Precision boring mill KG

Precision in perfection

The planer-type precision boring mill KG is the solution for all those who manufacture and machine their workpieces to the highest quality standards. Based on the reliable planer-type K-Series, it unites the advantages of a classic boring mill with those of a precision boring machine: flexibility combined with much higher precision and investment costs which are well below those of a jig boring machine.

Complex, prismatic workpieces with dimensions of more than 2,500 x 2,000 x 1,500 mm and a weight of up to and more than 6 t are machined with extremely high precision. KG is the first machine tool to close the market gap between a conventional boring mill and a jig boring machine.

Boring spindle diameters available:

  • 110, 125 mm (or larger on request)

Your advantages at a glance

The precision boring mill KG sets benchmarks in terms of geometrical precision, positioning accuracy and thermal stability, which is achieved by intelligent temperature compensation. The machine has been specifically developed for the high demands of those industries that depend on the highest precision and maximum performance, such as gear manufacturing, classic mechanical engineering and manufacturing of precision parts.

Highly precise and flexible

The boring mill offers unique flexibility. Contours deep within the workpiece can be machined with high precision. Easy access to the work area allows for manual process monitoring. In addition, the machine has an extremely high torque. Flexibility and highly precise machining results – KG fulfills the highest demands.

The foundation of outstanding precision

The concept for the new precision boring mill is based on the K-Series. There is no cross slide: the separate beds of the X and Z-axes can be perfectly aligned to guarantee an even distribution of load. The three guideways of the Z-axis minimize the column tilt. The extraordinary stiffness of the entire machine is due to strong ribbing. All structural components are manufactured with high precision; the guideways are hand-scraped. The table is extremely stable, its surface precision-ground. In addition, the machine is equipped with highly precise measuring devices.

To avoid heat development, the main spindle is equipped with a ceramic hybrid bearing. A cooling unit with heating and cooling device, temperature-controlled gear oil cooling and water-cooled main spindle and Y-axis drive ensure the highest thermal stability.


For production facilities without air conditioning, the companies of the HerkulesGroup offer optional equipment:

  • Air-conditioned operating platform including space to temper measuring devices
  • Air-conditioned enclosure of the entire machine, including additional storage space for workpieces

Many additional options are available on demand, such as:

  • Precision interface for adding equipment
  • Comprehensive extension of control functions
  • Automatic tool changer

Positioning accuracy

Positioning accuracy according to VDI / DGQ 3441*

Positioning uncertainty Plinear µm < 8
Average pos. tolerance spread Psmaxlinear µm < 6
Reversal error Umaxlinear µm < 3
Positioning deviation Palinear µm < 4
Positioning uncertainty Prot arcsec < 8
Average pos. tolerance spread Psmaxrot arcsec < 5
Reversal error Umaxrot arcsec < 4
Positioning deviation Parot arcsec < 6

* Tolerances valid in air-conditioned environment only


Technical data – Example KG 110/125

Boring spindle    
Diameter mm 110/125
Main drive (S1) kW 31
Torque, max. Nm 1,870
Speed, max. min-1 4,000 / 3,700
X-axis mm 2,000
Y-axis mm 1,600
Z-axis mm 1,500
W-axis mm 550
Table size mm 1,000 x 1,250
Table load t 6
Tool magazine Pockets 40
Tool taper   HSK A100
  • K  Planer type
  • G  High-precision boring mill

Product film

Any further questions?

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