Okuma’s MX-55X was the first vertical machining center we installed, but as we expanded our machines, we learned about the Thermo-Friendly Concept (TFC) and realized “this is good.” At that time, I handled turbine blades for thermal power generation, but even if I controlled the air conditioning, the workpiece dimensions shifted by 20-30 µm from the morning to the afternoon due to the expansion and contraction of the machine tool, and I had to adjust for that many times. With the installation of the MB-56V using TFC, the dimensional accuracy as expected was achieved, and the compensation work was greatly reduced.
Many parts of semiconductor and LCD manufacturing equipment are made of aluminum and have a thermal expansion coefficient twice that of iron, so they expand and contract by 24 µm per meter with a temperature difference of 1°C. The workpiece is machined from aluminum, but the flatness is particularly strict. For example, at the Takaono Plant, which handles large parts, the required flatness of the chamber is 10 µm or less. In order to secure this accuracy stably, we aim for one-half of the required accuracy.