Key Product Features
- Designed for oil, gas and pipeline isolation service requiring API 6D specification
- Trunnion-mounted design commonly used for larger sizes and higher-pressure pipeline applications
- Floating-ball construction available for selected smaller sizes and pressure classes
- Full-bore or reduced-bore flow passage according to project requirements
- Flanged, butt-weld or project-specific end connections
- DBB, DIB-1 or DIB-2 sealing configuration available when specified and supported by design
- Emergency seat sealant injection and stem sealant injection available by selected model
- Automatic cavity pressure relief or cavity relief system according to seat design
- Manual gearbox, pneumatic, electric, hydraulic or gas-over-oil actuator options
- Fire-safe, anti-static, NACE and stem-extension options available only when specified and confirmed
Product Configuration
| Configuration Item | Common Configuration | Project Options |
|---|---|---|
| Valve Type | Two-way pipeline ball valve | Floating-ball or trunnion-mounted design |
| Pipeline Service | Oil, gas and natural gas pipeline isolation | Pipeline station, compressor station, metering skid or process pipeline service |
| Bore Type | Full bore or reduced bore | Piggable full bore only when confirmed by drawing and project specification |
| End Connection | Flanged or butt-weld ends | Raised face, RTJ, weld-end preparation or project-specific ends |
| Seat Arrangement | Standard pipeline sealing arrangement | DBB, DIB-1 or DIB-2 when specified |
| Sealing System | Soft seat or high-performance seat | Metal seat or severe-service seat after technical review |
| Operation | Gearbox | Pneumatic, electric, hydraulic or gas-over-oil actuator |
Technical Specifications
| Specification Item | Typical / Available Options |
|---|---|
| Product Type | API 6D ball valve / pipeline ball valve |
| Primary Function | Pipeline isolation and emergency shutoff |
| Ball Support | Trunnion mounted or floating ball, depending on selected size and pressure class |
| Body Construction | Split-body, forged, cast, welded-body or top-entry construction according to selected series |
| Bore Design | Full bore or reduced bore |
| Size Range | According to selected API 6D product series and approved drawing |
| Pressure Class | Class 150, 300, 600, 900, 1500 or 2500 when supported by selected design and material |
| Body Material | WCB, A105, LCB, LF2, F304, F316, F51, alloy steel or project-specified material |
| Ball Material | Stainless steel, alloy steel, duplex stainless steel or coated material |
| Stem Material | Stainless steel, alloy steel, duplex stainless steel or project-specified material |
| Seat Material | PTFE, RPTFE, PEEK, PCTFE, metal seat or project-specified seat material |
| Seat Arrangement | Single piston effect, double piston effect, DBB or DIB configuration when specified |
| End Connection | Flanged, butt weld or project-specific pipeline connection |
| Operation | Gearbox, pneumatic actuator, electric actuator, hydraulic actuator or gas-over-oil actuator |
| Design Reference | API 6D and approved project specification when the selected model is ordered as API 6D |
| Testing Reference | API 6D inspection and test requirements, plus project-specific testing when specified |
| Typical Media | Crude oil, refined products, natural gas, process gas, pipeline liquids and selected petrochemical service |
Technical note: Do not publish a fixed size, pressure class, leakage arrangement, fire-safe status or NACE compliance until the selected valve model, material list, project specification and approved datasheet are confirmed. API 6D is a project specification requirement, not a decorative product label.
API 6D Pipeline Valve Design Focus
An API 6D ball valve is different from a general utility ball valve because it is selected for pipeline isolation, long-distance transmission, station service and project-controlled documentation. The design focus is not only quarter-turn shutoff, but also pressure-containing integrity, end connection accuracy, bore requirement, sealing arrangement, inspection, testing and traceability.
| Design Focus | Why It Matters in Pipeline Service |
|---|---|
| Pressure-Containing Body | Must match pressure class, temperature, material and approved design requirements. |
| Full-Bore Requirement | Important for pressure drop, pigging and pipeline operating requirements when specified. |
| Seat Arrangement | Determines DBB, DIB and cavity relief behavior. |
| End Connection | Must match flange standard, RTJ requirement or weld-end preparation. |
| Emergency Sealing | Seat and stem injection fittings can support emergency sealing in selected designs. |
| Actuator Sizing | Pipeline valves may require high torque, fail-safe action or remote operation. |
| Documentation | Material traceability, pressure testing and inspection records are critical for project acceptance. |
Trunnion-Mounted and Floating API 6D Ball Valve Options
Trunnion-mounted construction is commonly selected for larger API 6D pipeline ball valves because the ball is mechanically supported at the top and bottom. This reduces seat load and operating torque under high differential pressure and supports larger-size pipeline isolation.
