• GI-20NⅡ
  • GI-20NⅡ
Stable, high-accuracy grinding
Traditional Okuma 5-sided hydrostatic guideway
  • Both cross-slide and table always raise with oil to achieve high follow-up accuracy.
  • Higher rigidity with support on 5 sides from upper and lower portions of slide.
  • Distance between two guideways is wide, and vibration absorption characteristics are improved simultaneously with high speed and high rigidity.
  • With closed structure holds top and bottom solidly in place, accuracy and guideway durability are improved.
  • The best machines for die/mold contour grinding.
Guideway (5 points of contact)
Thermo-Friendly Concept
The Thermo-Friendly Concept delivers high machining accuracy with a unique machine construction design and thermal deformation control technology. The Thermo-Friendly Concept releases you from bothersome dimension compensation and warming-up, and provides outstanding dimensional stability even during long-time operation or changes in the plant temperature environment.
  • Achieves high thermal stability not only during room temperature change, but also at machine startup and restarts.
  • Thanks to stabilized thermal deformation, warming-up time is shortened and the burden of dimensional correction during machining restart is reduced.

※ This (TFC) is not available with 4WS and belt-driven grinding wheel specs.

Machining dimensional change over time: ø6 μm(Per 8℃ room temp change. Actual data with TAS-C.)

※ The above are actual examples. Your results may vary due to differences in specifications, tooling and cutting conditions.

Greater machining efficiency
Benefits of numerically controlled oscillating traverse
  • Higher removal rates, lower cycle times
  • Improved surface roughness compared to conventional traverse grinding
  • Ideal for long workpieces
Benefits of numerically controlled oscillating traverse
  • 2-wheel spindle (2WS)
    2-wheel spindle (2WS)

    Expanded range of uses for grinding wheel, including cylindrical and internal grinding, roughing, and finishing.

    2-wheel spindle (2WS) Grinding wheel spindle
  • 4-wheel spindle (4WS)
    4-wheel spindle (4WS)

    Up to 4 high frequency grinding wheel spindle sets can be mounted, enabling greater diversity of integrated grinding operations than with 2WS, and more efficient grinding.

    Grinding wheel spindle

Machine Specifications

Item Unit SBK SHK 2WS 4WS
Capacity Grinding bore range mm (in) ø5 to 200*1 (ø0.2 to 7.87)
ø5 to 300*2 (ø0.2 to 11.81)
ø5 to 300
(ø0.2 to 11.81)
ø5 to 200
(ø0.2 to 7.87)
OD grinding range mm (in) ø200*1 (ø7.87)
ø100*2 (ø3.9)
ø200*1 (ø7.87)
ø100*2 (ø3.9)
ø200 (ø7.87)
Max grinding lengh mm (in) 200 (7.87)
400*3 (15.75)
200 (7.87)
400*3 (15.75)
130 (5.12)
Swing within chuck cover mm (in) ø400 (15.75)
Spindle support capacity
(workpiece mass × distance)
kg×mm (Ib×in) 150×200 (330 × 7.87)
Work spindle Spindle nose dia mm (in) ø100 (ø3.94)
Spindle bore mm (in) ø70 (ø2.76)
Spindle speed min-1 100 to 750
Spindle speed settings (C-axis) Infinitely variable (by NC programming)
Workhead Swivel angle deg 10
X-axis travel mm (in) 200 (–50 to 150 (–1.97 to 5.91))
Travel / pulse-handle revolution mm (in) ø0.1, ø1.0, ø5.0 (ø0.004, ø0.04, ø0.20)
Travel / pulse-handle gradation mm (in) ø0.001, ø0.01, ø0.05 (ø0.00004, ø0.0004, ø0.002)
Auto-infeed rate mm/min (ipm) ø0.0012 to ø6,000 (ø0.00005 to ø236.22)
Positioning rate mm/min (ipm) ø20,000 (787.40)
Z-axis travel mm (in) 500 (19.69)
Travel / pulse-handle revolution mm (in) 0.1, 1.0, 5.0 (0.004, 0.04, 0.20)
Travel / pulse-handle graduation mm (in) 0.001, 0.01, 0.05 (0.00004, 0.0004, 0.002)
Auto-infeed rate mm/min (ipm) 0.0006 to 6,000 (0.00002 to 236.22)
Table oscillation travel mm (in) Max 10 (0.39) (via parameters)
Table oscillation number osc/min 335, 293, 260, 234, 213, 195, 180, 167, 156, 146 (via parameters)
Positioning rate mm/min (ipm) 20,000 (787.40)
Wheelhead Swivel angle deg 5
Travel (left-right) mm (in) 350 (13.78)
Wheel dresser Swivel type Swivel type (for 4WS)
Motors Wheel spindle drive kW (hp) 5.5 to 7.5 (7.3 to 10) 3.7 to 7.5 (4.9 to 10)
Workhead spindle drive kW (hp) 3.5 (4.76) (brushless motor)
Coolant pump kW-P (hp-p) 0.25 (0.34)-2
Hydraulic oil / lube pump kW-P (hp-p) 0.75 (1)-4
Cross-slide (XA-axis) kW (hp) 2.9 (3.94) (brushless motor)
Table (ZA-axis) kW (hp) 2.8 (3.81) (brushless motor)
Tank capacity Hydraulic & lube oil tank L (gal) 40 (10.6)
Coolant tank L (gal) 180 (47.6)
Machine height mm (in) 2,010 (79.13) 2,110 (83.07)
Floor space mm×mm (in) 2,500 × 2,955
(98.43 to 116.34)
(98.07 to 116.34)
(117.32 to 129.92)
Net weight kg (Ib) 4,500 (9,900)
4,800*3 (10,560)
4,800 (10,560)
5,100*3 (11,220)
5,000 (11,000)

*1: With grinding wheel diameter ø100

*2: With wheelhead 50 mm offset specifications (Optional)

*3: With center rest specifications (Optional)