API RP 591

Annotation of standard text API RP 591 :

This recommended practice provides recommendations for evaluation of a manufacturer’s valve construction for the purpose of determining a manufacturer’s capability to provide new valves manufactured in accordance with the applicable standards listed in Section 2.
Evaluation of valves under this RP is “manufacturing facility specific” and does not cover valves manufactured by other manufacturing facilities, whether owned by the same manufacturer or a third party. See more