Grob G550

The GROB G550 is a 5-axis universal machining center with 800 x 1,020 x 970 mm of X/Y/Z travel, a 770 mm table and a 900 mm interference diameter. What sets it apart in GROB's table is the spindle list: ten versions across two interfaces, where the smaller G350 is listed with HSK-A63 only.

Five versions use HSK-A63: 83 Nm at 12,000 rpm, 206 Nm at 16,000 rpm, 47 Nm at 18,000 rpm, 47 Nm at 21,000 rpm and 63 Nm at 30,000 rpm. Five use HSK-A100: 265 Nm at 13,000 rpm, 575 Nm at 9,000 rpm, 340 Nm at 10,000 rpm, and 340 Nm and 344 Nm at 6,000 rpm. A spread from 47 Nm to 575 Nm means one frame can be a fast aluminium machine or a torque machine for steel and titanium, and that decision is made at order. The table marks none of the ten as standard and gives no power figures, so the quotation has to settle both.

The table carries 800 kg without a pallet and 700 kg with one. Rapid traverse is 65 m/min in X, 50 m/min in Y and 80 m/min in Z, with a chip-to-chip time of 2.8 s (t1, according to VDI 2852) and positioning accuracy of 0.006 mm in X, Y and Z. The A axis swivels 230 degrees and the B axis turns 360 degrees.

Tool length follows the magazine. The single disk-type magazine (HSK-A63) takes 465 mm. The double disk-type magazine takes 465 mm in the bottom disk, 280 mm in the top disk and 700 mm over both disks. Machine weight is 24,800 kg, or 27,500 kg with the pallet changer, and the control is SIEMENS 840D sl or HEIDENHAIN TNC 640 with GROB4Pilot.