scope:

This Recommended Practice (RP) provides guidelines for reconditioning of API Standard 594, API Standard 599, API Standard 600, API Standard 603, API Standard 608, API Standard 609, and API Standard 623 valves. Guidelines contained in this RP apply to flanged and butt weld cast or forged valves. Parts of this standard may also be applied to other valves not specifically addressed with agreement between the Owner and the valve Reconditioner.

This RP does not cover reconditioning or remanufacturing of used or surplus valves intended for resale. It does not cover the modification of new valves (e.g. converting or changing the trim). For modification of new valves, see MSS SP-141, Multi-Turn and Check Valve Modifications. Electric and pneumatic actuator repair and reconditioning are not included in the scope of this document. The only intent of this RP is to provide guidelines for refurbishing an end user's (Owner) valves for continued service in the Owner's facility. Valves reconditioned to this RP may not meet API Standard requirements for new valves. The correct application of a valve reconditioned to this RP remains the responsibility of the Owner.