RailLok™ Adjustable Chair

A type of discontinuous rail support that allows for horizontal and vertical adjustment of the rail. Adjustable chairs are typically made of metallic components, including a fixed base plate; on top of which come shims, whose number and/or thickness can be changed to achieve the desired height. On top of the shims comes an upper plate, which lateral position can sometimes be adjusted as well, for example, by means of slotted holes. Adjustable chairs are generally used when the supporting structure is expected to move, due, for example, to land settlement or sleeper movement in their ballast bed.

The patented Gantrex RailLok™ Adjustable Chair fastening system is specifically designed to accommodate the large movements often associated with shifting rail foundations on the less-than-stable ground, often found at ports and other locations. The GANTREX® RailLok™ ”Adjustable Chair” provides a simple and quick method to bring a runway in compliance with the strictest tolerances, namely ISO 12488-1 Class1. This product compensates for movements of foundations often caused by settling, using a system of shims and elongated holes.