Cherepanovs, Yefim Alekseyevich (1774-1842) and Miron Yefimovich (1803-1849), Russian inventors and industrial engineers, father and son. They were serfs of the Demidovs - a famous family of factory owners. In 1810s, Yefim built a progressive machine-building plant, equipped with a full range of innovative metal-cutting lathes (such as screw_cutters, gear_cutting serrating machines and others). From 1822 until his death, Yefim had been chief mechanic of all the factories in the town of Nizhny Tagil. His son Miron was his apprentice and in 1819 was appointed his deputy and eventually replaced his father after his death.

Cherepanovs significally improved the machinery that had been used in blast_furnace and gold_mining industries, iron and copper works, sawmills and flourmills. However, the most interesting aspect of the Cherepanovs' work were steam engines which they stubbornly tried to introduce into industrial production. Since 1820, the Cherepanovs had built about 20 steam engines (ranging from 2 to 60 h.p.). In 1833_34 they built the first Russian steam locomotive, and then in 1835 _ the second one, more powerful. They also built a cast_iron railroad from one of their factories to the copper mine. Despite the successful performance and operation of their locomotives, Cherepanovs' invention found no support outside of the factory and, subsequently, their steam locomotives were replaced with horse traction.