Okuma MULTUS B750
Key Specifications
Tool Capacity
Rapid Traverse
max turning diameter
max machining length
main spindle speed
main spindle power
Overview
The Okuma MULTUS B750 is the flagship of Okuma's horizontal multitasking lineup, built for the largest and most complex shaft, cylinder, and housing work that demands both heavy turning and precision milling in a single setup. With a maximum turning diameter of 1,050 mm (41.3 in) and maximum machining length up to 6,000 mm (236.2 in) depending on bed configuration, the B750 operates in territory where few competitors can match its combination of size, capability, and accuracy.
The main turning spindle delivers 45/37 kW (60/50 hp) at up to 2,500 RPM with 1,200 Nm (885 ft-lb) of torque through an A2-11 spindle nose with 130 mm (5.12 in) bar capacity. The milling spindle runs up to 10,000 RPM with 37/30 kW (50/40 hp) through a Capto C8 interface. The B-axis swings 225 degrees (-30 to +195 degrees) with direct-drive and 0.001-degree increment for precise angular positioning on large components.
X-axis travel is 630 mm (24.8 in), Y-axis is 300 mm (11.8 in), and Z-axis extends to 6,000 mm (236.2 in) on the longest bed option. The generous Y-axis travel provides substantial off-center milling reach for complex features on large-diameter workpieces. Rapid traverse is 30 m/min on X and 24 m/min on Z. The standard ATC holds 40 tools with options up to 200 for complex jobs requiring extensive tool libraries.
Multiple steady rest positions support long-shaft work. An optional sub-spindle enables back-end machining on long parts. The optional lower turret adds simultaneous cutting for balanced roughing and multi-tool operations. Okuma's Thermo-Friendly Concept is essential on a machine with up to 6 meters of bed length, where thermal expansion can produce millimeter-level dimensional shifts without active compensation.
The MULTUS B750 competes with the WFL M120, Mazak Integrex e-800H, and DMG Mori NTX 3000. Pricing runs $1,000,000-$2,000,000+ new. Machine weight ranges from 30,000 to 50,000 kg depending on bed length. The machine targets oil and gas, power generation, aerospace, shipbuilding, and defense manufacturers that machine large, long, complex components.
Full Specifications
| Parameter | Value |
|---|---|
| Max Turning Diameter | Ø1,050 |
| Max Machining Length | Up to 6,000 mm (236.2 in) |
| Main Spindle Speed | 2,500 RPM |
| Main Spindle Power | 45/37 kW (60/50 hp) |
| Main Spindle Torque | 1,200 Nm (885 ft-lb) |
| Spindle Nose | A2-11 |
| Bar Capacity | 130 mm (5.12 in) |
| Milling Spindle Speed | 10,000 RPM |
| Milling Spindle Power | 37/30 kW (50/40 hp) |
| Milling Tool Interface | Capto C8 |
| B Axis Range | -30° to +195° (225° swing, 0.001° increment) |
| X Axis Travel | 630 mm (24.8 in) |
| Y Axis Travel | 300 mm (11.8 in) |
| Z Axis Travel | Up to 6,000 mm (236.2 in) |
| Tool Capacity | 40 (options: 60, 80, 120, 160, 200) |
| Rapid Traverse Rate | 40/40/40 |
| Sub Spindle | Optional |
| Lower Turret | Optional |
| Machine Weight | 30,000 - 50,000 kg (66,139 - 110,231 lb) |
| CNC Control | Okuma OSP-P500 |
| Speed Range | 11-2,000 |
| Standard Power | 37/30 |
| Okuma Global Repair Center | Charlotte, North Carolina |
| Inches | Metric |
| Spindle Nose Type | A2-11 |
Specifications sourced from okuma.com — verified 2026-03-28
Strengths & Limitations
Strengths
- Up to 6,000 mm machining length handles the longest shaft, cylinder, and spool components in oil and gas, power generation, and defense
- 1,200 Nm main spindle torque enables deep roughing on large-diameter forgings and castings in alloy steel and stainless
- 300 mm Y-axis travel provides the most off-center milling reach in the MULTUS B series for complex features on large parts
- Tool magazine scales to 200 positions for the extensive tool libraries needed on complex long parts with many different operations
- Capto C8 milling interface provides maximum rigidity for heavy boring and face milling at the scale this machine handles
- Thermo-Friendly Concept compensates for thermal expansion across up to 6 meters of bed length, maintaining end-to-end accuracy
Limitations
- Capital investment of $1,000,000-$2,000,000+ limits the machine to high-value applications in energy, aerospace, and defense
- Machine weight of 30,000-50,000 kg requires extensive foundation engineering with purpose-built reinforced concrete pads
- 2,500 RPM maximum main spindle speed produces low surface footage on smaller-diameter sections of large parts
- 24 m/min Z-axis rapid traverse adds significant repositioning time when working across the full 6-meter bed length
- OSP control managing multitasking operations across 6 meters of travel requires the most experienced programmers and advanced CAM
Best For
Frequently Asked Questions
01
A new MULTUS B750 starts around $1,000,000 for shorter bed configurations and can exceed $2,000,000 with the 6,000 mm bed, sub-spindle, lower turret, 200-tool magazine, and automation. Foundation engineering and installation add 10-15% to the total project cost.
02
Both are flagship multitasking machines for the largest components. The WFL M120 is Austrian-built and may offer slightly better simultaneous contouring precision. The Okuma B750 offers Thermo-Friendly Concept and typically lower pricing at comparable configurations. Both machines target the same high-end applications and have loyal user bases in their respective markets.
03
The B750 is available in multiple bed length configurations, with Z-axis travel options ranging from approximately 3,000 mm to 6,000 mm. The bed length is selected at purchase based on the longest workpiece the shop expects to machine. Longer beds increase machine weight, footprint, and cost.
04
Yes, the B750 is widely used for turbine shaft work in power generation. The machining length covers gas and steam turbine shafts, the 1,050 mm turning diameter handles the journal and bearing surfaces, and the B-axis milling spindle machines keyways, splines, and mounting features along the shaft length.
05
The B750 supports multiple programmable steady rests that position along the Z-axis to support long workpieces during turning. Steady rests are essential for long, slender shafts to prevent deflection and chatter. They can be repositioned programmatically during the machining cycle as the cutting point moves along the part.
Videos
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