SA-213TP347HFG high pressure boiler tube
The ingredient is the same as TP347H, and manufacturing, processing technology different chromium-nickel austenitic stainless steel niobium. Sumitomo TP347H for two problems exist (one TP347H smoke steam side under thermal cycling will produce an oxide layer peeling, and produce at the bend of the obstruction can cause overheating and failure; the second is peeling oxide can be brought the steam turbine, steam turbine to produce serious erosion) has been improved: the use of fine niobium carbide (NbC) dissolution and precipitation mechanism, the introduction of new, higher solution treatment temperature heat treatment process makes grain greatly TP347H refinement. Room temperature, high temperature mechanical properties and TP347H basically the same. As the steel is niobium stabilized austenitic steel, and grain refinement obviously, lasting about 20% higher strength than the predetermined value of the ASME Code, weldability, fatigue performance is much better than the conventional TP347H steel, and has a good between resistance to intergranular corrosion, good organizational stability and more excellent oxidation and release properties, also has good bending performance; its overall performance was significantly better than TP347H. High-temperature corrosion resistance is the best in the 18-8 stainless steel. The steel in recent years have included ASME SA213, named TP347HFG.