Insulated joints

The glued insulated joint is a special kind of fishplate which serve for the firm joining the ends of two adjacent pieces of rails in a special insulated way, so that a metal contact conducting electricity neither through the ends of the rails nor through the fishplate joint may be generated. Insulated joints are used at signalling systems, at switch and turnout sections and at any other parts of the rail track where for any purpose the insulation of the rails from electric conductivity is required.

In case of insulated joints besides fastening of the fishplates joining the rails by high strength bolts with nuts, the physically joining surfaces are in addition glued as well for an increased strength of the joint. Just like regular fishplates, the glued insulated rail joints serve the continuity of the rail track for a smooth movement of rolling stock over the rails.

Nowadays also insulated joints made of polymer composite materials and frequently with fiberglass reinforcement and by synthetic resin glue are commonly applied.