Last week we had the pleasure of working with a fabricator of pressure vessels in order to help them reduce manufacturing costs. As mandated by the ASME Boiler and Pressure Vessel Code this fabricator had welding procedure specifications (WPSs) and procedure qualification records (PQRs) in place. These were properly written, tested and documented. The WPS […]
Preheating of structural steels is carried out primarily to slow the cooling rate after welding and prevent the formation of martensite. Martensite makes the weld and the heat affected zone (HAZ) very hard and brittle. This newly formed microstructure is susceptible to cracking. By slowing the cooling rate we reduce or eliminate the formation of […]
T-1, or ASTM A514 is a high strength steel which is quenched and tempered to provide yield strengths of over 100,000psi (over 690MPa). The name “T-1” is a trademark of Arcelor Mittal and not an ASTM, AISI or part of other organization’s standard numbering system. ASTM A514 is primarily used as a structural steel and […]
Preheating steel before welding is common practice. Sometimes we apply heat after we are done welding as well. Other times we apply heat between passes to maintain the minimum interpass temperature. Many use preheat simply because it is written in the WPS, but not really understand why it is necessary. Preheating is used for […]
