Wooden Sleepers

Wooden railway sleepers are not competitive products to concrete sleepers but they are complementing them in particular cases of usage. Wooden sleepers are preferably applied on railway lines located on mountainous territories where the flexibility of sleepers is of major importance. Another field of application of wooden sleepers are those railway branch line sections or sidings, which have been built originally by wooden sleepers, and thus the maintenance and repair of them requires laying new wooden sleepers, as long as the railway line section is not completely refurbished by laying concrete sleepers. Considering the high costs of such comprehensive construction works, most conventional railway line sections laid on ballast bed by wooden sleepers remain unchanged still for quite a while.

Wooden sleepers are protected against harm made to them by fungi and insects by way of impregnation by a special chemical substance called creosote, which is a coal tar pyrolysis derivative with very effective and long-lasting pesticide impact. The impregnation of wooden sleepers is performed in autoclave by vacuum pressure process. The impregnation procedure is determined by the German industry standard DIN 68811:2007-01, while the quality and parameters of creosote oil are determined by the European standard EN 13991:2003. Our sleepers, bearers and beams are impregnated exclusively by creosote type “C” (EN 13991:2003, Table 1).

Since creosote is considered a dangerous substance, therefore in case of railway line sections leading through nature reserve areas and woods are built by wooden sleepers without impregnation, produced of hardwood species, primarily of European oak. This is also one field of application where wooden sleepers are preferably applied. The unimpregnated (raw) wooden sleepers are regulated for quality and performance parameters by the European standard EN 13145:2001+A1:2011.

For the production of running line sleepers mainly beech (Fagus sylvatica) timber is used, while for the production of turnout bearers and bridge beams European oak (Quercus Petraea and Quercus Robur) timber are the raw materials. The standard dimensions are as follows:

Type of wooden sleeper	Standard dimensions
Running line sleepers	160 x 260 x 2600 mm
Turnout bearers	160 x 260 x 2600 – 5200 mm
Bridge beams	240 x 240 (260) x 2500 (2600) mm