Derail
Videos
A derail or derailer is a device used to prevent fouling of a rail track by unauthorized movements of trains or unattended rolling stock. The device works by derailing the equipment as it rolls over or through it.
A derailed train car at a closed siding
A derail device installed on a siding at Glen Haven, Wisconsin, oriented to protect track located off the bottom of the picture
Derail on Nemuro Main Line, JR Hokkaido. It is set so that a train proceeding away from the camera will remain on the track.
Catch points
Videos
Catch points and trap points are types of points which act as railway safety devices. Both work by guiding railway carriages and trucks from a dangerous route onto a separate, safer track. Catch points are used to derail vehicles which are out of control on steep slopes. Trap points are used to protect main railway lines from unauthorised vehicles moving onto them from sidings or branch lines. Either of these track arrangements may lead the vehicles into a sand drag or safety siding, track arrangements which are used to safely stop them after they have left the main tracks.
An insulated track circuit interrupter fitted to trap points
Double trap points protecting the South Wales Main Line at the exit of Stoke Gifford Rail Yard near Bristol Parkway railway station
Double trap points with much longer rails, at Castle Cary railway station