Haas ST-40Y

The Haas ST-40Y is the largest Y-axis turning center Haas builds. A 381 mm (15.0 in) chuck on an A2-8 spindle nose with a 117.3 mm (4.62 in) bore gives 102 mm (4.00 in) bar capacity, and maximum part swing is 902 mm (35.5 in). Usable cutting envelope is 699 mm (27.50 in) in diameter with the BMT75 turret by 1,118 mm (44.0 in) long, so large flanges, housings and long shafts are both within reach.

The spindle runs through a 2-speed gearbox to 2,400 rpm at 29.8 kW (40.0 hp), producing 1,898.0 Nm (1,400.0 ft-lbf) at 150 rpm. That torque figure, not the horsepower, is what defines the machine. At 1,400 ft-lbf it will take deep cuts on large-diameter forgings and castings in tough material where a higher-revving spindle would simply stall. An XP option raises this to 41.0 kW (55.0 hp) and 2,847.0 Nm (2,100.0 ft-lbf) at 150 rpm for shops whose work justifies it. The low 2,400 rpm ceiling is the expected consequence of that gearing and chuck mass.

Y travel is ±76 mm (±3.0 in) — more offset than the smaller ST machines, which matters because features on a 699 mm part sit further from centerline. Live tooling runs to 4,000 rpm on the 12-station BMT75 turret, with the C-axis positioning to ±0.01° and held by a 546 mm (21.5 in) brake at 610 Nm (450 ft-lbf). Turret index time is 2 s.

Thrust capability tracks the size of the machine: 24,465 N (5,500 lbf) in X and 40,034 N (9,000 lbf) in Z. The tailstock takes an MT5 center over 1,067 mm (42.0 in) of travel at up to 13,345 N (3,000 lbf), which is what makes the full 1,118 mm cutting length usable on slender shaft work rather than nominal.

Rapids are 12.0 m/min (472 ipm) in X and Y and 18.0 m/min (710 ipm) in Z — modest, reflecting the moving mass. Coolant capacity is 360 L (95 gal) and shipping weight is 10,378 kg (22,880 lb) in the export crate. It suits oil and gas, heavy equipment and aerospace shops turning large components that also need milled features.