Automotive and industrial supplier Schaeffler Group displayed its rotary table bearing range at the world exhibition for machine tools, Exposition Mondiale de La Machine Outil, or EMO 2015 expo, which took place in Milan from October 5 to 10.
Schaeffler’s stand, which also featured angular measuring systems and direct drives, showcased the company’s solutions for precision rotary axes and rotary tables.
The company also included the YRTS axial cylindrical roller bearing, which Schaeffler says leads the technical field in terms of tilting rigidity, while producing extremely high machining accuracy and cutting capacity.
Schaeffler notes that YRTS has a patented raceway geometry that enables it to achieve a previously unattainable low-bearing friction for preloaded roller bearings.
The company explains that a standard rotary table bearing with an inside diameter of 325 mm, for example, would produce a frictional moment of about 90 nm at 100 rpm, whereas the 325 mm YRTS bearing reduces the frictional moment to a mere 10 nm.
This could represent a saving of about 800 W or around R15 000 a year if the machine runs at S1 operation, which is the International Electrotechnical Commission’s designation for continuous duty.
With this in mind, Schaeffler claims that the YRTS sets the benchmark for rotary tables with different machining options, pointing out that its users benefit from the increased production quality owing to lower thermal expansion and reduced operating costs.
The YRTS range has a complementary YRTC series, which is used in larger tables with milling and turning options. The range therefore features a larger bore diameter range of between 580 mm to 1 030 mm. The YRTC series is said to have higher rigidity and considerably reduced power losses compared with conventional axial cylindrical roller bearings.
The company maintained that the larger cutting volumes combined with the reduced frictional losses in continuous operation make an effective contribution to reducing operating costs and improving machine performance.
Schaeffler adds that its flange-mounted axial angular contact ball bearings ZKLDF..B are market leaders in rotary tables with extremely high capabilities in terms of speed.
Limiting speeds for rotary tables can be considerably increased if these bearings are combined with RKI torque motors. If the limiting speeds are not exploited to the full, the user still benefits from the extremely low bearing friction and the associated lower build-up of heat in the structure of the machine, which has a positive influence on the machining accuracy.
Schaeffler Group was established in 2003 when Germany-based industrial components supplier Industrie (INA) united its subsidiaries Lamellan und Kupplungsbau (LUK), acquired in 1999, and Fischers Antiengesellschaft (FAG), acquired in 2001, under one banner.
INA was founded by the Schaeffler brothers in 1946. One of its biggest competitors at the time, FAG, had already been well-established, as it was founded in 1905. Having secured a consistent client base, the brothers decided to branch out in 1965, establishing the automotive systems and components supplier LUK.
Schaefller Group is one of the largest family-owned technology companies worldwide with about 170 locations in 50 countries, including several manufacturing locations, research and development facilities and distribution companies.