API 6D:2002 pdf download

API 6D:2002 pdf download.Pipeline Valves.
6.7 Valve ends
6.7.1 Flanged ends
Standard end flanges shall be furnished with a raised lace or flng joint faces (rajsed lace or lull lace). Dirnensons, tolerances and finishes, including drilling templates, flange facing, spot facing and back facing, shall be in accordance with:
– ASME B16.5 for sizes up to and including DN 600 (NPS 24), except DN 550 (NPS 22); MSS SP-44 for DN 550 (NPS 22):
ASME 816.47 Series A for DN 650 (NPS 26) and larger sizes.
6.7.2 Welding ends
Welding ends shall conform to Fgures 434.86 (a) (1) and (2) of ASME B31.4 or Figures 14 and 15 of ASME B31.8 unless otherwise agreed In the case of a heavy-wall valve body, the outside profile may be tapered at 30° and then to 45° as illustrated in Figure 1 of ASME 816.25.
The purchaser shall specify the outside diameter, wall thickness, material grade. SMYS and special chemistry of the mating pipe, and whether cladding has been applied.
6.7.3 SpecIal flanges and mechanical loints
Other end connections, such as special flanges or mechanical joints. may be specified by the purchaser.
6.8 Pressure relief
The manufacturer shall determine whether fluid can become trapped in the body cavity lithe open- and/or closed valve position.
I fluid trapping is possible, then valves for gas seivice. unless otherwise specified by the purchaser, and liquid sorvce shall be provided with an automatic cavity pressure relief.
Cavity relief, when required, shall prevent the pressure in the cavity from exceeding 1,33 times the valve pressure rating determined in accordance with 6.1 for material 38°C (100°F). Ecternal cavity relief valves shall be DN 15 (NPS ‘/2) or larger.
6.9 Bypass, drain and vent connections
Bypass. drain and vent connections and plug entries shall be drilled and threaded unless otherwise specified. The purchaser may specify other types of connections, such as welded or flanged.
Threads shall be either tapered and capable of providing a pressure-tight seal or parallel-threaded. Connections or plugs with paralel threads shal have a head section for trapping and retaining a sealing member suitable for the specified valve seMce
Thread sizes shall be in accordance with Table 7. Thread forms shall be in accordance with ASME 81.1, ASME 8120.1. lSO228-1, 1S0228-2 or 1S07-1.
6.17.3 Allowable deflections
For ball valves, the total tors4onal deflection of the extended drive train when delivering the design torque shall not exceed the overlap contact angle between the seat and obturator.
Deflections of the extended dnve train shall not prevent the obturator from reaching the fully closed position.
6.18 Stem retention
Valves shall be designed with a stem anti-blow-out device to prevent stem eechon by internal pressure when the stem packing an&or retainer has been removed.
6.19 Fire safety
If specified by the purchaser, fire resistance certification of the design shall be provided, in accordance with clause A.5.
6.20 Anti-static device
I specified by the purchaser, valves shall be provided with an anti-static device and tested in accordance with clause C.5.
6.21 Design documents
The design shall be documented in a retrievable and reproducible form,
6.22 Design document review
Design documentation shal be reviewed and verified by competent personnel other than the person who
performed the original design.
7 Materials
7.1 MaterIal specification
MaterEals shall be procured to documented specifications.
Specifications for metallic parts shall, as a mirNmum, specify the requirements for:
— chemical properties:
— heat treatment;
— mechanical properties:
— testing;
— certification.
Metallic pressure-containing parts, excep stems and gaskets. shall be made of rnatenals listed in ASME BI 6.34 or, by agreement, an equivalent standard.
7.2 Service compatibility
All process-wetted parts, metallic and non-metallic, and lubricants shall be suitable for the commissioning fluids and service specified by the purchaser.
Non-metallic parts of valves intended for hydrocarbon gas service at pressures of PN 100 (Class 600) or above shall be resistant to explosive decompression.