Session: MF-25-01 High Strength Steels for Pressure Vessels and Piping Applications

Paper Number: 107297

107297 - Impact Test Exemption Temperature Reduction of Sa-193 B16 Studs for Cold Climate Installations 

SA-193 B16 studs are more cost effective and more reliable in high temperature equipment applications than B8 studs, however B16 stud applications are currently limited in a significant portion of North American and other places in the world colder climates due to the current -20F (-30C) impact test exemption temperature in ASME Section VIII, B31, and FFS-1. Furthermore, MDMT adjustments are not permitted for studs due to preload [e.g., UCS-66(b)]. ASME BPVC Section VIII Division 1 specifies an impact test exemption temperature for SA-193 B7 of -55F (-48C) for up to 2 ½” (64 mm) studs, whereas SA-193 B16 studs have a higher impact test exemption temperature of -20F (-30C) up to 7” (175 mm) studs.

The similar material and chemical properties of B16 and B7 studs (both SA-193) give reason to believe that both stud types should exhibit similar fracture toughness properties at low temperatures. Two phase research and testing programs have been running for the past few years. The initial research and testing were performed on one sample material to determine if the MDMT for B16 and B7 studs was similar at low temperatures for small diameters.  Part of this feasibility study involved developing impact test transition curves through Charpy impact testing, as well as fracture toughness testing, which will be detailed in this paper.

Then the second part of the program was about statistical sampling with material sourced from around the world.

Presenting Author: Yunior Hioe Engineering Mechanics Corporation of Columbus

Presenting Author Biography: Dr. Hioe spent his last 12 years at Emc2 working in experimental design and instrumentation of physical, mechanical, thermal, and chemical characterization of advanced materials serving both Oil&Gas and Nuclear Industry. He is also the Director of Laboratory Operation which includes structural testing to characterize full-scale failure behavior of pipeline and pressure boundary components including high energy full scale burst tests conducted at Emc2’s remote location near Mojave, CA. Prior his time at Emc2 he was an NSF-NSEC (National Science foundation Nanoscale Science and Engineering Center) fellow at the Ohio State University with background research in nano reinforcement of fiber reinforced composite materials.

Authors:

Yunior Hioe Engineering Mechanics Corporation of Columbus
Fabian Orth Engineering Mechanics Corporation of Columbus
Kenneth Bagnoli Engineering Mechanics Corporation of Columbus
Sabastian Moncayo ExxonMobil Research and Engineering