API St 598-2009 pdf free download

API St 598-2009 pdf free download.Valve Inspection and Testing.
1 Scope 1.1 This standard covers inspection, examination, supplementary examinations, and pressure test requirements for resilient-seated, nonmetallic-seated (e.g. ceramic), and metal-to-metal-seated valves of the gate, globe, plug, ball, check, and butterfly types. Resilient seats are considered to be: a) soft seats, both solid and semi-solid grease type (e.g. lubricated plug); b) combination soft and metal seats; c) any other type valve designed to meet resilient seat leakage rates as specified in Table 6. API 598 supplements the API standards that reference it, but it may also be applied to other types of valves by agreement between the purchaser and the valve manufacturer. 1.2 The inspection requirements pertain to examinations and testing by the valve manufacturer and any supplementary examinations that the purchaser may require at the valve manufacturer’s plant. The test requirements cover both required and optional pressure tests at the valve manufacturer’s plant, or at a facility mutually agreeable to both the manufacturer and purchaser. 1.3 The following tests and examinations are specified in this standard: a) shell test, b) backseat test, c) low-pressure closure test, d) high-pressure closure test, e) double block and bleed high-pressure closure test, f) visual examination of castings by the manufacturer, g) high-pressure pneumatic shell test. 2 Normative References The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. API Standard 594, Check Valves: Flanged, Lug, Wafer and Butt-welding API Standard 599, Metal Plug Valves—Flanged, Threaded and Welding Ends API Standard 600, Steel Gate Valves—Flanged and Butt-welding Ends, Bolted Bonnets API Standard 602, Steel Gate, Globe and Check Valves for Sizes DN 100 and Smaller for the Petroleum and Natural Gas Industries
3.7 nominal pipe size NPS An alpha numeric designation of size that is common for components used in a piping system, used for reference purposes, comprising the letters NPS followed by a dimensionless number indirectly related to the physical size of the bore or outside diameter of the end connection as appropriate. The dimensionless size identification number following NPS does not represent a measurable value and is not used for calculation purposes except where specified in ASME B16.34. Prefix NPS usage is applicable to steel valves bearing class designations. 3.8 shell test A pressure test in excess of the cold-working-pressure, CWP, rating of the valve for the purpose of validating the soundness and strength of the valve pressure containing structures. 3.9 visually detectable leakage Leakage during a valve pressure test, either through or past a pressure boundary or closure member that is validated by normal vision. 4 Inspection, Examination, and Supplementary Examination 4.1 Inspection at the Valve Manufacturer’s Plant The purchaser shall specify in the purchase order his intention to inspect valves and witness tests and examinations at the valve manufacturer’s plant. The purchaser’s inspector shall have free access to any part of the plant concerned with manufacture of the valves whenever work on the order is under way. 4.2 Inspection Outside the Valve Manufacturer’s Plant When the valve purchaser specifies that the inspection will include shell components manufactured at locations other than the valve manufacturer’s plant, these components shall be subject to the valve purchaser’s inspection at the location where they are manufactured. 4.3 Inspection Notice When inspection by the purchaser is specified, the valve manufacturer shall notify the purchaser five working days prior to the required valve testing and any specified supplementary inspections or examinations, addressing the notice as stated in the purchase order.
4.4 Extent of Inspection The extent of inspection may be specified in the purchase order and, unless otherwise indicated, will be limited to the following. a) Inspection of the valve during assembly to ensure compliance with the specifications of the purchase order. Inspection may include the use of specified nondestructive methods. b) Witnessing of the required and specified optional pressure tests and examinations.