WRC 589:2021 PDF Download

This WRC Bulletin records the data used to gain approval of ASME and API for application of Grade 921 (UNS K91201, 9Cr-2Si-1Cu) alloy at elevated temperatures. This novel alloy has been developed by Vallourec to resist coke formation in refinery heavy oil services and has already gained ASTM (A213 and A335) and ASME (Code Case 3007) approval. All data and property equations are provided herein in both US Customary and Metric units. Included in the data collections and curve fits are yield and tensile strengths, Larson-Miller (LM) stress-rupture properties, and MPC Omega Method properties, including Omega parameter and initial creep strain rate coefficients corresponding to the stresses and temperatures for which data were provided. Also contained within this Bulletin are available data for welded joints, intended to demonstrate the suitability of welded constructions of Grade 921 for elevated temperature service, and establish recommended modifications to the provided base metal properties to account for the behavior of welded joints.