CONICAL springs which have been developed by Freudenberg Schwab to integrate the functions of steel coil springs and flexible axle bearings into a single component will to be demonstrated at the Railtex exhibition in London this month (p93). The design offers a large transverse to longitudinal stiffness ratio, with a vertical stiffness of 550?N/mm, transverse stiffness of 6 000?N/mm and longitudinal stiffness of 10 000?N/mm producing a shock absorber element with a ratio of 1:11:18, twice the values previously achieved by standard springs. Further advantages are low structure-borne noise transmission and freely-variable progressive load/deflection characteristics over a wide range.The extremely variable ratios of vertical to transverse stiffness offers rolling stock designers improved kinematic, acoustic and suspension performance at high speeds, while the integrated component offers significantly reduced design, procurement and installation costs. Modern elastomers provide improved creep characteristics, with the manufacturer quoting an absolute creep of 9?mm in six years, and resulting opportunities to cut maintenance costs.Based in Henningsdorf, near Berlin, Freudenberg Schwab also supplies other rubber-metal parts for primary and secondary suspensions and other rolling stock applications, including bushes, buffers, spherical and cylindrical bearings.n