DISCONTINUOUS SUPPORT (ADJUSTABLE)
In 2012, Gantrex developed an adjustable chair solution which meanwhile has been implemented successfully in container terminals in Australia, USA, China and across Europe.
The main challenge in the design of the system was to allow relevelling of the system at any given time during the 20 year design life of the rail track, by use of galvanized shims, without having to untighten the anchor bolts. Since anchor bolts are typically cast in the foundation, either directly in the concrete, using a cement grout, or some kind of anchoring adhesive, they are by definition “anchored in” and therefore nearly impossible to replace. Instead, Gantrex was challenged to design a system where anchor bolts, once torqued, would remain untouched during the design life of the system. And so Gantrex developed its patented adjustable chair with a 3-bolt design, where the 3 functions of the bolts — clip assembly, plate assembly and anchoring — have been properly separated.
The second challenge was to answer to the requirement for 100mm of vertical adjustment whilst keeping the maximum stability of the rail fastening system under extreme horizontal loads. Indeed, the more the system was being relevelled, and the higher the shimmed solution became, the more critical became the stability of the “tower” in resisting horizontal forces. Once again, by seperating the clip bolts and the plate assembly bolts using a 3-bolt design, in combination with the patented RailLok® clip system, Gantrex’ system has been able to resist in the most strenuous of circumstances.