Super Austenitic Globe Valves

Common super austenitic stainless steels used in the valve industry are UNS S31254 (254SMO and AL6XN). They are predominantly used to obtain both higher strength and improved resistance to crevice corrosion chloride pitting compared to 316 SS. This improved corrosion resistance comes from the higher Ni and Mo content, and nitrogen strengthens the material. Desalination, food processing, chemical processing, and even seawater services use super austenitic stainless steels as an economical selection in cases where high strength and good corrosion resistance are needed.

Description

Materials Of Super Austenitic Globe Valves

Name	Castings Grades	Forgings Grades	Bars Grades
904L	904L	A182 F904L	B649 N08904
254SMO	A351 CK3MCuN	A182 F44	A276 S31254
AL-6XN	A351 CN3MN	B462 N08367	B688 N08367
ALLOY 20	A351 CN7M	B462 N08020	B473 N08020

Another Type Of Super Austenitic Globe Valves

Another popular super austenitic stainless steel is UNS N08904 (904L), which has a 5% Mo content. It is used for a variety of valve components for inorganic acid environments, typically used in Fertilizer plants with sulfuric and phosphoric conditions. It is also found in the pulp and paper manufacturing, pharmaceutical, and power industries. The material is used mainly for trim components, but new specialized grades with higher strength are also being used for valve pressure–containing components. Sometimes, 904L globe valves can be used for oxygen service.