API 6A Trunnion Ball Valves — 6000PSI

Description

Technical Data Sheet

API 6A Trunnion-Mounted Ball Valve — 6000 PSI

Valve Type: Trunnion-Mounted Ball Valve, Side-Entry, Forged Construction
Product Designation: API 6A Trunnion Ball Valve
Example Model: TBV-6000-3116-RTJ-6A
Nominal Size: 3-1/8″ (selected as representative example)
Pressure Rating: 6,000 psi (41.4 MPa)
Operation: Gear Operated (standard); lever, pneumatic, hydraulic or electric actuation available upon request

1. Design Standards & Compliance

Item Standard / Requirement
Design & Manufacturing API Specification 6A / ISO 10423, 21st Edition
Pressure-Temperature Rating ASME B16.34
Product Specification Level (PSL) PSL 1, 2, 3, 3G, 4 (project-specific)
Performance Requirement (PR) PR 1 (Standard closure), PR 2 (High-cycle/stringent closure)
Material Class AA, BB, CC, DD, EE, FF, HH (per API 6A / NACE MR0175)
Temperature Class L, N, P, R, S, T, U, V, X, Y (−50°F to +350°F / −46°C to +177°C)
Fire-Safe Design API 6FA / API 607 / BS 6755 Part 2
Sour Service Compliance NACE MR0175 / ISO 15156 (Sour Service), as applicable
End Connections API 6A Type 6B Flanges with Ring Joint (RTJ), Buttweld, Hubbed, Clamp Connectors
Top Flange Mounting ISO 5211 (for direct actuator mounting)
2. Valve Configuration

Parameter Specification
Nominal Bore 3-1/8″ (79.4 mm); available range 1-13/16″ to 20-1/4″
Working Pressure 6,000 psi (41.4 MPa); available range 2,000 psi to 20,000 psi
Bore Type Full Bore or Reduced Bore (Full Bore Standard)
Body Type Two-piece or Three-piece bolted body, Forged Steel construction
Ball Design Trunnion-Mounted Ball — supported by fixed upper and lower trunnions, minimizing deformation under high pressure
Seat Design Spring-assisted / Pressure-assisted floating seats; Bi-directional sealing
Piston Effect Options Single Piston Effect (SPE) / Double Piston Effect (DPE) / Double Block and Bleed (DBB) functionality
Flow Direction Bi-directional (Standard) or Unidirectional
Sealing Class Soft Seated: Zero Leakage (API 6A / ISO 5208 Rate A); Metal Seated: FCI 70-2 Class 5 or Class 6
Body Cavity Relief Automatic — Upstream seat disengages when cavity pressure exceeds 1.33× rated pressure
3. Materials of Construction — Standard Trim Configurations

The table below presents commonly specified material configurations for API 6A trunnion ball valves. Material class shall be selected based on service conditions (general, sour, corrosive) and PSL requirements. All materials must comply with NACE MR0175 requirements based on PSL and sour service conditions.

Component Standard Material (Carbon Steel) Corrosion-Resistant / Special Alloy Options
Body / Bonnet Carbon Steel (e.g., AISI 4130, ASTM A694 F60/F65, 60K, 75K) Stainless Steel (316/316L), Duplex Stainless Steel, Alloy 625 (Inconel)
Ball / Trunnion / Stem Stainless Steel (AISI 410 / 17-4PH) + Coating (Nitriding / ENP) Stainless Steel + Stellite 6 Hardfacing / Tungsten Carbide Coating (HVOF) / Inconel 625
Seat Support Ring Carbon Steel / Stainless Steel Stainless Steel + Stellite Hardfacing
Seal Ring (Insert) PTFE, PEEK, Nylon, Devlon (self-lubricating) Reinforced PTFE / Metal-to-Metal (with Graphite) / Hardfaced STL
Bearings / Bushings Self-lubricating Composite Material (e.g., PTFE composite) Tungsten Carbide coated journals
Stem / Trunnion Sealing NBR, FKM (Viton), HNBR FFKM (Chemraz/Kalrez), PTFE Spring-Energized Lip Seals
Bonnet Seal AISI 1018/1020 Low Carbon Steel / Soft Metallic Crush Ring AISI 304 or 316 Stainless Steel + Graphite
Bolting ASTM A193 B7 / A194 2H (or equivalent), PTFE coated ASTM A193 B7M / A194 2HM (Sour Service), ASTM A193 B8M / A194 8M (Stainless)
External Coating Epoxy Paint (standard) Special coatings upon request
Material Class Reference (per API 6A):

