Plastic bearings are used for the articulated joint on a sit-on ski, for a seat that is fixed to a pair of skis, which can be used by cross-country skiers with paraplegia. To improve their skiing capabilities, a three-dimensional mechanism was developed that adjusts the seat height, moves one ski differentially, turns the ski and inclines the seat simply by applying force through the ski poles. The hinge points were exposed to difficult conditions: vibration, random forces, sudden impact and cold, wet snow. The mechanism consists of two parallelograms, which are joined together by a four-bar connecting piece. The legs were fastened to the seat with linear plain bearings. The three-dimensional mechanism has 23 pins of which 9 consist of iglidur® linear plain bearings made of plastic. The others uses igubal® ball rod end bearings. The plastic bearings were also used for the quick-release fasteners, the devices with which the skis are fastened to the seat.
"The properties of their light weight and self-lubrication, as well as the possibility to be used in cold, wet surroundings, made iglidur® and igubal® the ideal choice for this category of outdoor sports equipment."