The capacity of the machine in the X axis is 1,200 mm, with 800 and 500 mm available in Y and Z respectively. Supporting a table working area of 1,200 by 800 mm, the mechanical design focus was on planer-style symmetric construction to maximise rigidity and achieve tight tolerances based on hardened and ground tool steel slideways. The machine also incorporates Mitsui Seiki’s latest ‘sliding mechanism’ development, where contact slideway elements not only enhance acceleration but minimise stick-slip, which enables claims for the Z-axis having some six times greater static rigidity than more conventional designs.
Thermal compensation is deployed to reduce any influence of temperature fluctuations or temperature-generated displacement by 60% thanks to integrated sensors housed on the machine face plate and within the spindle. Further gains are made with the MAMS multi-sensor system on the Z-axis, which is said to reduce thermal growth and deflection by 30%. In addition, to help maintain stable rates of axis feed within 0.0001 mm, a centralised cooling system is incorporated within the sideway, as well as the core of each ballscrew.
The Mitsui Seiki PJ812 has direct-drive spindle options of 50 taper, 30 kW, 10,000 rpm, up to 18 kW, 30,000 rpm with 40 taper. Rapid traverse rate are 24 m/min and a 40 tool magazine is standard. Control is by Fanuc 31iM-B.
