The trend towards miniaturisation of components and the simultaneously growing demands for greater precision is unmistakable. It is for these applications that EMAG developed the modular VG 110.
VG 110 - for the vertical precision machining of small chucked components
20.04.2007 - Oliver Hagenlocher
The VG series: for the high-speed machining of small and very small workpieces of 2 to 60 mm diameter
The VG 110 is a production grinder for the machining of large batches of small and very small high-precision workpieces using the following technologies:
- internal cylindrical grinding
- external cylindrical grinding
- out-of-round grinding
- the combination process of hard turning + grinding
The VG 110 provides the user with a choice to either grind the "traditional" way or profit from the advantages offered by the combination of turning + grinding on one machine: Where the process specification permits, sections of the workpiece are soft or hard finish-turned and only finish-ground – in the same setup (and most frequently after having first been pre-turned) – as tolerances demand. This not only improves component quality but also reduces cycle times. It also limits the wear and tear of grinding wheels and, consequently, the number of dressing cycles required. This makes the VG series an attractive proposition for the manufacture of many small, very precise components: (Fig. 6021)
- cup valve pistons and valve bodies for modern fuel injection systems
- rollers and sleeves for monobloc injection pumps and nozzles
- cam rings for fuel injection and power steering pumps, parts for air conditioners in passenger cars, for radial piston pumps and motors
- internal and external polygons on tool shanks or drive shafts
- cylinder liners
A tried and tested machine design coupled with a number of innovations
The machine base in high-grade Mineralit® polymer granite offers maximum thermal stability and has an exceptional damping effect. X- and Z-axis are separate, to ensure that the highest machining quality is maintained on small workpieces. The vertical Z-axis is equipped with a linear drive. This allows the grinding spindle(s) to carry out short, rapid oscillating strokes. The X-axis determines machining accuracy and, as a vertical axis, is completely removed from the machining area. The high-resolution measuring system is only 100 mm away from the machining process. Depending on the application, this allows for tolerances of 0.5 - 1 µm to be held. The work spindle is a frequency-controlled AC motor spindle. Low mass and a high torque rate create particularly outstanding dynamics.
Short travels, high speeds, a high degree of rigidity and an integrated cooling system (for spindle motor, grinding spindles, linear drives and electrical cabinet) help achieve short idle times, high output rates and excellent precision. To compensate for the deflection of the grinding arbour the tooling system can be equipped with a swivelling E-axis.
The modular machine concept allows for the tooling equipment to be adapted to suit individual machining requirements. The following machine variants are available:
- 1 or 2 internal grinding spindles for cylindrical or out-of-round grinding (Fig. 6168)
- 1 internal or 1 external grinding spindle and a turning tool (Fig. 6013a)
The VG 110 offers all cutting-edge grinding technologies
- grinding tools: ceramic or electroplated CBN grinding wheels
- sensory analysis modules: adaptive grinding, touch-recognition, touch-dressing
- dressing technology: dressing spindle for the use of diamond dressing rolls
The control system used is a SINUMERIK 840D. Programming and operation of the machine are made easy by the operator-friendly EMAG software.
Very short loading times
To achieve short cycle times it is more important than ever to keep loading times short also. Loading small workpieces through the work spindle results in very short loading times of around 1.5 s. Workpieces that cannot be loaded through the spindle are taken into the machining area by a shuttle in inserted into the workholding unit by a lift-up loader. Workpiece handling times depend on the workholding unit and can be as low as 4 s.
A forward looking investment
The VG 110 fulfils all the demands made on a modern production grinder:
- high output rates
- exceptional machining quality
- short cycle times
- low component manufacturing costs
- the application of cutting-edge grinding technology
A future-orientated production aid for a multitude of manufacturing tasks
The VG can be used as a stand-alone, but can also be integrated into a fully automatic production line as a self-sufficient link that accommodates turning as well as internal, external and face grinding operations.
Highly flexible in its application, of extremely rigid construction, offering short strokes, high rapid traverse speeds and featuring an integrated cooling system and workpiece loading through the spindle, the machine stands for high output rates, highest precision and the lowest idle times imaginable. And the footprint (5.3 m²) is extraordinarily small too.
The VG 110 – an overview
The modular VG 110 series of machines for the hard turning and grinding of cylindrical components of the following dimensions:
- machining dia. 1 - 60 mm
- free clamping length max 125 mm
- machining length max 60 mm
and used as:
- vertical grinding center
- vertical turning and grinding center