G-TECH 16.8.2

The consumables of subfamily 16.8.2 are characterized by a composition and ferrite control skillfully designed to ensure exceptional performance in service conditions at temperatures up to about 800 °C and cryogenic toughness down to -196 °C. With molybdenum (Mo) precisely at the lower limit for AWS 16.8.2, these materials represent a hybrid between E308H and E316H. They are employed in the welding of "3XXH" series stainless steels, valued for their resistance to creep, oxidation, and general corrosion. The low overall Cr+Mo content, associated with precise control of carbon (C) and ferrite, ensures high resistance to thermal embrittlement caused by intermetallic phases, significantly enhancing ductility and thermal fatigue. It is crucial that these consumables do not include components containing bismuth (Bi), keeping Bi <0.002% as required by API 582 standards. This filler metal is developed to prevent issues associated with Heat-Affected Zones (HAZ) in applications involving 347H and 321H steels with thicknesses greater than 12 mm. Such applications include
catalytic crackers, cyclones, transfer lines, furnace components, thick-walled steam pipes, superheater headers, and some components of gas and steam turbines. These materials find widespread use in petrochemical, chemical, and power generation sectors. No preheating is required, and the maximum interpass temperature is 250 °C. The welds are kept in the "as welded" condition, requiring no post-weld heat treatment (PWHT).