Vertical Machine Turns, Finish Grinds Parts in One Setup
Emag has developed the VLC 100 GT, which combines vertical turning and finish grinding. It is said to reduce cycle times for chucked components as large as 100 mm in diameter.
The machine uses the company’s pick-up concept, where the main spindle is used to load and unload workpieces from the integrated conveyor belt or shuttle. Users can equip the machining area with a variety of turning and grinding modules.
The first step is to pre- or complete-machine component surfaces that can be hard turned. Then, without changing the setup, the machine finish grinds areas that require high-precision geometries. This process has two advantages: the turning process is faster than grinding flat surfaces, and using the grinding tools for only finish grinding operations reduces wear and tear, the company says. Because the workpiece is machined in a single setup, the process is more efficient than when carried out on two machines. It also reduces costs and ensures quality.
The machine can be used as a conventional vertical grinding center, equipped with two grinding spindles for external and internal grinding, or for combination machining, with an additional block toolholder for hard turning operations. It can be equipped with corundum or CBN grinding technology, and users can dress vitrified-bonded CBN grinding wheels using a rotating diamond roll. A structure-borne sound system serves as GAP-control between the dressing roll and grinding wheel. An adaptive process control system promotes shorter cycle times.
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An integrated measuring probe, located between the machining area and pick-up station for protection from debris, enables measuring to take place in the same setup either before or after machining to save clamping time. The probe can also take intermediate measurements.
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