Schaeffler expands portfolio for machine tools

In the machine tool industry, automation, digitalization, and sustainability are among the driving forces that are significantly influencing machine architecture and key components such as spindles, linear axes, and rotary tables. Schaeffler is responding to these important industry trends and developing innovative bearing and drive solutions that will be presented at EMO 2025.

For axes outside the machining area, as well as for workpiece and tool handling, manufacturers require particularly low-maintenance and durable rotary axis bearings and linear guides. In addition, a new optimum balance between function and cost-effectiveness must be found so that the return on investment for the automation solution can be achieved quickly. The new four-row profile rail guides of the KLLT series in an X arrangement meet precisely these requirements. They expand the portfolio of Schaeffler linear guides specifically for the requirements in the periphery of production machines. The KLLT profile rail guides are particularly characterized by their ability to adapt better to sub-assemblies with minor dimensional errors without generating significant constraint forces, thus opening up new applications for Schaeffler.

New rotary axis bearings for automation

For rotary axes outside the machining area, Schaeffler engineers have developed the new YRTA series (A = automation) based on their proven YRTC rotary axis bearing series. With modified manufacturing processes and a new needle cage, these double-acting axial roller radial needle roller bearings ideally meet requirements such as high tilt rigidity, long service life, and low maintenance.

Sustainability as a development criterion

In driven rotary tables, especially those not used for simultaneous machining, there is a trend toward gearmotors. To reduce the considerable design effort required for rotary axes with gearboxes, the installation space, complexity, and assembly time, Schaeffler developers have come up with an innovative solution: The YRTC and YRTA rotary axis bearings can be ordered with spur gear teeth on the outer diameter (YRTCG, YRTAG). The gear teeth replace the customer's spur gear. Depending on the required torque, the inner ring is designed in the appropriate width and with straight or helical teeth. This solution is ideal for driving milling tables and swivel axes of milling bridges and milling heads or automation axes. The integration of the AMOSIN angle measuring system into the bearing is not affected and the angle measuring system is still available for these bearings.

New roller screw drives

With the acquisition of Ewellix and the harmonization of the product range, additional sizes of ground roller screw drives RGT have now been added to the Schaeffler Linear Motion portfolio. Customers can now choose from sizes ranging from 8 to 240 mm with a load rating of up to 4,000 kN.

In the machine tool industry, these roller screw drives are used, for example, in feed axes of thread rolling machines, in drill/mill heads, and as drives for broaching machines—in other words, wherever high forces, precise positioning, and monitoring of the force-displacement curve are required. For the important feed axis market, Schaeffler offers a wide range of KGT ball screw drives and, for special applications with small overall pitches of less than 1 mm, the PWG planetary roller screw drive.

Problem solvers for short-stroke applications

If thread drive bearings on feed spindles are permanently exposed to small swivel angles, there is a risk that the lubricant will be forced out of the rolling contact and damage the rolling bearing due to insufficient lubrication (“false brinelling”). Schaeffler offers a simple, practical, and efficient solution for these applications: the double-row angular contact ball bearings of the ZKLN and ZKLF series (with flange mounting) and the three-row DKFLA variant are equipped with ceramic rolling elements. These designs offer high operational reliability with short strokes and standstill vibrations. The dynamic load carrying capacity and the calculated service life of the bearings remain unchanged. The use of ceramic rolling elements even doubles the grease service life. Downtime and service calls caused by false brinelling can be reliably avoided with these bearings.