Definition(s)
Low-alloy steel
Steels containing a total alloying element content of less than 5 % mass fraction, but more than that for carbon steel.
EXAMPLES AISI 4130, AISI 8630, ASTM A182 Grade F22[12] are examples of low alloy steels.
Source: API RP 17A Addendum 1, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, December 2010. Global Standards
Source: ISO 21457:2010, Petroleum and natural gas industries — Materials selection and corrosion control for oil and gas production systems, First Edition,September 2010. Global Standards
Low-alloy steel
Steel containing less than 5% total alloying elements, but more than specified for carbon steel. Although not generally considered a low alloy steel, steels with less than 11% chromium shall be included in this category.
Source: API SPEC 16C, Specification for Choke and Kill Systems, First Edition, January 1993 (Reaffirmed 2001). Global Standards