SS Heidberg was a cargo steamship that was built in 1943 in Sweden for a German shipping company. The Allies in 1945 took it for war reparations. She was renamed Empire Convention, and spent about nine months under United Kingdom ownership and management. In 1946 she was transferred to the Soviet Union, who renamed her Эрнст Те́льман – Ernst Thälmann. Her fate is not recorded.
built Heidberg in Helsingborg, and launched her on 6 March 1943. Her registered length was, her beam was, and her depth was . Her tonnages were and .
She had a single screw, driven by a Helsingborgs Varfs three-cylinder triple expansion engine. Steam from its low-pressure cylinder drove an exhaust steam turbine, which powered a compressor. The compressor increased the pressure of steam exhausted from the high-pressure cylinder before it entered the intermediate-pressure cylinder. The pressure also increased the temperature of the steam. This reduced condensation in the intermediate- and low-pressure cylinders, increasing the engine's fuel efficiency and power.
Heidbergs first owner was, who registered her in Hamburg. After the German surrender in 1945, Allied forces seized her at Szczecin.
The UK Ministry of War Transport took her over, renamed her Empire Convention, and registered her in London. Her UK official number 180342 and her call sign was GMFM. The MoWT appointed Ellerman's Wilson Line to manage her.
Empire Convention was one of a number of ships that the UK transferred to the Soviet Union in February 1946 under the Potsdam Agreement.[1] The Soviet Union renamed her after Ernst Thälmann, who had led the Communist Party of Germany until 1933, and had been executed in Buchenwald concentration camp in 1944.
Ernst Thaelmann became part of the Sakhalin Shipping Company fleet in the Soviet Far East.[2] Lloyd's Register still recorded the ship as extant in 1959. She was deleted from international shipping registers in 1970.