1.1 ,This specification2 covers five grades of bolting materials with twelve classes of yield strength ranging from 50 to 120 ksi [345 to 827 MPa] for use in high-temperature service for bolting components, such as bolts, screws, nuts, or studs, for pressure vessel and valve flanges. See Specification A962/A962M for the definition of bolting. The material requires special processing and is not intended for general purpose applications.