Okuma MULTUS B750
Key Specifications
Tool Capacity
Rapid Traverse
standard chuck size
max machining diameter
max work length
spindle speed
Overview
The Okuma MULTUS B750 is the large-capacity end of Okuma's horizontal multitasking range, built for heavy shaft, cylinder and housing work that has to be both turned and milled without being moved between machines. The standard chuck is 15 in and maximum machining diameter is 1,050 mm (41.34 in).
Maximum work length is where the machine's scope really shows: 3,000 mm, 4,000 mm or 6,000 mm (118.11, 157.48 or 236.22 in) depending on bed configuration. That choice drives everything downstream — the machine occupies 9,130 mm of floor length in the shortest configuration, 10,555 mm in the middle one and 13,505 mm in the longest, at 3,532 mm to 3,797 mm wide and around 3,557 mm to 3,610 mm tall. Specifying the bed is a building decision as much as a machine decision, and it cannot be revisited later.
The main spindle runs 11~2,000 min⁻¹ on an A2-11 nose, driven by a 37/30 kW (50/40 hp) motor at the 30-minute and continuous ratings. The low ceiling and the very low 11 min⁻¹ minimum are the correct configuration for this class of work: at 1,050 mm diameter the surface speed at the outside of a part is substantial even at modest rpm, and the low end is what allows heavy facing and boring at full diameter where cutting speed must come down and torque has to carry the cut.
An A2-11 spindle nose is a large mount, which is what makes a 15 in chuck and the overhung mass of a heavy workpiece practical without the spindle mounting limiting the cut.
Rapids are 40 m/min (1,575 ipm) on all three linear axes. Consistent rapids across axes matter on beds this long, since traverse over several meters between operations is otherwise a significant share of the cycle.
Tool capacity is 40. On parts that combine heavy turning with milling, drilling and boring, that is a workable rather than generous library, and long jobs will still need planning around it.
A W specification adds a second spindle. The B750 suits oil and gas, power generation, marine and heavy industrial manufacturers machining large components complete.
Full Specifications
| Parameter | Value |
|---|---|
| Standard Chuck Size | 15 in |
| Max Machining Diameter | 1,050 mm (41.34 in) |
| Max Work Length | 3,000 / 4,000 / 6,000 mm (118.11 / 157.48 / 236.22 in) |
| Spindle Speed | 11~2,000 min⁻¹ |
| Spindle Nose | A2-11 |
| Spindle Motor | 37/30 kW (50/40 hp), 30 min/cont |
| Rapid Traverse Rate | 40/40/40 m/min (1,575/1,575/1,575 ipm) |
| Tool Capacity | 40 tools |
| Machine Dimensions | 9,130 × 3,532 × 3,557 mm (359.45 × 139.06 × 140.04 in); 10,555 × 3,532 × 3,607 mm (415.55 × 139.06 × 142.01 in); 13,505 × 3,797 × 3,610 mm (531.69 × 149.49 × 142.13 in) |
| Spec Extension | W (second-spindle specification) |
Specifications sourced from okuma.co.jp — verified 2026-08-09
Strengths & Limitations
Strengths
- Maximum work length of 3,000, 4,000 or 6,000 mm (118.11, 157.48 or 236.22 in) covers heavy shaft and cylinder work few multitasking machines reach
- 15 in standard chuck with 1,050 mm (41.34 in) maximum machining diameter for large housings and flanged components
- A2-11 spindle nose is a large mount, which is what makes a 15 in chuck and a heavy overhung workpiece practical without the mounting limiting the cut
- The 11 min⁻¹ minimum spindle speed allows heavy facing and boring at full diameter where cutting speed must come down and torque carries the cut
- 37/30 kW (50/40 hp) motor at the 30-minute and continuous ratings backs those low-speed cuts
- Rapids of 40 m/min (1,575 ipm) on all three linear axes matter on beds several meters long
Limitations
- Bed choice is a building decision: 9,130 mm of floor length in the shortest configuration, 10,555 mm in the middle and 13,505 mm in the longest, at up to 3,797 mm wide and around 3,610 mm tall
- That bed configuration cannot be revisited after order
- The 2,000 min⁻¹ spindle ceiling rules out small-diameter high-surface-speed work
- Tool capacity of 40 is workable rather than generous for parts combining heavy turning with milling, drilling and boring
- 30 kW continuous is the number to plan sustained cuts against, not the 37 kW 30-minute rating
Best For
Frequently Asked Questions
01
Maximum work length is 3,000 mm, 4,000 mm or 6,000 mm (118.11, 157.48 or 236.22 in). That choice drives the installation: the machine occupies 9,130 mm of floor length in the shortest configuration, 10,555 mm in the middle one and 13,505 mm in the longest, at 3,532 mm to 3,797 mm wide and around 3,557 mm to 3,610 mm tall. It cannot be revisited later.
02
Maximum machining diameter is 1,050 mm (41.34 in), with a 15 in standard chuck. That covers large housings, cylinders and flanged components, and it is the reason the machine uses an A2-11 spindle nose rather than a smaller mount.
03
Because at 1,050 mm diameter the surface speed at the outside of a part is substantial even at modest rpm. The more important end of the 11~2,000 min⁻¹ range is the low one: 11 min⁻¹ is what allows heavy facing and boring at full diameter, where cutting speed must come down and the 37/30 kW (50/40 hp) motor has to carry the cut on torque.
04
It is a large mount, and on a machine handling 1,050 mm diameters that matters. It carries a 15 in chuck and absorbs the overhung mass of a heavy workpiece without the spindle mounting becoming the limiting element in the cut.
05
Tool capacity is 40, which is workable rather than generous. Parts that combine heavy turning with milling, drilling and boring consume tooling quickly, so long jobs still need planning around the magazine — particularly where the same setup has to cover roughing and finishing.
Videos
OKUMA CORPORATION JAPAN
aks okuma
Okuma America Corporation
Dale Quint
JS PRECISION CO
Community Discussions
Pricing and buying discussion — What are your experience with okuma machines? :
Community discussion — Asking advice for a fresh cut- switching from okuma multus to ...
Community discussion — Okuma...Love or Hate? : r/Machinists - Reddit
Community discussion — Can you recommend a G-Code simulator? : r/Machinists - Reddit
Links to community discussions. Summaries are editorial — visit the original thread for full context.
Comparisons
Related Machines
Mazak Integrex i-200
Okuma Multus B250II
DMG Mori CTX gamma 2000 TC
DMG Mori NTX 2000
DN Solutions SMX 3100ST
