Production Machine & Tool of Wichita Falls, Texas, is making a big investment in large-part capability with the purchase of a rotary-table horizontal boring mill with an innovative built-in U-axis contouring head.
The machine, a Giddings & Lewis RT 1250 U (the number refers to pallet size, in millimeters), permits changeover between the spindle and contouring head at the flip of a switch, says Linda Kieckhafer of MAG Americas. Giddings & Lewis is a MAG division. Contouring heads on boring mills are usually manual attachments. The RT 1250 U thus offers the potential for faster milling cycles and reduced labor, along with the versatility of the contouring head and its use of standard tools and an automatic toolchanger.
The unit, which Giddings & Lewis is now building for delivery, handles workpieces up to 60,000 lb — 15 times heavier than anything Production Machine & Tool has machined. The company will use this new capability to expand in current markets and win new applications, among them oil-drilling blowout preventers, fluid ends, and pump cases. Along with the new machine tool, the machine shop also will install new crane capacity.
A 75-hp motor powers the two spindles. The milling spindle has 1,000 mm (39.37 in) Z-axis travel, 2,500 mm (98.4 in) W-axis travel, and 6,744-lb continuous feed thrust. The boring spindle loads 50 taper tools with a maximum length of 750 mm (29.5 in), as well as programmable boring bars.
The contouring head’s slide stroke creates features up to 540 mm (21.3 in.) in diameter. The worktable rotates for access during contouring. The spindle has a Sandvik Coromant Capto C8 tool interface for rapid changeover. Coolant is pumped through the spindle at up to 300 psi, extending tool life.
The contouring head creates bottle bores, valve seats, seal faces, phonographic sealing services, O-ring grooves, straight or tapered threads, chamfers, external profiles, and other features.