chainflex® CF98 control cables are used in the pneumatically operated passenger doors on subway trains. 50 vehicles with four carriages each have a total of 800 doors. The average number of opening/closing operations per year and per door is around 50,000. Initial problems developed with a copper-based cable after just 6 months, which prompted the search for an alternative cable.
The chainflex® CF98 control cable is an alloyed cable, which is softer in its molecular structure and therefore not inclined to become brittle or break when flexed. As a result, service life has been increased: the control cable has accomplished 450,000 door cycles without any interruption or error message during testing. Since each train was retrofitted with CF98, no failures have been recorded. Despite this high-stress application, the cables can expect a minimum service life of 20 years.