Hardinge Kellenberger VM30
Key Specifications
X Travel
Z Travel
Max Workpiece ⌀
max workpiece length
max workpiece weight
chuck load
Overview
The Hardinge Kellenberger VM30 is a compact CNC internal grinding machine designed for precision bore grinding of small-to-medium components. With a maximum workpiece diameter of 150 mm and maximum length of 150 mm, the VM30 is purpose-built for high-precision ID grinding of components such as bearing races, gear bores, hydraulic valve bodies, and precision bushings where bore geometry and surface finish are critical quality parameters.
The VM30 features one or two high-frequency internal grinding spindles with speeds ranging from 3,000 to 120,000 RPM and up to 7.5 kW power. The 120,000 RPM maximum speed enables the use of small-diameter grinding wheels at optimal surface speeds, which is essential for grinding small bores where wheel diameter is constrained by bore size. The spindle holder bore accommodates wheels up to 100 mm diameter.
Axis travels include 300 mm on Z and 325 mm on X, with feed rates of 20,000 mm/min and 18,000 mm/min respectively. Scale resolution of 0.1 microns on both axes provides the positioning precision required for bore grinding to sub-micron tolerances. Roundness accuracy reaches 0.4 microns standard and 0.2 microns with fly grinding techniques. The machine supports workpieces up to 50 kg with 100 Nm maximum chuck load.
The VM30 runs on a Fanuc 0i-F Plus CNC control with a 19-inch touchscreen and Kellenberger's BLUE Solution grinding software. The compact 1.8 x 1.8 m footprint and 3,000 kg weight make it suitable for precision grinding cells where floor space is limited. New VM30 machines price between $250,000 and $380,000. The machine competes with the Studer S121, Voumard 150, and Toyoda GI20M in the precision internal grinding segment. Specs sourced from Kellenberger published data.
Full Specifications
| Parameter | Value |
|---|---|
| Max Workpiece Diameter | 150 mm (5.9 in) |
| Max Workpiece Length | 150 mm (5.9 in) |
| Max Workpiece Weight | 50 kg (110 lb) |
| Chuck Load | 100 Nm |
| Z-Axis Travel | 300 mm at 20,000 mm/min |
| X-Axis Travel | 325 mm at 18,000 mm/min |
| Axis Resolution | 0.1 um |
| Roundness Accuracy | 0.4 / 0.2 um (fly grinding) |
| Internal Spindle Speed | 3,000 - 120,000 RPM |
| Internal Spindle Power | 7.5 kW max |
| Spindle Bore | 100 mm |
| Number Of Spindles | 1 or 2 (high-frequency) |
| CNC Control | Fanuc 0i-F Plus |
| Machine Weight | 3,000 kg (6,614 lb) |
| Floor Space Required | 1.8 x 1.8 m |
Specifications sourced from kellenberger.com — verified 2026-03-28
Strengths & Limitations
Strengths
- 120,000 RPM maximum spindle speed enables optimal surface speeds even with small-diameter grinding wheels for tight bore grinding
- 0.2 micron roundness accuracy in fly grinding meets the most demanding bore geometry specifications
- Dual-spindle option allows roughing and finishing with different spindles without manual changeover, reducing cycle time
- Compact 1.8 x 1.8 m footprint is the smallest in the Kellenberger lineup, fitting easily into precision grinding cells
- 0.1 micron axis resolution provides the fine positioning control essential for bore grinding to sub-micron tolerances
- BLUE Solution software simplifies bore grinding cycle programming with guided setup for common ID grinding operations
Limitations
- 150 mm maximum workpiece diameter and length limit the VM30 to small-to-medium components only
- No external grinding capability means a second machine is needed for OD grinding operations
- 50 kg workpiece weight limit is relatively low; heavier chucked parts require the VM1000 platform
- 120,000 RPM spindles require specialized maintenance and balanced grinding wheels to prevent vibration
Best For
Frequently Asked Questions
01
New Kellenberger VM30 machines price between $250,000 and $380,000 depending on configuration. Single-spindle machines with basic dressing start near $250,000. Dual-spindle configurations with diamond dressing, in-process gauging, and automation push prices toward $380,000.
02
Internal grinding wheels are constrained by bore diameter — a 10 mm bore can only accept a very small grinding wheel. At low spindle speeds, small wheels cannot achieve the surface speed needed for efficient grinding. At 120,000 RPM, even a 5 mm wheel achieves 1,885 m/min surface speed, enabling productive grinding in small bores that would be impractical at lower speeds.
03
The VM1000 is a significantly larger and more capable platform with multi-axis B1/B2 rotary axes, larger workpiece capacity (up to 300 mm diameter, 200 kg), external grinding capability, and Fanuc 31i-B control. The VM30 is purpose-built for compact ID grinding with the smallest footprint. Choose the VM30 for dedicated small-bore grinding; choose the VM1000 for combined ID/OD on larger parts.
04
The dual-spindle option allows mounting a roughing spindle and a finishing spindle simultaneously. The machine automatically switches between them during the grinding cycle, using the roughing spindle for fast stock removal and the finishing spindle for final geometry and surface finish. This eliminates manual spindle changes and reduces cycle time by 20-40% on typical production parts.
Videos
Kellenberger
