690 alloy has excellent resistance to intergranular corrosion and intergranular stress corrosion cracking, and is mainly used in pressurized water nuclear power plant steam generator heat transfer tube material. Pressurized water reactor nuclear power plant steam generator heat transfer pipe materials have gone through a development process, including 304 austenitic stainless steel,600 alloy, 800 alloy and 690 alloy. The study on corrosion failure of 600 alloy in service shows that intergranular corrosion and intergranular stress corrosion cracking are the main problems. 690 alloy as a pressurized water reactor nuclear power plant steam generator heat transfer tube material, since the 1990s has been put into use has not been found damaged reports.
The rim has numerous holes drilled into it that enables the flanged to be attached to a bolted flange. This design is far better because of the structural valve.





















