Due to constant movement and abrasion of the tracks in the turning station of Line 7 of the Stockholm Tramway during operation, they had to be replaced within a very short time. In addition, the wooden sleepers that had already been installed were coated with the necessary environmentally harmful impregnating agents, which should now be replaced with a more environmentally friendly alternative: Composite Sleepers made from 100% recycled plastic. One challenge was that the track was located in a tight curve, which meant that the track and the sleepers were exposed to large lateral forces. In addition, the sleepers were to be supplied together with the track as a track yoke.
