The S121 from STUDER is a universal internal cylindrical grinding machine for medium-sized workpieces in individual and small batch production. Equipped with the advanced technology of its sister machines S131, S141 and S151, this series model has been limited to the essen-tial equipment. A striking example is the spindle turret, which swivels through 180° to a stop and is equipped with two grinding spindles. Alternatively a fixed spindle is possible. With the S121 STUDER has thus created a tailor-made machine for internal, surface and external grinding of chuck components, which offers exceptional value for money.

While a T-slide arrangement or the use of maximum two tools guarantees the attractive price, the manufac-turer has made no compromises in terms of the advanced technologies used. This is evident in the StuderGuide® guideway system for the X- and Z-axis, which guarantees high geomet-rical traversing and guidance accuracy through the entire speed range, together with high load capacity and cushioning levels. At the same time the combination of StuderGuide®, line-ar motors and direct measuring systems guarantee exceptional interpolation accuracies.
Although the smallest machine in the universal series in terms of space requirement, larger diameters can be machined on the S121 than on an S131. This makes it a high-performance machine with an impressively compact design and excellent ergonomics. STUDER's offering of high performance in a small footprint with the customized S121 is evident in the swing diameter over the table of 400 mm and the maximum workpiece length of 300 mm, with a maximum grinding length of 175 mm for internal and 100 mm for external diameters. This large range of workpiece dimensions is made possible by optimal arrangement of the ma-chine components.

Tailored to the perfect size
The configuration of the S121 as a tailor-made machine is above all made possible by the fact that the machine can be equipped with a fixed spindle or a spindle turret with two spin-dles. When using a spindle turret, the turret swivels hydraulically through 180° to a stop, and one spindle can be fitted with an external grinding wheel. However, STUDER also imple-ments the "tailor-made" principle through a workhead with manual cylindricity correction, which is adjustably mounted on the workpiece table, and a high-resolution C-axis with direct measuring system, which is ideally suited for form and thread grinding. The machine concept always allows optimum accessibility for the operator, whether for workpiece changeover, dressing or changing the grinding wheel.

The S121 is a universal internal cylindrical grinding machine, which is designed for the pro-duction of high-precision parts. The basis for this precision is the machine bed comprising of Granitan® S103 which, with its excellent cushioning and thermal behavior, ensures outstand-ing surface quality of the ground components. The excellent cushioning behavior also ex-tends the service life of the grinding wheel, which in turn reduces auxiliary times. As the ma-chine bed largely equalizes temporary temperature fluctuations, a high dimensional stability is ensured throughout the machining time. The modules of the S121 are ideally suited to each other and produced with the customary STUDER precision. The large distance be-tween the guideways and the very rigidly constructed slides are further cornerstones for the precision and productivity of this machine. Simple, reliable programming and efficient opera-tion of the S121 is guaranteed by the StuderWIN software. The possibility of fully integrating the in-process gauging and sensor technology for process monitoring as well as contact de-tection and automatic balancing systems in the control enable standardized programming of the different systems. The drive elements are optimally adapted to the control.
The S121 is tailor-made for a large range of internal grinding applications. Numerous appli-cations are in the production of machine tools, drive elements as well as in the aircraft and die industries.