Grinding Machine Model

Centerless and Between Centers Dual Process Grinding Machine

Studer Mikrosa Kronos Dual Centerless / between Centers Grinder
Kronos Dual  
Kronos L dual -

The KRONOS  Dual is absolutely new! It provides a series of processing benefits thanks to the combination of centreless grinding and grinding between centres.


The technological highlight of the KRONOS Dual is the retention of the workpiece centre in centreless grinding. As the workpiece centre is not lost, nothing is left up to chance any more. Its field of application is to be seen whenever previous or successive work steps require processing from the centres. The KRONOS Dual guarantees shorter processing times by higher stock removal performance, with the combination of grinding between centres and centreless grinding. An economical solution has been found by the machine concept on the tried and tested basis of the KRONOS Dual with all its benefits and features. With the KRONOS Dual innovative development of grinding between centres is achievable.



  • Due to the combination of 2 grinding methods, the workpiece center will remain intact
  • Considerably shorter processing times with high precision in comparison with grinding between centres only, as the workpiece is fully supported and therefore cannot bend.
  • Reduced material handling times
  • Rigid granitan machine bed ensures excellent thermal stability characteristics and superior vibration absorption
  • SIEMENS Sinumerik 840 D control and Simodrive infeed technology
  • Double-end supported grinding wheel and regulating wheel spindle with anti-friction bearings
  • A maximum power of 133 hp allows for powerful chip-removal
  • Semi-automatic grinding wheel changing enables reduction of the grinding wheel changing time to less than 15 minutes
  • Motorized coolant jet adjustment in accordance with the  grinding wheel wear





     Length, max.




Grinding wheel

     D x W x d, max


26" x 26" x 12"

     Peripheral speed, max

208/396 ft/sec

     Spindle drive

80/133 hp

Regulating wheel

     D x W x d, max

     Peripheral speed, max


16" x 26" x 8"

5...700 rpm

     Dressing speed, max

Workcenter support

700 rpm

4 MT


Kronos Dual - Two Processes, One Machine
The Kronos Dual offers an innovative design which permits the combination of two processes - centerless grinding and grinding between centers in a single machine, in a single setup. The results are shorter cycle times, greater through-put and improved part quality due to reduced component handling and the elimination of multiple setups and operations. A reduction in cycle time of 45% is not unusual due to the higher material removal rates of the combined processes compared to grinding between centers alone, which is often limited by between-center grinding workpiece support systems. The Kronos Dual offers an ideal solution for high-volume production of medium- to large-sized precision shaft-type components - workpieces with a common center which becomes the basis for preceding and/or following process operations - such as crankshafts, camshafts, gear shafts and rotor shafts for electric motors.

The dual process
In the combined "2-in-1" process, the workhead and tailstock are installed between the grinding and regulating wheels immediately next to the fixed workrest blade. The workhead is equipped with a fully programmable workpiece driver. The work spindle is axially positioned via a CNC spindle drive. Tailstock support is controlled by a hydraulically activated sleeve, and workhead and tailstock are easily adjusted to appropriate workpiece length and diameter. In operation, the workpiece is first ground between centers concentric to the center, at a material removal rate of 0.05 mm/min to 0.10 mm/min on diameter. After grinding between centers, the workpiece is released, and finish grinding takes place via conventional centerless grinding between the control wheel and workrest blade. This 2-in-1 single setup provides outstanding workpiece stability, resulting in precise part-to-part process repeatability, close tolerances and superior surface finishes.

The Kronos family
The Kronos Dual is an extended, dual process version of the Kronos Dual and incorporates the latest in grinding technology, specifically aimed at dramatically reducing non-productive processing time. The modular machine concept, which provides application-specific machine configuration flexibility, features a rigid Granitan machine base, which guarantees superior vibration dampening and thermal stability. A double-end supported grinding wheel spindle permits surface speeds up to 120 m/sec, and a double-end supported regulating wheel spindle delivers up to 700 RPM for shorter dressing times. A fixed location grinding gap allows for fast cycle times and simple workpiece handling, since no additional compensation axis is required. Semi-automatic, fast grinding wheel change facilitates small-batch manufacturing. The Kronos Dual dual features state-of-the-art Siemens digital control and axis drive components. Machine operation, setup, changeover, dressing and programming of even complex parts are easily accomplished through the innovative step-by-step Mikrosa Symbol Screen Technology. The Siemens Sinumerik 840D control package features application-specific software routines, Windows™ user-interface, integrated on-line help menus and extensive fault/error diagnostics. Remote diagnostics, process control and trouble-shooting via standard telephone line and machine modem link are easily facilitated.




Centerless and Between Centers Dual Process Grinding Machine
Grinder Type: Centerless
Machine Opertaion: CNC
CNC Brand: Siemens 840D
Grinding Length: 24.000 Inches Length: 609.600 mm
OD Grinding Diameter(s) Min: 0.591 , Max: 3.937 Min: 15.000 mm , Max: 100.000 mm
Grinding Wheel Dia.: 25.984 Inches    Width: 25.984 Inches    Bore: 12.000 Inches    Dia.: 660.000 mm    Width: 660.000 mm    Bore: 304.800 mm   
Wheel Head Motor: 80.00 hp  Opt: 133.30 hp Motor: 60.00 kW  Opt:100.00 kW   64 rpm   Angle Adjustment: 0.000°
Regulating Wheel   Speed: 700 rpm
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