Pressure testing of metallic valves ISO standard 5208

International organization for standardization (ISO 5208)

The purpose of ISO standard 5208: Industrial valves - Pressure testing of metallic valves, is the establishment of basic requirements and practices for pressure testing valves of various configurations that are used in general purpose, power generation, petroleum, and petrochemical or allied industry applications. The intent is to provide a consistent set of procedural requirements and acceptance criteria that can be considered in conjunction with valve specific standards appropriate for specific applications. Account has been taken of the valve testing requirement needs of EN 12266 and API 598 with requirements referenced for PN designated valves for the former and Class designated valves for the latter.

Notes:

1. REQ - REQUIRED, OPT - OPTIONAL
2. Successful completion of an optional test does not relieve the manufacturer from also successfully completing the required test.
3. In the case of resilient seated valves, a high-pressure closure test may °rade subsequent closure sealing performance in low-pressure applications.

• (A) Plug valves that rely on a sealing compound to effect a closure seal may be closure tested with the compound installed.
• (B) Successful completion of a BACK SEAT test should not be interpreted as a recommendation by the valve manufacturer that, while an installed valve is pressurized, the stem seal may be altered, repaired or replaced when BACK SEATed.
• (C) In the case of bellows stem sealed valves, a BACK SEAT test is not required.

Notes:
(1) No visually detectable leakage for the duration of the test

1. The leakage rates only apply when discharging test fluid to the atmosphere.
2. The closure leakage rate that applies is either that identified in a valve product standard or a leakage rate identified in a purchaser's valve procurement purchase order that is more stringent than that specified in the product standard.
3. The meaning of "No visually detectable leakage" is that there is no visible weeping or leakage in the form of drops or bubbles.
4. There is a loosely defined correspondence between the leakage rate acceptance values of API 598 and the leakage values Rate A as applied to DN ≤50, Rate AA-Gas and Rate CC-Liquid for other than metal seated check valves and for check valves Rate EE-Gas and Rate G-Liquid. Rates A, B, C, D E, F and G correspond to values in EN 12266-1.