ASME B16.34 is a general foundational standard applicable to steel valves with flanged, threaded, or welded ends (including gate valves, globe valves, ball valves, check valves, etc.).
It primarily specifies general technical conditions-such as pressure-temperature ratings, material requirements, dimensions, and test methods-but does not address specific details regarding valve structural design.
API 6D is a specialized specification specifically tailored to pipeline valves used in the oil and gas industry (such as ball valves, gate valves, plug valves, and check valves).
Its scope is more comprehensive, encompassing design, manufacturing, testing, inspection, operation, maintenance, and documentation; it places particular emphasis on requirements specific to pipeline applications, such as fire safety, bi-directional sealing, automatic pressure relief, and face-to-face dimensions.
Choosing Your Standard: A Decision Matrix for API 6D vs ASME B16.34 Valves.
Technical Specification Table: API 6D Pipeline Valves
| Parameter | Description / Specifications |
| Design Standard | API Spec 6D / ISO 14313 |
| Main Valve Types | Ball Valve, Gate Valve, Check Valve, Plug Valve |
| Size Range | NPS 2" ~ NPS 60" (DN 50 ~ DN 1500) |
| Pressure Class | Class 150, 300, 400, 600, 900, 1500, 2500 |
| Working Temperature | -196°C ~ 550°C (Subject to material selection) |
| Product Specification Level | PSL 1, PSL 2, PSL 3, PSL 3G |
API 6D Pipeline Valves Material Specifications
| Component | Common Materials |
| Body / Bonnet | WCB, LCB, LCC, CF8, CF8M, CF3, CF3M, A105, LF2, F316, F51, F53 |
| Ball / Gate | A105+ENP, F316, F304, F51, Monel, Inconel |
| Seat | Soft Seat: PTFE, RPTFE, PEEK, DEVLON, NYLON / Metal Seat: STL, WC Coating |
| Stem | 13Cr, F304, F316, 17-4PH, XM-19, F51, Inconel |
| O-Ring / Gasket | Viton (A/B/GLT), NBR, HNBR, PTFE, Flexible Graphite |
Technical Specification Table: ASME B16.34 Valves
| Parameter | Description / Specifications |
| Full Standard Name | ASME B16.34: Valves-Flanged, Threaded, and Welding End |
| Size Range | NPS 1/2" ~ NPS 60" (DN 15 ~ DN 1500) |
| Pressure Class | Class 150, 300, 400, 600, 900, 1500, 2500, 4500 |
| Class Designations | Standard Class: For general industrial applications <br> Special Class: Requires mandatory NDT; for severe service <br> Limited Class: For small bore welding-end valves only |
| End Connections | Flanged (RF/RTJ), Butt-welding (BW), Socket-welding (SW), Threaded (NPT) |
Material Grouping (Per Table 1 of ASME B16.34)
| Material Group | Representative Materials |
| Group 1.1 | Carbon Steel: A105, A216 WCB, A350 LF2 |
| Group 1.2 | Carbon Steel / Low Alloy: A216 WCC, A352 LCC |
| Group 1.9 / 1.10 | Cr-Mo Alloy: A182 F11, F22, A217 WC6, WC9 |
| Group 2.1 / 2.2 | Austenitic Stainless Steel: A182 F304, F316, A351 CF8, CF8M |
| Group 3.x | High Alloy / Nickel Alloy: Monel, Inconel, Hastelloy |
API 6D VS ASME B16.34 Valve Comparison Table
| Feature | API 6D | ASME B16.34 |
| Industry | Midstream (Pipelines) | General Industrial (Refining/Power) |
| Pigging | Yes, Full Bore mandatory | No, not a priority |
| Leak Testing | More Rigorous (Longer durations) | Standard (API 598/MSS SP-61) |
| Valve Types | Ball, Gate, Check, Plug | All types (including Globe/Butterfly) |
| DBB/DIB | Defined & Required | Not Defined |
| Traceability | High (PSL 1, 2, 3) | Standard |
GNEE API 6D Valve factory
FAQ
What is the 6D standard?
API 6D is a standard that delineates the minimum requirements for the design and performance of valves used in pipeline systems, particularly in the oil and gas sector. The standard is intended to ensure that valves can safely and effectively control the flow of fluids under varying pressure and temperature conditions.
What is an API 6D valve?
API 6D (Pipeline Valves): This standard primarily focuses on pipeline valves, which include gate, plug, and ball valves. These valves are specifically designed to transmit and distribute oil, gas, and other hydrocarbons in pipeline systems.