the processed workpiece does not move as much as possible, and the composite machining technology is used to reduce The number of card installations ensures the accuracy and consistency of the machining; the metal removal rate of large workpieces is generally very high, requiring the machine tool to have large torque, high speed and high feed rate.
The metal removal rate of large workpiece machining puts forward new requirements for cutting tools, and carbide cutting tools and high-speed steel cutting tools generally cannot meet this requirement. The tools manufactured by the powder metallurgy process can combine the best performance of these two tools to cut off the metal material faster.
Another big challenge for machining large workpieces is how to verify the machining results. Conventional measuring equipment cannot meet its requirements. Usually a portable contact measurement system is used, which is equipped with a small laser reflector that can move back and forth on the workpiece and feed back the collected size data to the measuring machine for analysis. The measuring range is up to tens of meters, which is very convenient to use.
On-site management during the machining of large workpieces is also very special. First of all, the handling of workpieces in the factory must be considered. Large forklifts and overhead cranes must be equipped to arrange the processes reasonably and minimize the number of handling. Since most of the measurement and machine tool debugging work is done on a large workbench, the machine tool operation must have a safety protection device and control system to ensure the safety of the operator.