Big parts are big business, and machine shops need large-capacity machines to handle the big jobs now commonly booked by customers that work in oil-and-gas exploration, alternative energy, mining, and aerospace industries.
The ST-55 from Haas Automation Inc., is a heavy-duty, large-bore turning center that is extremely rigid, highly accurate, and very thermally stable. The machine’s twin-chuck capability, high-torque spindle, and 12.5 in. (318 mm) diameter through-bore recommend it for machining heavy pipes and fittings, large couplers, and long rollers. It has a maximum cutting capacity of 25.5 in. x 80 in. (648 x 2032 mm), with swings of 34.5 in. (876 mm) over the front apron and 25.5 in. (648 mm) over the cross slide. A servo-driven tailstock (MT5 taper) is standard, and a steady rest provision is available for additional support of long shafts.
A 55-hp (41-kW) vector dual-drive unit powers the ST-55’s spindle through a Haas-built two-speed gearbox to provide 2100 ft-lb (2847 Nm) of torque in low gear. High gear provides a maximum spindle speed of 1000 rpm. Both front and rear A1-20 spindle noses accept a variety of aftermarket large-diameter manual and pneumatic chucks.
The ST-55 comes equipped with a “massive,” hydraulically clamped 12-station bolt-on style tool turret that accepts 7.25 in. (184 mm) split-boring bar holders, as well as standard BOT toolholders.
An optional hybrid BOT/VDI turret is available, too.
Standard equipment includes rigid tapping, a color remote jog handle, a 15-in. color LCD monitor, and built-in USB connectivity. Available high-productivity options include a belt-type chip conveyor, high-torque live tooling with C axis, high-pressure coolant systems, and much more.
To tackle the types of jobs common in oilfield work, the ST-55 is available with Haas Automation’s proprietary Intuitive Programming System, which includes built-in threading and rethreading cycles for both straight and tapered threads – a function not available with any other machine, according to the developer.
The ST-55 features a heavy sheet metal enclosure that provides complete protection from chips and coolant during machining. A pair of wide sliding doors provides unobstructed access to the front chuck and main work area, both from the front and the top, allowing easy overhead loading.
Also, the rear chuck area is fully enclosed during machining, but a wide sliding door and swinging end panel provide complete access from the front and top, simplifying chuck installation and adjustment, and making it easy to load pipe using an overhead crane. Unlike some competing machines, it’s not necessary to remove sheet metal panels or modify the enclosure to handle drill pipe.
Haas Automation will be exhibiting 18 machines at IMTS 2014, and seven more Haas machines will be on display by other vendors.