8630 Mod is a low alloy steel that is used in wellhead equipment, blowout preventers, and hangers requiring deep hardening strength with excellent impact resistance. It is a heat treatable alloy steel that contains nominally .30% Carbon, with .90% Chromium, .80% Nickel and .40% Molybdenum as the primary hardening elements.
This alloy is considered an upgrade over 4130 because it maintains good strength and excellent impact properties deep into the product.
80,000 psi or 85,000 minimum yield - limited to a Rockwell C -22 maximum for compliance NACE MR-01-75/ISO 15156 (for use in hydrogen sulfide environments)
Annealed or As-rolled - no mechanical properties; suitable for further heat treatment