Gauge convertible is a term applies to railway tracks than can be easily converted from one gauge to another. Firstly, the sleepers have to be long enough to take the wider of the gauges, and secondly, the sleepers must be able to take the fittings of both gauges that allow the rails to be fixed securely to those sleepers.

Gauge convertibility is a stepping stone to dual gauge. Sunlight reflects off dual-gauge tracks near Chur, Switzerland Mixed-gauge track and pointwork (1435 mm and 1067 mm) at Odawara in Japan Dual-gauge or mixed-gauge railway is a special configuration of railway track, allowing trains of different gauges to use the same alignment. ...

In cases where the differences between the guages are small, such as 1000mm/1067mm and 1435mm/1600mm, dual gauge with a third rail may not be practicable, in which case gauge convertibility is the next best thing.

Nigerian railways have installed gauge convertible sleepers on the new branch line from Port Harcourt to Onne. Location of Port Harcourt in Nigeria Port Harcourt is a city located in the Niger Delta in Nigeria. ...

Sleeper types

Timber sleepers, provided that they are long enough, are always gauge convertible, since additional holes for the dogspikes can always be drilled.

Concrete sleepers cannot be converted as an afterthought, but must have the future fittings cast in place at the manufacturing stage.

Steel sleepers should have the extra fitting incorporated at the initial manufacturing stage, thouugh it might be possible to drill or weld the fitted sleeper after installation albeit with some difficulty.

Examples

• Melbourne to Adelaide - convertible sleepers installled in 1990 to facilitate quick conversion in 1991.
• Adelaide - convertible sleepers installed should gauge conversion be needed in future.
• Port Harcourt - Onne - convertible sleepers installed since gauge conversion not imminent.
• The Mt Gambier line in South Australia was fitted with some 3-gauge steel sleepers when it was "temporarily" converted from 1067mm to 1600mm in the 1950s, pending later conversion to 1435mm.
• Spain is building its High Speed lines to 1435mm gauge, even though the existing system is 1676mm; new cutoff lines are being built with gauge convertible sleepers for easy conversion to standard gauge when required.
• Central Asia - while China and Europe are connected by rail, and while both are mainly 1435mm, the intervening Central Asia Railways are 1524mm gauge. Intervening lines are gradually been made gauge convertible to facilitate and eventual linkage of the Chinese and European standard gauge system.