GBCTN-500 CNC 6 Axis Hobbing Machine
The GBCTN-500 CNC 6 Axis Hobbing Machine is the flagship of the GBC vertical hobbing range, handling workpieces up to Φ500 mm and module M14 with a Φ450 mm direct-drive table generating 2000 Nm torque. It is engineered for heavy-industry gear manufacturers producing wind-turbine main gears, large marine ring gears, and industrial mill-drive components.
GBCTN-500 CNC 6 Axis Hobbing Machine — Flagship Heavy-Duty Platform for Φ500 mm Gear Production
The GBCTN-500 represents the pinnacle of GBC's CNC 6 axis hobbing machine development — sized and specified for the most demanding large-module gear production tasks. With a maximum workpiece diameter of Φ500 mm, M14 module capability, and a Φ450 mm direct-drive table producing 2000 Nm torque, the GBCTN-500 operates in the performance tier of machines costing significantly more from European builders. The 40 KVA main power supply and BT#50 spindle nose (Φ200 mm x 240 mm hob capacity) are configured to remove M14 module material from Φ500 mm alloy-steel blanks in a single climb-cut pass. Explore the complete family at the GBC CNC Hobbing Machine hub.
Machine Bed, Spindle & Table — Engineered for M14 Loads
The GBCTN-500's machine body is cast in extra-heavy Meehanite iron with a reinforced cross-rib pattern optimised by finite-element analysis for M14 module cutting forces. The BT#50 spindle nose accommodates hobs up to Φ200 mm x 240 mm, and the 240 mm shift travel ensures even wear distribution across the hob face on long batch runs. The Φ450 mm direct-drive table — the largest in the GBC range — eliminates the positional errors inherent in worm-driven tables, providing the angular precision needed for M14 gear pitch accumulation errors within DIN 6. The 40 KVA power class, Max.500 rpm hob spindle, and S1=52.5 Nm / S3=118 Nm torque support aggressive cutting data that cut cycle times by 20-30% versus equivalent conventional-drive machines.
❖ Key Features
️ High-Rigidity Heavy-Machining Bed
FEA-optimised Meehanite iron, stress-relief annealed, all guideways hardened and precision-scraped — provides 80+ Hz natural frequency under M14 interrupted-cut excitation.
Stable Adjustable Rolling Hob-Head Spindle
BT#50 spindle nose with angular-contact bearing pre-load adjust; supports Φ200 mm hobs for M14 module; runout <3 um maintained through full hob-life cycle.
High-Torque Large-Diameter Ultra-Precision Table
Φ450 mm direct-drive table at 2000 Nm continuous torque — the highest in the GBC range — supports full-depth M14 cuts without table stall.
High-Speed Direct-Drive Rotary Table
Max. 100 rpm table rotation for rapid traverse and positioning; direct-drive eliminates angular-position error accumulation across long production sequences.
Stainless Mirror Chip Trough
Extra-wide polished stainless trough handles high chip volume of M14 cuts, with steep-angled walls preventing chip bridging at the conveyor inlet.
️ FANUC 0i-MF Plus & 40 KVA Supply
Highest power class in the GBC series; nano-interpolation, full Ethernet/DNC, and optional data-server NC program management for batch production of 100+ workpiece families.
Industries & Applications
️ Wind Energy — Main & Rotor Shaft Gears
Φ400-500 mm main shaft pinions and rotor-bearing drive gears for 3-6 MW turbine class, where M10-M14 module and DIN 5 accuracy are standard specifications.
Cement & Mill Drive Systems
Large-diameter drive pinions and girth-gear mating pinions for kiln and ball-mill drives; modules up to M14 machined in a single pass.
⚓ Heavy Marine & Offshore Gearboxes
Thruster gearbox pinions, azimuthing-drive helical gears, and wave-energy converter reduction sets requiring 100% dimensional certification.
Locomotive & Heavy Rail
Traction motor pinion shafts and bogie final-drive gear sets for 25-tonne-axle-load freight locomotives and high-power metro cars.
Large Special Gearbox OEM
Custom gear pairs for extruder drives, steel-rolling mill main drives, and petrochemical compressor gear units requiring individual process qualification.