Floating-ball construction may be used in selected smaller API 6D ball valve sizes and pressure classes. The correct structure should be selected according to valve size, pressure class, seat design, operating torque and project standard.
| Design Type | Main Advantage | Typical API 6D Use |
|---|---|---|
| Floating API 6D Ball Valve | Compact structure for selected smaller pipeline valves | Smaller pipeline or station service where floating design is acceptable |
| Trunnion-Mounted API 6D Ball Valve | Lower torque and stronger ball support for larger or higher-pressure service | Oil, gas, natural gas transmission and pipeline station isolation |
| Top-Entry API 6D Ball Valve | Internal maintenance from the top side of the valve body | Pipeline service where inline maintenance access is required |
For larger high-pressure pipeline isolation, compare our Forged Trunnion Ball Valve. For pressure-focused selection, see the High Pressure Ball Valve.
Full Bore, Reduced Bore and Pigging Requirement
Many pipeline projects require full-bore valves to reduce pressure loss and allow pipeline pigging. However, “full bore” should not be assumed from product name alone. The actual bore diameter, transition geometry, ball port, seat opening and end connection must be confirmed from the approved drawing.
| Bore Type | Main Advantage | Selection Note |
|---|---|---|
| Full Bore | Lower flow restriction and better compatibility with pigging requirements | Piggability must still be confirmed by actual bore and drawing |
| Reduced Bore | Smaller valve body and lower cost in some applications | Not suitable where full pipeline bore or pigging is required |
| Piggable Bore | Supports pipeline cleaning or inspection pig passage | Requires project confirmation of bore, end transition and pig type |
DBB, DIB and Cavity Relief
API 6D ball valves may be requested with DBB or DIB sealing functions, but these terms must not be used loosely. The seat design, piston effect, cavity relief method and test requirement must be defined in the datasheet. A valve described as “double block and bleed” should have the required test and documentation to support the claim.
| Term | General Meaning | Important Confirmation |
|---|---|---|
| DBB | Double block and bleed function for isolation with cavity bleed capability | Confirm seat design, test method and pressure direction |
| DIB-1 | Double isolation and bleed with both seats typically providing bidirectional sealing | Confirm cavity relief arrangement and project acceptance criteria |
| DIB-2 | One seat and the second seat arrangement differ by specified sealing behavior | Confirm exact API 6D datasheet requirement before quotation |
| Cavity Relief | Controls overpressure trapped in the valve body cavity | Confirm automatic relief, external relief or seat relief method |
End Connection Options
| Connection Type | Main Advantage | Typical Pipeline Use |
|---|---|---|
| Flanged API 6D Ball Valve | Removable bolted connection for inspection and replacement | Pipeline stations, metering skids, process units and aboveground installations |
| Butt-Weld API 6D Ball Valve | Permanent welded connection with fewer external joint leak paths | Long-distance pipeline, buried service and critical pipeline sections |
| RTJ Flanged API 6D Ball Valve | Metal ring gasket sealing for higher-pressure flange joints | High-pressure oil, gas and pipeline station service |
| Extended Stem API 6D Ball Valve | Allows operation above ground or above insulation level | Buried pipeline, insulated service or difficult-access installations |
For removable pipeline installation, compare our Flanged Ball Valve. For welded-end pipeline isolation, compare the Butt Weld Ball Valve page after publication.
Material and Seat Options
| Component | Common Options | Selection Consideration |
|---|---|---|
| Body | WCB, A105, LCB, LF2, F304, F316, F51, alloy steel or project-specified material | Pressure class, low-temperature toughness, corrosion, sour service and welding requirement |
| Ball | Stainless steel, alloy steel, duplex stainless steel or coated material | Sealing surface, corrosion resistance, hardness and bore requirement |
| Stem | Stainless steel, alloy steel, duplex stainless steel or project-specified material | Torque transmission, pressure load, corrosion resistance and mechanical strength |
| Seat | PTFE, RPTFE, PEEK, PCTFE or metal seat | Pressure, temperature, gas service, leakage requirement and cavity relief behavior |
| Packing | PTFE, graphite, flexible graphite or low-emission packing | Temperature, fire-safe requirement, fugitive emission and stem cycling |
| Body Seal | Elastomer, PTFE, graphite, spiral-wound gasket or project-specific seal | Body construction, temperature, pressure cycling and fire-safe requirement |
| Bolting | Carbon steel, stainless steel, alloy steel or project-specified bolting | Pressure class, temperature, external corrosion and strength requirement |
Project Options for Oil and Gas Service
Oil and gas pipeline projects often require additional options beyond the basic valve structure. These options should be stated clearly in the inquiry and confirmed against the selected product design.
