The Russian railways used the letter Б (B) to group express locomotives with a 4-6-0 wheel arrangement, i.e. in Russian notation 2-3-0. Between 1896 and 1903, locomotives with four-cylinder compound engines were manufactured for several railway administrations. The driver's cab was closed off to the rear by the tender. They had cylinder diameters of 370 and 580 mm with a stroke of 650 mm and a coupling wheel diameter of 1,730 mm. In Russian conditions, especially in the harsh winters, maintenance of the four-cylinder engine proved too complicated. They also proved to be too fuel-intensive on long, straight stretches. As a result, many locomotives were converted to simple engines from around 1910 and fitted with superheaters. The new cylinders had a relatively long stroke of 700 mm with a diameter of only 550 mm.
In 1907, the Moscow-Kyiv-Voronesh Railway ordered three locomotives from the Bryansk works, which already equaled the two-cylinder superheated version ex works. From 1909 other railways ordered more examples of this design, so that the number increased to 252, of which 99 were built in Luhansk. The locomotives reached up to 125 km/h in test drives and were certified for 105 km/h. This was later increased to 115 km/h. With the introduction of more modern locomotives, the Б series locomotives were later moved to the eastern, more sparsely populated areas and finally retired in the 1950s.