Selectarc B691NM

The Selectarc B691NM is a low hydrogen basic coated electrode specifically designed for welding creep-resistant steels, notably P91 (known as 1.7386 or 1.7389). It’s ideal for applications requiring high temperature resistance up to 650°C, commonly used in power plants, heat exchangers, tubes, and steam boilers. This electrode provides a deposit resistant to temperature and creep, as well as hot gas and overheated steam, and is particularly suited for welding castings with Mn+Ni<1.0%. The weld metal composition, after heat treatment, offers controlled levels of carbon, silicon, manganese, chromium, nickel, molybdenum, and other elements, contributing to its exceptional performance.

This electrode is primarily used for welding creep-resistant steels, particularly P91, in high-temperature applications. The recommended welding procedure involves a slow cooling cycle after heat treatment (760°C / 2h) and specific interpass temperature control (200-300°C) to ensure optimal weld quality and mechanical properties. Careful control of cooling rates and layer thicknesses (approximately 2mm) is crucial for achieving enhanced impact resistance. It’s particularly suited for applications in power plants and high-pressure vessel fabrication.