The ST-55 turning center from Haas Automation features twin-chuck capabilities, a high-torque spindle and a 12.5"- (318-mm) diameter through-bore. The turning center is well-suited for machining heavy pipes and fittings, large couplers and long rollers, the company says.
The turning center has a maximum cutting capacity of 25.5" × 80" (648 × 2,032 mm), with swings of 34.5" (876 mm) over the front apron and 25.5" (648 mm) over the cross-slide. A servo-driven tailstock (MT5 taper) is standard, and a rest provision is available for supporting long shafts.
A 55-hp (41-kW) vector dual-drive unit powers the spindle through a two-speed gearbox to provide 2,100 foot-pounds (2,847 Nm) of torque in low gear. High gear supports a spindle speed of 1,000 rpm. Both front and rear A1-20 spindle noses accept a variety of aftermarket large-diameter manual and pneumatic chucks, and a heavy sheet metal enclosure provides protection from chips and coolant during machining.
The machine is equipped with a hydraulically clamped, 12-station, bolt-on-style tool turret that accepts 7.25" (184 mm) split boring bar holders, as well as BOT toolholders. An optional hybrid BOT/VDI turret is available. Standard equipment includes rigid tapping, a color remote jog handle, a 15" color LCD monitor and built-in USB connectivity. High-productivity options include a belt-type chip conveyor, high-torque live tooling with C axis and high-pressure coolant systems.
The turning center is designed for jobs common in oilfield work. Haas’s Intuitive Programming System features built-in threading and rethreading cycles for both straight and tapered threads.