1.1 This specification covers ferritic steel forgings for boilers, pressure vessels, high-temperature parts, and associated equipment. 1.2 Forgings made of steel grades listed in Specification A 335/A 335MThis specification deals with ferritic alloy steel forgings for high-pressure and high-temperature parts, such as boilers, pressure vessels, and associated equipment. The steel grades covered here include the following: Grade F1; Grade F11, Classes 1,