In the second half of the 19th century, when the Pastuhovy merchants from Yaroslavl became the owners, the first restructuring of the company took place (27.05.1850). In 1886 the factory was fully owned by N.P. Pastuchov. During "Pastuhov's Government" a whole group of talented mining engineers were hired to senior positions. Between 1849-1855, the plant was managed by Andrew Hristianovich von Siegel. At this time the construction of the second blast furnace, the puddle welding factory and the construction of the Omutninsk dam began. N.P. Pastuchov was also known for opening a first factory school on his own initiative, building a factory hospital in 1850 and building the first Orthodox church in the name of St. Alexander Nevsky, which was consecrated on 10 June 1853.
In November 1856 the second blast furnace was put into operation and the puddle welding factory began to operate between 1861 and 1862, which gave new impetus to the development of the plant. At that time the puddle method was considered very modern and opened new horizons for the Omutninsk Steelworks (OMP). In the second half of the 19th century (until 1884) the plant produced using the Puddel method, which was also used for rolling sheets and profiles (tire tape, strip, narrow strip, round, etc.). Both blast furnaces were modernised in 1861. In general, the technical equipment of the plant became more complex.