The CT450L from Fritz Studer AG and the Kronos S 250 from Schaudt Mikrosa GmbH, available in North America through United Grinding Technologies, offer two distinct benefits for grinding operations. As an entry-level model machine, the CT450L delivers low cost per-part production for general internal grinding applications, grinding spring collets, or machining brittle materials. On the other hand, the Kronos S 250 is flexible and provides multifunctional capabilities.
Shops can undertake simple grinding tasks such as bores, surfaces and tapers, as well as complex contours on the CT450L. A special machine concept of fixed grinding spindles and movable workhead on a generously dimensioned cross-slide make set ups, part loading and measuring easy on the machine, which also includes a linear spindle arrangement and uses one or two belt spindles with speeds of 28,000 to 60,000 rpm.
The Kronos S 250 performs infeed and throughfeed grinding using both conventional and CBN grinding wheels with a diameter range of 1.5 mm to 35 mm and an infeed width to 245 mm. With an enlarged maximum allowable wheel diameter of 400 to 450 mm, the machine increases wheel life by 30 percent.
Cross-slide units are located on the grinding wheel and regulating wheel sides, and combined with dynamic digital drives and high-precision ballscrew unit, the machine operates from only four CNC axes, yet provides the same functionality and flexibility of a six axis machine.
High-performance grinding wheel spindles and maintenance-free hybrid roller bearings on the Kronos S 250 make it possible for the machine to use CBN wheels at peripheral speeds to 150 m/s. An innovative dressing system for the grinding and regulating wheels works by using four CNC axes in the center on the workpiece level.
For grinding wheel dressing, there are optional stationary or rotating dressers available, which can quickly be changed. The stationary grinding gap allows for the use of low-cost automation equipment without any follow-up axis.
