The Okuma LB4000 EX III is a big-bore, box-way horizontal turning center built for heavy, large-diameter turning with the rigidity Okuma is known for. This 2025 example in the 1500 (59 in.) bed length pairs a 26.38 in. swing, 18.9 in. max turning diameter, and a 4.41 in. (112mm) big-bore A2-11 spindle turning to 3,000 RPM on a 50 HP PREX motor, with live tooling to 6,000 RPM, full C-axis, and a Y-axis (+/-2.76 in.) for off-center milling, drilling, and contouring. Running the Okuma OSP-P500L control, it comes equipped with a 12-station turret, a 12 in. Kitagawa 3-jaw power chuck, an NC self-traveling tailstock, an SMW K3-Z automatic steady rest, and a Chipblaster high-pressure coolant unit - a complete done-in-one turn-mill cell.
Compared with the smaller LB3000 EX III in the same SPACE TURN line, the LB4000 EX III steps up to a larger 18.9 in. turning diameter and a bigger 112mm big-bore spindle, giving it the capacity for larger shafts, flanges, and heavy oilfield-style work while sharing the box-slant-bed rigidity and thermal stability of the EX III series. Configured here with live tooling, a Y-axis, the OSP-P500L control, and an automatic steady rest, this machine handles long, heavy workpieces complete in a single setup.