Steel Sleepers (aka NR/SP/TRK/021)
|Publication Date:||1 February 2003|
This specification details the information Railtrack requires in order to consider the type approval of steel sleepers proposed for installation in its infrastructure, and the criteria that will be applied.
Requirements are defined for geometry, durability, lateral resistance, rail fastening performance, electrical resistance and branding. Requirements are also set out for the control of the production process so that the consistency of the sleeper's performance is assured.
Sleepers for use with both 56E1 and 60E1 rails are covered but this specification does not cover sleepers for use in track with fishplated joints, other than insulated rail joints, nor for use where the cant deficiency exceeds 150mm.
Two categories of sleeper are included, distinguished by their cyclic loading resistance. The first is suitable for axle loads up to 25.5 tonnes and curve radii down to 400m; the second is suitable for 30 tonne axle loads and should also be used where the track radius is less than 400m but not less than 250m.
To ensure the serviceability of steel sleepers installed in Railtrack's permanent way.