Machine Comparison
Okuma MULTUS B550 vs Okuma MULTUS B750
Okuma vs Okuma · Mill-Turn Machines
Summary
The Okuma MULTUS B550 and the Okuma MULTUS B750 share most of their published figures: a 37/30 kW (50/40 hp) spindle, an A2-11 spindle nose, 40 tools and 40/40/40 m/min rapid traverse. The difference is part diameter and the speed range that goes with it.
The Okuma MULTUS B750 turns up to 1,050 mm (41.34 in) against 830 mm (32.68 in), and its spindle runs from 11 rpm to 2,000 rpm, which suits slow facing cuts on large rings and flanges. The Okuma MULTUS B550 runs from 30 rpm to 3,000 rpm, giving it the higher top speed for smaller diameters.
Specifications Comparison
| Specification | Okuma MULTUS B550 | Okuma MULTUS B750 |
|---|---|---|
| Max Turning Diameter | 830 mm (32.68 in) | 1,050 mm (41.34 in) ▲ |
| Max Spindle Speed | 30–3,000 rpm ▲ | 11-2,000 rpm |
| Spindle Power | 37/30 kW (50/40 hp) | 37/30 kW (50/40 hp) |
| Spindle Taper / Nose | A2-11 | A2-11 |
| Tool Capacity | 40 tools | 40 tools |
| Rapid Traverse | 40/40/40 m/min (1,574/1,574/1,574 ipm) | 40/40/40 m/min (1,575/1,575/1,575 ipm) |
Advantages
Okuma MULTUS B550
- 3,000 rpm top spindle speed against 2,000 rpm
- Described for large chucking parts up to 830 mm (32.68 in), where the larger turning diameter would go unused
Okuma MULTUS B750
- 1,050 mm (41.34 in) maximum turning diameter against 830 mm (32.68 in)
- Spindle range starts at 11 rpm against 30 rpm, for slow facing cuts on large diameters
Verdict
The choice comes down to diameter. Rings, flanges and housings beyond 830 mm (32.68 in) need the Okuma MULTUS B750 and its 1,050 mm (41.34 in) turning diameter, and its 11 rpm low end suits large facing cuts. Work that fits within 830 mm (32.68 in) is better matched to the Okuma MULTUS B550, which has the same 37/30 kW (50/40 hp) spindle and 40 tools but reaches 3,000 rpm against 2,000 rpm.