Studer Expands Universal Cylindrical Grinder Series

With 100 years of experience, Studer is a well-known brand in precision cylindrical grinding. The company has also carved a reputation for choosing the most distinctive locations to introduce the latest developments in cylindrical grinding technology. This year’s location was no exception—the Hagerbach Test Gallery, an R&D facility for underground mining tunnel construction located in the canton of Graubünden in Switzerland, played host to the Studer Press Event 2019. This event was attended by more than 60 trade journalists from around the globe.

The highlight of the event was the unveiling of the S33 and S31 universal cylindrical grinding machines, which are available in the states from United Grinding. The machines feature an extended range of distances between centers, more than 20 wheelhead configurations, a new B-axis concept and much more. A dark atmosphere, loud music and participants in glowing yellow safety helmets underpinned the underground atmosphere during the unveiling ceremony, which was followed by presentations highlighting the machine series’ new features.

One of the main features of the S31 and S33’s updated versions is the extended range of distances between centers. Both the S31, designed for grinding workpieces in individual, small-batch and high-volume production, and the S33, designed for medium-sized workpieces, are now available with distance between centers of 400 and 1,600 mm, respectively, complementing the existing 650- and 1,000-mm sizes.

Based on the Studer T-slide concept, the machines are available with an extended X-axis stroke. With a stroke of 370 mm (more than 85 mm compared to the current models) it enables additional wheelhead variants. The S33’s new wheelhead can be equipped with a motor spindle for external grinding and a high-frequency spindle for internal grinding in different configurations. Three grinding wheels ensure that the workpiece is machined even more individually and quickly, CSO Sandro Bottazzo explained during the presentation. The new B-axis concept features an automatic 1-degree Hirth coupling with a swivel range of -30 degrees to +210 degrees for as many as two outer diameter (OD) grinding wheels and one inner diameter (ID) grinding spindle for complex tasks. A fixed wheelhead enables swivel positions of 0, 15 and 30 degrees, offering additional flexibility for straight and angular plunge grinding in one machine. The maximum workpiece weight is 150 kg.

The double T-slot of the Z axis for dressing tools in combination with the Studer Quick-Set software for grinding wheel alignment reduces the complexity of setup and machine resetting, Mr. Bottazzo said. Moreover, the Granitan machine base features a new temperature-control concept to improve machine stability and accuracy. An integrated temperature control keeps the machine temperature constant, and a cooling tray flushing keeps the machine clean. A column temperature control is designed to ensure additional thermal stability.

The S31 features StuderGuide guideways with a damping component in the direction of movement. The guideway system uses the advantages of hydrostatic and hydrodynamic guide systems and avoids the slip-stick effect or floating of the slide. As an option, the B axis can be equipped with a direct drive with a resolution of 0.00005 degree. The wheelhead can accommodate as many as three grinding wheels—a combination of external and internal grinding wheels, with a maximum of two external or two internal grinding spindles. For high-precision form grinding with the FANUC 31i-B control system, the S31 features a workhead with a direct measuring system and the StuderFormHSM software program.

Both machines feature a one-piece enclosure designed for easy accessibility of handling systems. According to Studer, both machines can be easily automated for series production thanks to the standardized loader interface (the machines can be loaded by a robot from the front or by a gantry robot from top). The standard control is a FANUC 0i-TF with the user-friendly StuderWIN programming software. The machines are compatible with OPC UA and MTConnect.