Technical Specifications
| Parameter | GBCTN-500 Specification |
|---|---|
| Max. Workpiece (OD x Module) | Φ500 mm x M14 |
| Max. Helix Angle | +35° / -45° |
| Table (C Axis) Diameter | Φ450 mm |
| Spindle Nose Taper | BT#50 |
| Max. Hob Size (OD x Length) | Φ200 mm x 240 mm |
| Max. Hob Shift Travel | 240 mm |
| Hob Spindle (B Axis) | Max. 500 rpm | S1=52.5 Nm, S3=118 Nm |
| Table Rotation (C Axis) | Max. 100 rpm | Direct-drive 2000 Nm |
| Radial Feed (X Axis) | Max. 5000 mm/min | 310 mm (90-400 mm) |
| Tangential Feed (Y Axis) | Max. 1500 mm/min | 240 mm (0-240 mm) |
| Axial Feed (Z Axis) | Max. 3800 mm/min | 365 mm (400-765 mm) |
| Helix Angle Speed (A Axis) | Max. 200 deg/min | +35° / -45° |
| Hyd. Tailstock (U Axis) | Max. 5000 mm/min | 380 mm (250-630 mm) |
| Main Power | 40 KVA |
| Control System | FANUC 0i-MF Plus |
| Floor Space (L x W x H) | 4500 x 3700 x 3050 mm |
| Machine Weight | 14.0 ton |
Standard Configuration & Optional Accessories
Standard Configuration
- C-axis direct-drive motor with backup rotary encoder
- Servo tailstock
- Mist cutting and machine-body cleaning device
- Tool pre-setter
- Post-cut spindle protection function
- Chip-scraper system (heavy-duty)
- Internal cooling device
- Mist centrifugal collector
- Hydraulic system
- Auto-lubrication device
- Pneumatic device
- Control cabinet with air conditioner
- Three-colour indicator light
- Mirror stainless chip-trough design
Optional Accessories
- Dry-cutting function
- End-face deburring device
- Second-cut device
- Servo tailstock upgrade
- Oil-mist electrostatic collector
- Dry-cut high-efficiency collector
- Magnetic contact detection
- Cutting fluid cooling system (high-flow)
- B-type new energy regenerative protection
- Large-diameter fixture and chuck
- Hobbing cutters M10-M14
- Rotary robot arm (heavy-lift)
- Auto loading/unloading system
- X-axis linear-guide force-clamping system
Customer Reviews & Case Studies
★★★★★
Netherlands — Offshore Wind OEM
We produce drive pinions for 5 MW offshore turbine main gearboxes — Φ480 mm M12 helical gears in 42CrMo4. The GBCTN-500 delivers consistent DIN 5 after hobbing, allowing us to skip roughing grinding on 80% of parts. Chip-load stability across 14-ton castings is remarkable. After 24 months and 6000+ parts, spindle runout has not measurably degraded.
— Principal Manufacturing Engineer, offshore wind drivetrain division
★★★★★
Brazil — Cement Plant Drive Manufacturer
Our core product is M10-M14 pinions for cement kiln drives. The GBCTN-500's 2000 Nm table torque handles deep M14 cuts in normalised 34CrNiMo6 without table stall — something our previous machine failed on repeatedly at M12. Full-batch cycle time dropped 29%.
— VP Manufacturing, cement plant equipment division
★★★★☆
Singapore — Marine Engineering Group
We repair and reverse-engineer marine thruster reduction gears for vessels drydocked in our yard. The GBCTN-500 covers our entire range from M8 to M14 in a single machine. FAT documentation and FANUC backup discs simplified our classification-society process qualification. Setup support from GBC was thorough and professional.
— Technical Director, marine engineering and repair yard
Frequently Asked Questions
Q1: Why is the GBCTN-500 table speed lower than smaller models?
The Φ450 mm table's Max.100 rpm limitation reflects the torque-to-inertia balance needed for stable synchronisation with the hob spindle during M14 cutting. At M14 module, the optimal cutting speed results in low workpiece RPM anyway (often 5-20 rpm during heavy cuts), so the 100 rpm ceiling does not constrain production.
Q2: Can the GBCTN-500 hob worm gears?
Yes. The machine's +35/-45 deg A-axis helix range and electronic gearbox synchronisation support single- and multi-start worm hobbing. Large-diameter worms up to Φ500 mm can be produced using the full Z-axis travel (365 mm, 400-765 mm).
Q3: How should I specify hobs for M14 module cutting on this machine?
For M14, GBC recommends Φ180-200 mm OD high-speed steel PM hobs with 3-4 gashes and a TiAlN or TiCN coating, matched to the BT#50 arbor. Solid-carbide hobs can be considered for dry cutting of aluminium bronze or cast iron. GBC can supply matched tooling packages with each machine order.
Q4: What are the lifting and installation requirements for the GBCTN-500?
The GBCTN-500 ships at 14.0 ton gross weight, requiring a 20-ton overhead crane or heavy-load trailer with hydraulic gantry. The foundation requires a minimum 600 mm deep reinforced concrete pad with six precision levelling bolts. Floor space including chip conveyor and coolant tank is 4500 x 3700 mm.
Q5: How does GBC support customers in emerging markets operating the GBCTN-500?
GBC provides remote FANUC diagnostic access via secure VPN, a video-based commissioning checklist for local electricians and millwrights, and a dedicated after-sales engineer contact for the first 12 months. Spare spindle bearings, hydraulic seals, and FANUC drive modules are held in GBC's overseas partner depots in Europe, Southeast Asia, and the Middle East.
Elevate Your Heavy Gear Manufacturing with the GBCTN-500
The GBCTN-500 is available for direct B2B procurement, long-term supply agreements, and turnkey heavy-gear production cell projects. Submit your largest and most challenging workpiece drawings — our engineering team will provide a detailed process proposal within 5 working days.
Explore smaller-capacity models in the GBC CNC Hobbing Machine series or visit our homepage for the complete GBC industrial machinery portfolio.
The GBCTN-500 CNC 6 Axis Hobbing Machine is the flagship of the GBC vertical hobbing range, handling workpieces up to Φ500 mm and module M14 with a Φ450 mm direct-drive table generating 2000 Nm torque. It is engineered for heavy-industry gear manufacturers producing wind-turbine main gears, large marine ring gears, and industrial mill-drive components.
