Okuma VTM-2000YB

The Okuma VTM-2000YB is the largest of the VTM turn-mill machines compared here, turning parts up to 2,000 mm (78.74 in) in diameter and 1,400 mm (55.12 in) long. X and Y travel are both 1,600 mm (62.99 in) and Z is 1,400 mm (55.12 in). Okuma's table also lists B and C axes.

With 1,600 mm in both X and Y, the tool covers a square that takes in most of a 2,000 mm part. Off-centre pockets, pads and hole patterns can therefore be machined with linear moves, and the table only has to rotate to bring the outer corners of the part into range. Rapid traverse is 32 m/min (105 fpm) on X, Y and Z, quick for axes of this length. The rotary rapids are 19.5 min⁻¹ for B and 20 min⁻¹ for C.

Spindle speed is 4–300 rpm, with a 4–200 rpm variant shown in brackets. At this diameter those speeds still give a high cutting speed at the rim, and the 4 rpm floor is there for full-diameter facing and interrupted cuts in castings and fabrications. Small turned features near the centre are where the 300 rpm ceiling is felt.

Power is 30/22 kW (40/30 hp) on the 30 min and continuous ratings. That is the same figure the VTM-80YB lists for an 800 mm (31.50 in) part, so this machine is sized for reach, not for a bigger cut. The VTM-1200YB below it turns 1,200 mm (49.21 in) on 1,270 mm (50 in) of X with the same 32 m/min (105 fpm) rapids. The table for the VTM-2000YB gives no table load, torque or milling spindle figure, and on work of this size all three belong in the quotation.