Material Class Service Condition Body Material Trim
AA General Service, Non-Corrosive API 60K/75K, AISI 4130 Standard Trim (Nitrided)
BB General Service, Slightly Corrosive API 60K/75K, AISI 4130 Stainless Trim (410/17-4PH)
CC General Service, Moderately Corrosive API 75K, AISI 410 SS Full Stainless Trim
DD Sour Service, Non-Corrosive API 60K/75K, AISI 4130 Standard Trim (Nitrided)
EE Sour Service, Moderately Corrosive API 60K/75K, AISI 4130 Stainless Trim (410/17-4PH)
FF Sour Service, Highly Corrosive A182 F22/F316/F6a Inconel 625 + Stellite
HH Sour Service, Severely Corrosive Alloy 625 / Special Alloys Alloy 625 / Special Alloys
Source: Adapted from API 6A Valve Material Specification tables and industry practice.

4. Dimensions & Weights — 6,000 psi, RTJ Flanged End

Nominal Size Bore Size (in) Face-to-Face (L) (mm) Center to Top (H) (mm) Approx. Weight (kg)
2-1/16″ 2.09 295 450 70
2-9/16″ 2.59 333 500 85
3-1/8″ 3.22 359 550 120
4-1/16″ 4.09 400 620 180
*Dimensions per API 6A flanged-end trunnion ball valves for 6,000 psi working pressure.*

Notes:

Face-to-face dimensions comply with ASME B16.10 or manufacturer‘s standard per API 6A.
Gear operator is standard for sizes 4″ and above; lever operation is standard for smaller sizes.
Exact dimensions and weights may vary by manufacturer and body configuration (2-piece vs. 3-piece).
5. Flange Connection Data — Representative for 3-1/8″ 6,000 psi

Parameter Specification
Flange Type API 6A Type 6B Flange with Ring Joint (RTJ)
Ring Gasket Type R or RX (size per API 6A)
Connection Raised Face Ring Joint (RTJ), complete with companion flanges, ring joint gasket, studs and nuts
Flange Material Compatible with body material; Forged Carbon Steel / Alloy Steel (60K/75K) or Stainless Steel
6. Testing & Inspection

Test Item Test Medium Test Pressure Standard
Shell Hydrostatic Test Water 1.5 × Rated Working Pressure (9,000 psi / 62.1 MPa) API 6A
Seat Hydrostatic Test Water 1.1 × Rated Working Pressure (6,600 psi / 45.5 MPa) — Both directions API 6A
Seat Gas Test Air / Nitrogen 0.55–1.1 MPa (Low Pressure) & Maximum Rated Pressure API 6A
Double Block & Bleed (DBB) Test Water / Gas As per API 6A API 6A
Fire Test — Per API 6FA / API 607 API 6FA / API 607
NDE (Non-Destructive Examination) — MPI / LPI / RT (As per PSL requirements) API 6A
Visual & Dimensional — — MSS SP-55, ASME B16.10
Drift Test — — API 6A
Hold Duration: Minimum 15 minutes per test; PSL 3G and PSL 4 include enhanced requirements such as witnessed material tests and extended hold periods.

