Astm A307 Specification -

: Originally used for unheaded anchor bolts (bent or straight) for structural anchorage. This grade was officially withdrawn in 2007 and replaced by the ASTM F1554 Grade 36 specification . Mechanical & Chemical Requirements

Specifically for flanged joints in piping systems, particularly those using cast iron flanges. Strength: A specified range of 60,000 to 100,000 psi . astm a307 specification