Heat treatment requiring heating, one or more times, to a specific temperature below the lower critical temperature and holding at that temperature. NOTE 1 Tempering is often preceded by quench hardening. NOTE 2 Adapted from ISO 4885.
Source: API SPEC 5CRA, Specification for Corrosion Resistant Alloy Seamless Tubes for Use as Casing, Tubing and Coupling Stock, Upstream Segment, First Edition, February 2010 (Errata August 2011). Global Standards