ROMI G 550
Image: romi.com, Romi
Key Specifications
Max Spindle
Spindle Power
Max Turn Length
swing over z axis cover
max turning diameter
x axis travel
How much does the ROMI G 550 cost?
Price estimate
We do not have a price for the ROMI G 550 that we can stand behind, so we show no number. Configuration, options and installation move the final price a long way: a quote is the reliable figure.
Overview
The ROMI G 550 is a heavy two-axis turning center for chuck and shaft work up to 550 mm (22 in) in diameter and 1,300 mm (51 in) in cutting length. It carries a 45.7 hp / 33.6 kW main motor and, unlike the lighter GL machines, runs on hardened and ground flat and prismatic guideways instead of linear guides. This is the fixed-tool version; the G 550M is the same machine with a driven-tool turret.
Three spindle arrangements are listed. The A2-8” headstock has a 104 mm (4.1 in) thru-hole and runs from 2 to 2,500 rpm with 680 Nm (502 lb-ft). The A2-11” headstock opens the thru-hole to 142 mm (5.6 in), runs to 2,000 rpm and gives 780 Nm (575 lb-ft). The third is specific to the G 550: the A2-11” headstock with a ZF reduction gearbox, whose low range of 6 to 630 rpm multiplies torque to 2,310 Nm (1,704 lb-ft). For large-diameter roughing in tough steels that gearbox is the configuration to ask about.
The T type turret has 12 stations on a Romi disc and takes 32 x 32 mm (1 1/4 x 1 1/4 in) square tools and Ø 50 mm (2 in) boring bars, a heavier tool section than the 25 x 25 mm (1 x 1 in) of the G 550M turret. X travel is 280 mm (11 in), Z travel 1,340 mm (53 in), with rapids of 20 m/min in X and 24 m/min in Z.
Romi fits a tailstock whose body positions automatically over 1,143 mm (45 in) and locks hydraulically. Its 120 mm (4.7 in) quill is hydraulic, with 130 mm (5.1 in) of travel and a built-in MT 5 live center. The control is a Siemens Sinumerik 828D. Floor space is 6,320 x 2,310 mm (249 x 91 in) without chip conveyor, weight 8,780 kg (19,360 lbs) and installed power 50 kVA.
Full Specifications
| Parameter | Value |
|---|---|
| Swing Over Z Axis Cover | 685 mm (27 in) |
| Max Turning Diameter | 550 mm (22 in) |
| Max Turning Length | 1,300 mm (51 in) |
| X Axis Travel | 280 mm (11 in) |
| Z Axis Travel | 1,340 mm (53 in) |
| Spindle Nose | ASA A2-8” or A2-11” |
| Spindle Bore | 104 mm (4.1 in) with A2-8”; 142 mm (5.6 in) with A2-11” |
| Spindle Front Bearing Inner Diameter | 150 mm (5.9 in) with A2-8”; 200 mm (7.9 in) with A2-11” |
| Max Spindle Speed | 2 to 2,500 rpm with A2-8”; 2 to 2,000 rpm with A2-11” |
| Spindle Speed with Gearbox | A2-11” with ZF reduction gearbox: range I 6 to 630 rpm; range II 2 to 2,000 rpm |
| Spindle Torque | 680 Nm (502 lb-ft) with A2-8”; 780 Nm (575 lb-ft) with A2-11”; 2,310 Nm (1,704 lb-ft) with A2-11” and ZF reduction gearbox (S2 - 30 min rating) |
| Rapid Traverse X | 20 m/min |
| Rapid Traverse Z | 24 m/min |
| Turret Stations | 12 |
| Turret Tooling | T type turret, ROMI |
| Turret Tool Section | 32 x 32 mm (1 1/4 x 1 1/4 in) |
| Turret Boring Bar Diameter | Ø 50 mm (2 in) |
| Tailstock Body Travel | 1,143 mm (45 in) |
| Tailstock Quill Travel | 130 mm (5.1 in) |
| Tailstock Quill Diameter | 120 mm (4.7 in) |
| Tailstock | Automatic body positioning, hydraulic body fixing, hydraulic quill |
| Tailstock Quill Taper | MT 5 (built-in) |
| Spindle Motor Power | 45.7 hp / 33.6 kW (S2 - 30 min. rating) |
| Power Requirement | 50 kVA |
| Floor Space | 6,320 x 2,310 mm (249 x 91 in) without chip conveyor |
| Machine Weight | 8,780 kg (19,360 lbs) |
| CNC Control | Siemens Sinumerik 828D |
Specifications sourced from romi.com — verified 2026-10-04
Strengths & Limitations
Strengths
- Optional ZF reduction gearbox on the A2-11” headstock gives 2,310 Nm (1,704 lb-ft) in a 6 to 630 rpm range
- 45.7 hp / 33.6 kW main motor
- Spindle thru-hole of 142 mm (5.6 in) with the A2-11” nose
- T type turret for 32 x 32 mm (1 1/4 x 1 1/4 in) tools and Ø 50 mm (2 in) bars
- Programmable tailstock with hydraulic quill and built-in MT 5 live center
Limitations
- Fixed tools only; milling and drilling off-centre need the G 550M
- Top speed is 2,500 rpm with A2-8” and 2,000 rpm with A2-11”
- Rapids of 20 m/min in X and 24 m/min in Z are modest
- Needs 6,320 x 2,310 mm (249 x 91 in) of floor before the chip conveyor
Best For
Frequently Asked Questions
01
The turret. The G 550 has a T type turret with a Romi disc for fixed tools, 32 x 32 mm (1 1/4 x 1 1/4 in) shanks and a maximum cutting diameter of 550 mm (22 in). The G 550M has a BMT-75 turret for fixed and driven tools and cuts up to 530 mm (21 in). The ZF gearbox headstock is listed for the G 550 only.
02
A low range. With the A2-11” headstock and ZF reduction gearbox, range I runs from 6 to 630 rpm and range II from 2 to 2,000 rpm, and the power graph shows 2,310 Nm (1,704 lb-ft). The direct-drive A2-11” headstock gives 780 Nm (575 lb-ft).
03
The spindle thru-hole is 104 mm (4.1 in) with the A2-8” nose and 142 mm (5.6 in) with the A2-11” nose. Front bearing inner diameters are 150 mm (5.9 in) and 200 mm (7.9 in), which indicates how heavily built the two cartridges are.
04
A programmable one. The body positions automatically along 1,143 mm (45 in) of travel and is fixed hydraulically. The quill is 120 mm (4.7 in) in diameter with 130 mm (5.1 in) of hydraulic travel and a built-in MT 5 live center. A hydraulic follow rest is offered for slender shafts.
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