Documentation:

Material traceability and test reports available per EN 10204 3.1 or 3.2
PSL 2 or higher provides enhanced QA traceability, including traceable MTRs by heat number, witnessed pours and witnessed material tests
API 6A Monogram certification available
7. Design Features

Trunnion-Mounted Ball Design: The ball is supported by fixed upper and lower trunnions (shafts), minimizing ball deformation under high pressure and reducing operating torque compared to floating ball designs.
Full Through-Conduit Bore: Provides smooth flow with minimal turbulence; unobstructed passage for well intervention tools and pigging operations.
Double Block & Bleed (DBB) Capability: Two independent seating surfaces provide positive isolation in both directions with cavity bleed verification.
Independent Floating Seat Rings: Two independent floating seat rings assure bi-directional tightness from zero differential pressure to maximum rated pressure.
Anti-Static Device: Springs between ball and stem/body ensure electrical continuity (<10Ω), preventing static electricity buildup — essential for flammable/explosive service. Fire-Safe Design: Certified to API 6FA / API 607 / BS 6755 Part 2; ensures sealing integrity during and after fire exposure. Blowout-Proof Stem: Stem designed with integral collar to prevent ejection under line pressure, ensuring operator safety. Emergency Sealant Injection System: Seats can be lubricated/repaired from grease injection fittings to reduce abrasion and extend service life. Automatic Body Cavity Relief: Upstream seat disengages when cavity pressure exceeds 1.33 times the rated pressure, preventing over-pressurization due to thermal expansion. Sour Service Capability: Available with NACE MR0175 / ISO 15156 compliant materials for H₂S/CO₂ containing media. Double Piston Effect (DPE) Option: Both upstream and downstream seats are pressure-energized, providing bi-directional sealing regardless of pressure direction; suitable for critical isolation and double block and bleed applications. 8. Actuator Mounting (Upon Request) Mounting Pad: ISO 5211 standard flange integrated on valve top for direct actuator mounting. Stem Top: Machined with keyway or square per actuator coupling requirements. Actuator Types: Manual (lever/gear), Pneumatic Actuator (double-acting or spring-return), Motor Actuator (multi-turn electric), Hydraulic Actuator; mounting bracket and stem coupling provided. Manual Override: Available (handwheel or gear override). Accessories: Limit switches, solenoid valves, positioners, gearboxes, and partial-stroke testing devices available as a package. 9. Service & Application Parameter Specification Service Medium Crude Oil, Natural Gas, Well Fluids, H₂S/CO₂ containing media Applications Oil and gas wellhead equipment, Christmas trees, pipelines, choke and kill manifolds, production manifolds, high-pressure isolation, and harsh environments (including H₂S/CO₂ sour service, high pressure, high/low temperature) Working Temperature −50°F to +350°F (−46°C to +177°C); extended ranges available upon request Flow Direction Bi-directional (Standard) 10. Ordering Information When ordering, please specify: Nominal Size (e.g., 3-1/8″) and Pressure Rating (6,000 psi) Material Class (AA / BB / CC / DD / EE / FF / HH) based on service conditions Product Specification Level (PSL): PSL 1, 2, 3, 3G, or 4 Performance Requirement (PR): PR 1 or PR 2 Temperature Class (K, L, N, P, R, S, T, U, V, X, Y) NACE MR0175 Compliance: Required (Yes/No) Bore Type: Full Bore or Reduced Bore End Connection: RTJ Flanged, Buttweld, Hubbed, Clamp Connector Seat Type: Soft Seated (PTFE/PEEK/Nylon/Devlon) or Metal Seated (STL/TCC Hardfacing) Piston Effect Configuration: Single Piston Effect (SPE) / Double Piston Effect (DPE) / DBB / DIB Operation: Manual (lever/gear), Pneumatic, Electric, Hydraulic Actuator — specify actuator brand, power supply/air pressure, control signal Fire-Safe Certification: Required (Yes/No) Fugitive Emission Certification: Required (Yes/No) Special Coatings or Surface Treatments: e.g., QPQ, Nitriding, ENP, TCC/STL Hardfacing, Epoxy Paint Documentation Level: EN 10204 3.1 / 3.2 certificates, PMI, NDE (MPI/LPI/RT), Charpy Impact Test Results