Large special-purpose machines are tools optimized in terms of their processing functions in
compliance with the material, shape and machining details of large workpieces. Mitsubishi Heavy
Industries, Ltd. (MHI) is one of the world's few machine tool manufacturers handling large
special-purpose machines, and its Machine Tool Division provides products to those industrial
sectors manufacturing large-sized parts such as for power system equipment (power plants), aircraft
and construction machinery, thereby gaining a high reputation. In addition, MHI is well-known as a
leading global manufacturer of power system equipment and aircraft, and this division has
supported its in-house manufacturing sectors for more than 20 years, thereby accumulating
abundant experience, technologies and expertise concerning machining of large workpieces.
This paper introduces a large special-purpose machine to process turbine rotors and gas
turbine rotor disks as key components of power system equipment, i.e., side-entry processing
machine, chain broaching machine and disk coupling grinder.