308H Stainless Steel TIG wire.
Applications
The 308H consumables are designed to match unstabilised 18Cr-10Ni austenitic stainless steels for elevated temperature strength and oxidation resistance. These steels and the weld metal have carbon content controlled to 0.04-0.08%. Composition limits of the MMA electrodes and FCAW wires are tightened above those of BS/AWS specifications to meet the requirements of Shell and other operators of refinery equipment. Weld metal Cr and Ni are kept low and ferrite is controlled to minimise embrittlement by the sigma phase. Beneficial and detrimental minor elements and residuals are also controlled to optimise high-temperature properties. No bismuth-bearing constituents are allowed in these consumables, to ensure <0.002%Bi as required by API 582. The 308H consumables should also be considered for welding thick (>12mm) stabilised grades 321H or 347H to avoid in-service HAZ cracking and low creep rupture ductility associated with 347 weld metal. Note that some authorities recommend the use of type 16-8-2 types for these steels, including 304H. 308H is widely used in petrochemical and chemical process plants, particularly for the fabrication of cyclones, and transfer lines used to re-circulate the catalyst in catalytic crackers (cat crackers) operating in the range 400-815°C.
Specifications
AWS A5.9: ER308H
BS EN ISO 14343-A: 19 9 H
BS EN ISO 14343-B: SS308H
DIN 8556 (SG X5CrNi 19 9 (1.4302))