tubes and method of manufacturing tubes from alloyed steel adapted to be welded for underwater hydrocarbon pipelines having high ductility at low temperatures . a low carbon alloyed steel containing less than 0 . 08 % carbon and with at the most 0 . 30 % silicon , also containing manganese and a metal generating special carbides such as molybdenum , niobium , vanadium and like - acting substances , is cast in a centrifugal casting mould after which the centrifugally cast tube is subjected to controlled cooling and a thermal treatment . tubes so constructed may be used for drilling tubes , tubes for underwater pipelines and tubes for the construction of drilling platforms at sea in cold regions and applications requiring high ductility at low temperature .