Bulgarian heavy industries, mostly machine building, chemicals, and electronics, were concentrated in relatively few production centers. Important machine tool plants were the Bolshevik Tool Plant at Gabrovo, the Nikola Vaptsarov Combine at Pleven, and the Radomir Heavy Equipment Plant in southwest Bulgaria. The Electronic Materials Processing and Equipment Scientific-Production Combine was a combined scientific and industrial center at Sofia. Electronic instrument production centers were located at the Plovdiv Power Electronics Plant, the Shabla Electromechanical Plant on the northeast coast, the Stara Zagora Industrial Robot Plant, the Pravets Instrument Plant in the southwest, and the Petkov Instrument Plant at Turgovishte. Major chemical and petrochemical producers were the Industrial Petrochemical Plant at Pleven (specializing in vehicle lubricants and oils), the Burgas Petrochemical Combine (plastics), the Vratsa Industrial Chemical Combine (chemical fertilizers), and four chemical plants at Dimitrovgrad (see fig. 10). Bulgaria also built large numbers of ships, many for Soviet customers, at its Ruse and Varna shipyards on the Black Sea. The Shumen Vehicle Plant assembled LIAZ-Madara heavy trucks in a three-way arrangement with the Liberac Auto Plant of Czechoslovakia and the Soviet Union.

Data as of June 1992