Diesel locomotive Dv12s. In the 21st century series production standard gauge diesel–hydraulic designs include the Voith Gravita, ordered by Deutsche Bahn, and the Vossloh G2000, G1206 and G1700 designs, all manufactured in Germany for freight use. Steam-diesel hybrid locomotives can use steam generated from a boiler or diesel to power a piston engine. The "Cristiani Compressed Steam System" used a diesel engine to power a compressor to drive and recirculate steam produced by a boiler; effectively using steam as the power transmission medium, with the diesel engine being the prime mover The diesel-pneumatic locomotive was of interest in the 1930s because it
TU7 diesel locomotive TU7 diesel locomotive TU7 (ТУ7) - Soviet, later Russian diesel locomotive for gauge – . The TU7 () was developed in 1971-1972 at the Kambarka Engineering Works to replace the aging locomotive classes TU4 () and TU2 (ТУ2). There were 3,361 locomotives constructed, of which several hundred were exported to the countries of the socialist community and affiliated countries. The TU7 - TU7A () was designed to be used on any gauge from to . In 1986 the locomotive design was updated and designated type TU7A (). The D4H and 9 locomotives D4Hr for standard gauge , also known as