Ethylene Plant Steam Cracker Coil Systems 1.Standard:ASME,ANSI,ASTM,DIN,GB 2.Material: ... may vary from 30 to 50m.Before the 1960s,cracking tubes were rranged in horizontal rows in a radiant chamber, ... 20,000 mta,metric tonnes per annum).Modern designs use tubes arranged in vertical rows,providing superior mechanical performance and higher ... ,mta20,000-250,000 Ethylene Plant Steam Cracker Coil Systems