Complex sentence: The biggest company currently operating in Taganrog is Taganrog Metallurgical Plant (publicly traded company Tagmet) which manufacturs steel, steel pipe for oil and gas industry and consumer goods.
Split into simpler sentences: The biggest company currently operating in Taganrog is Taganrog Metallurgical Plant, (publicly traded company Tagmet). The plant manufactures steel, steel pipe for oil and gas industry and consumer goods.