The machining centre PJ812 provides positioning accuracy and repeatability of +/- 1µm. (Source: MItsui Seiki) USA – The new Mitsui Seiki PJ812 precision profile centre is a three-axis CNC vertical jig mill engineered to perform high-precision contour machining and ultra precise boring of components with critical tolerances. The machining centre is ideal for processing parts for the mould and die, optical, aerospace and medical industries. According to the company, PJ812 provides positioning accuracy and repeatability of +/- 1µm. A thermal compensation system employs sensors on the machine faceplate and inside the spindle to minimise the effects of temperature changes on part accuracy and cut temperature-generated displacement by 60%. This system also reduces Z-axis thermal growth and deflection by 30%. Cooling systems for slide way lubrication and ball screw cores stabilise axis feed precision Mechanical design features that maximise machine rigidity and accuracy include hardened and ground tool steel box sideways as well as contact elements that enhance acceleration, reduce stick-slip, and allow for feed accuracy of 0.1 µm. Another proprietary engineering detail improves the static rigidity of the Z-axis to more than six times that of conventional Z-axis arrangements, Mitsui adds. The machining centre spindle choices include 10,000 RPM with 50-taper with 30/15 kW (40/20 hp) direct drive motors and up to 30,000 RPM, 18/15 kW (24/20 hp) with 40-Taper. X-, Y- and Z-axis travels are 1,200 mm, 800 mm and 500 mm respectively. The machine table can accommodate a maximum load of 1,500 kg on its 1,200 mm x 800 mm work surface. Overall machine footprint is 4,720 mm by 3,000 mm. A 40-tool capacity ATC is standard. The fully enclosed machine enclosure allows for complete containment of chips and coolant, while affording excellent work loading and set up ergonomics. The PJ812 possesses an energy saving circuit that reduces electric power consumption by up to 90% and compressed air consumption by up to 40%, the company adds. The latest Fanuc 31iM-B CNC is equipped with a new HMI and a 500mm LCD touch screen for ease of operation for set up and at-machine programming.