Sandvik Steel has developed a production method for internally, longitudinally finned, cold-finished tubes for use as pyrolysis tubing in the demanding environment of ethylene furnaces.
With supply approvals having been obtained from key contractors, Sandvik has become an approved industry supplier. As a result, a major order has been obtained from Russiaâs largest oil company, Luk Oil Europe Holding Ltd, for the supply of furnace radiant tubes for four furnaces at the Luk Oil ethylene plant in Burgas, Bulgaria. A previous order had been delivered last year to Borealis AB, Swedenâs only ethylene producer. In the ethylene process, steam and hydrocarbon are mixed together and heated, resulting in a tube metal temperature of between 900° and 1150° C and extremely aggressive and corrosive conditions. In order to extend the life of tubes in such an environment, Sandvik produces the required 2â?-3â? (50mm-76mm) outside diameter finned tubes in a modified high temperature steel grade Sandvik 353MA (UNS S35315) – an austenitic, chromium-nickel steel alloyed with nitrogen and rare earth metals. The chemical composition of Sandvik 353MA is optimised to provide a material with excellent carburisation and oxidation resistance. It has a high creep strength and maintains a very good structural stability in the temperature range required for service in ethylene furnaces.
Sandvik 353MA is manufactured under licence from AvestaPolarit.
