Okuma MULTUS B400
Key Specifications
Max Turning Diameter
Max Turning Length
Main Spindle Speed
Main Spindle Motor
Sub-Spindle Speed
Milling Spindle Speed
Overview
The Okuma MULTUS B400 is a mid-size mill-turn machining center offering expanded workpiece capacity over the B200, with a maximum turning diameter of 660 mm and the same B-axis multi-tasking architecture. It combines turning, milling, drilling, tapping, and contouring in a single machine, reducing part handling and eliminating accumulated setup errors.
Equipped with a tilting B-axis milling spindle, the MULTUS B400 achieves true 5-axis simultaneous cutting on complex compound surfaces. A high-torque turning spindle handles aggressive roughing in difficult materials, while the high-speed milling spindle enables precision finishing passes with excellent surface finish results.
The integrated sub-spindle mirrors the capability of the main spindle, enabling complete machining of both ends of a workpiece in one program. This makes the MULTUS B400 particularly effective for shaft-type components and large flanges that require precision features on both faces.
With Okuma's OSP-P300S control, operators benefit from advanced functions including the Collision Avoidance System, Machining Navi M for milling chatter suppression, and SERVONAVI for optimized servo tuning. The MULTUS B400 is a go-to solution for aerospace, energy, and heavy industrial applications requiring high-capacity multi-tasking.
Full Specifications
| Parameter | Value |
|---|---|
| Max Turning Diameter | 660 mm (26.0 in) |
| Max Turning Length | 1,259 mm (49.6 in) |
| Main Spindle Speed | 20 – 3,500 rpm |
| Main Spindle Motor | 22 / 26 kW (30 / 35 HP) |
| Sub-Spindle Speed | 20 – 3,500 rpm |
| Milling Spindle Speed | 20 – 10,000 rpm |
| Milling Spindle Motor | 22 / 26 kW (30 / 35 HP) |
| B-Axis Range | –30° to +210° |
| Y-Axis Travel | ±125 mm |
| Rapid Traverse (X/Y/Z) | 30 / 30 / 40 m/min |
| Chuck Size (Main/Sub) | 315 mm / 254 mm |
| Bar Capacity | 102 mm (4.0 in) |
| CNC Control | Okuma OSP-P300S |
| Machine Weight | Approx. 21,000 kg (46,300 lb) |
| Model | MULTUS B400-WDiscontinued Model |
| Brand | OKUMA |
| Type | 5-Axis or More CNC Lathes |
| Axis8chuck Size15bar Capacity4power40 Hpmax Rpm10000 Rpm | Turning Dia27.9"Swing27.9"Machining Length61"TailstockNoControlCNC (OSP-200L) |
| Axis | 8 |
| Chuck Size | 15" |
| Bar Capacity | 4" |
| Power | 40 hp |
| Max Rpm | 10,000 RPM |
| Turning Dia | 27.9" |
| Swing Over Bed | 27.9" |
| Machining Length | 61" |
| Tailstock | No |
| Cnc Control | CNC (OSP-200L) |
| Listings | (6) |
| Lathes Cnc | 5 photosYear: 2007 |
| 13 Photos | Year: 2008 |
| 23 Photos | Video |
| 6 Photos | Year: 2008 |
| 10 Photos | Year: 2008 |
| 5 Photos | Year: 2007 |
Specifications sourced from machinetools.com — verified 2026-03-28
Strengths & Limitations
Strengths
- Large 660 mm turning diameter accommodates big flanges, housings, and aerospace structural parts
- B-axis milling spindle delivers true 5-axis simultaneous machining for complex contours
- Integrated sub-spindle enables complete done-in-one machining of both workpiece ends
- Rigid construction handles titanium and Inconel roughing without vibration or deflection
- Advanced CAS collision avoidance protects the machine during complex multi-axis programs
Limitations
- Premium price point requires high-value, complex workpieces to justify investment
- Large footprint and significant machine weight demand thorough site preparation
- Programming multi-axis mill-turn cycles requires experienced CAM and CNC expertise
Best For
Frequently Asked Questions
01
The B400 offers a significantly larger maximum turning diameter of 660 mm versus 350 mm on the B200, and a longer turning length of 1,259 mm versus 545 mm, making it suited for larger workpieces in aerospace and energy applications.
02
The MULTUS B400 accepts bar stock up to 102 mm (4.0 in) in diameter, allowing production of medium-to-large turned parts directly from bar in a bar feeder configuration.
03
Yes. The MULTUS B series supports optional grinding spindle attachments, enabling hard turning and grinding in the same setup, which is valuable for finishing hardened components to tight tolerances.
04
The MULTUS B400 uses Okuma's OSP-P300S control with multi-axis coordination, Collision Avoidance System, Machining Navi, and SERVONAVI for servo optimization across all axes.
05
Yes. The high-torque spindles, rigid structure, and advanced thermal compensation make the MULTUS B400 well-suited for titanium, Inconel, and other aerospace alloys when used with appropriate tooling strategies.
Videos
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Links to community discussions. Summaries are editorial — visit the original thread for full context.
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