Soviet shipyards started in 1928 with building inland screw steam tugs according to the CIA report called Soviet River Shipbuilding and vessel classification dated around 1955

For the report was the book Osnovy Teorii i Ustroystva Sudov Vnutrennego Planiya of A.P. Strakhov dated 1955 used. An item reported that in 1931 the building was started of inland single screw steam tugs with a horsepower of 140 and 300 ihp. All vessels were welded. Dimensions 22,9 x 5,5 x 2,3 x 1,68 (draft) metres.

Source

The report was published on www.archive.org, document number CIA-RDP80-00809A000700260105-5