| Project Option | Purpose | Confirmation Required |
|---|---|---|
| Fire-Safe Design | Supports sealing integrity after fire exposure according to specified test requirement | Applicable fire-safe test standard and certificate scope |
| Anti-Static Design | Provides electrical continuity between ball, stem and body | Design and test evidence if required |
| NACE / Sour Service | Controls material selection for sour oil and gas environments | Applicable NACE / ISO standard, H2S condition and material list |
| Emergency Seat Injection | Allows sealant injection for emergency sealing support in selected designs | Seat design, fitting position and maintenance method |
| Stem Sealant Injection | Supports emergency stem sealing in selected designs | Stem sealing arrangement and fitting details |
| Stem Extension | Allows operation from above ground, above insulation or above platform level | Extension length, drain/vent design and operating method |
| Actuator Package | Provides remote operation, fail-safe action or emergency shutdown | Torque data, power source, control signal and fail position |
Typical Applications
API 6D ball valves are selected where pipeline reliability, shutoff performance and project documentation are important. Common service areas include:
- Crude oil transmission pipelines
- Natural gas transmission and distribution pipelines
- Pipeline block valve stations
- Compressor stations and metering stations
- Pig launcher and receiver isolation
- Tank farm and terminal pipeline isolation
- Refinery and petrochemical pipeline systems
- LNG, gas processing and process gas isolation where material and temperature conditions are confirmed
For broader application planning, review our Industrial Valve Solutions and Ball Valve category.
Application Limits
- API 6D does not automatically mean every valve is piggable; bore and drawing must be checked.
- DBB or DIB function must be specified and verified by seat design and testing.
- Fire-safe, NACE, anti-static and low-emission requirements must be stated before quotation.
- Pipeline gas service requires careful review of leakage, torque, actuator and safety requirements.
- Hydrogen, sour gas, oxygen, CO2-rich gas and toxic media require dedicated material review.
- A standard pipeline ball valve is intended mainly for fully open or fully closed service.
- Continuous throttling may damage seats and increase vibration, noise and torque.
- Actuated pipeline valves require confirmed torque data, fail position and control requirements.
Inspection and Documentation
| Inspection / Document | Purpose |
|---|---|
| Material Test Certificate | Confirms pressure-containing and wetted component material grades and heat numbers. |
| PMI | Verifies alloy material chemistry when specified. |
| Dimensional Inspection | Checks bore, end connection, face-to-face or end-to-end length, flange or weld-end dimensions and actuator interface. |
| Shell Pressure Test | Verifies pressure-containing body integrity. |
| Seat Leakage Test | Confirms shutoff performance under the specified test condition. |
| DBB / DIB Test | Confirms isolation function when DBB or DIB is specified. |
| Cavity Relief Test | Confirms cavity pressure relief function when required. |
| Torque Test | Supports gearbox or actuator sizing and confirms smooth operation. |
| NDE | RT, UT, MT or PT inspection when specified by project requirements. |
| Fire-Safe / Anti-Static Evidence | Provided only when the selected valve model has applicable test or design evidence. |
| Final Data Book | Collects approved drawings, test records, MTCs, inspection reports and certificates for project submission. |
Export packing should protect machined flange faces, RTJ grooves, butt-weld bevels, valve bores, sealant fittings, stem extension and actuator interfaces. Large pipeline valves should be packed with flange covers or weld-end protectors, internal blocking, moisture protection, anti-rust treatment and reinforced export cases according to size and transport method.
Information Required for Valve Selection
- Valve size, quantity and pipeline location
- Pressure class, design pressure and operating pressure
- Design temperature and operating temperature
- Medium: crude oil, natural gas, refined product, process gas or special service
- Gas composition, H2S, CO2, water content and chloride content where relevant
- Required API 6D edition and project specification
- Full-bore, reduced-bore or piggable bore requirement
- DBB, DIB-1, DIB-2 or standard seat arrangement
- Flanged, RTJ flanged or butt-weld end connection
- Body, ball, stem, seat, packing, body seal and bolting materials
- Fire-safe, anti-static, NACE, low-emission or stem-extension requirements
- Manual gearbox, pneumatic, electric, hydraulic or gas-over-oil actuator
- Fail-open, fail-close or fail-last actuator position if automated
- Testing, NDE, third-party inspection and final documentation requirements
FAQ
1. What is an API 6D ball valve used for?
An API 6D ball valve is used for oil, gas, natural gas transmission, pipeline station and process pipeline isolation service where the project requires API 6D valve design, testing and documentation.
2. Is every API 6D ball valve trunnion mounted?
No. Trunnion-mounted construction is common for larger sizes and higher-pressure pipeline service, but floating-ball API 6D designs may be available for selected smaller sizes and pressure classes. The structure must be confirmed from the approved datasheet.
3. Does API 6D mean the valve is automatically full bore and piggable?
No. Full bore and piggable bore must be specified and confirmed by the actual valve drawing, bore diameter and end transition. A valve should not be treated as piggable only because it is described as API 6D.
4. What is the difference between DBB and DIB in API 6D ball valves?
DBB and DIB describe different isolation and bleed functions related to seat sealing behavior and cavity pressure. The exact requirement must be stated in the datasheet and verified by the selected seat design and test procedure.
5. What information is needed for API 6D ball valve quotation?
For quotation, provide valve size, pressure class, medium, temperature, API 6D edition, bore type, end connection, DBB or DIB requirement, material grade, fire-safe or NACE requirement, actuator method, testing scope and documentation requirement.



Typical Applications