API 6A Weld Neck RTJ Flange manufacturer
What is API 6A Weld neck flanges?
Weld neck flange made according to API 6A standard,API 6A Weld Neck Flanges are high-pressure pipe flanges specifically designed to meet the requirements of API Specification 6A, which governs equipment used in wellhead and Christmas tree systems for oil and gas drilling and production.
About API 6A Standard
API Specification 6A / ISO 10423 Petroleum and natural gas industries – Drilling and production equipment – Wellhead and christmas tree equipment
This International Standard specifies requirements and gives recommendations for the performance, dimensional and functional interchangeability, design, materials, testing, inspection, welding, marking, handling, storing, shipment, purchasing, repair and remanufacture of wellhead and christmas tree equipment for use in the petroleum and natural gas industries.
This International Standard does not apply to field use, field testing or field repair of wellhead and christmas tree
equipment.
Download the latest editions of pdf format API 6A standard
Specification of API 6A Weld Neck Flanges:
- Design Standard:
- Conforms to API 6A, which specifies flanges suitable for critical pressure service—often from 2,000 PSI up to 20,000 PSI.
- Weld Neck Connection:
- These flanges have a long tapered hub that is welded to the pipe, providing excellent stress distribution and reinforcement in high-pressure systems.
- RTJ (Ring Type Joint) Facing:
- Typically have a Ring Type Joint (RTJ) face for metal-to-metal sealing
- Pressure Classes:
- Available as Type 6B and 6BX:
- 6B flanges are rated up to 5,000 PSI.
- 6BX flanges go up to 20,000 PSI and are used where higher integrity is required.
- Available as Type 6B and 6BX:
- Materials:
- Common materials include API 60K, AISI 4130, ASTM A694 F60/F65
- Inconel 625, and ASTM A105, suitablefor sour service (H2S environments),comply with NACE MR0175 standards.
- Size Range:
| Flange Size | Working Pressure (PSI) | Outside Diameter | Number of Bolt Holes | Diameter of Bolt Holes | Length of Bolts | API Ring Gasket |
|---|---|---|---|---|---|---|
| 1-13/16″ | 10,000 | 7-3/8″ | 8 | 3/4″ | 5-1/4″ | BX-151 |
| 1-13/16″ | 15,000 | 8-3/16″ | 8 | 7/8″ | 6″ | BX-151 |
| 1-13/16″ | 20,000 | 10-1/8″ | 8 | 1″ | 7-3/4″ | BX-151 |
| 2-1/16″ | 2,000 | 6-1/2″ | 8 | 5/8″ | 5/8″ | R-23 |
| 2-1/16″ | 3,000/5,000 | 8-1/2″ | 8 | 7/8″ | 7/8″ | R-24 |
| 2-1/16″ | 10,000 | 7-7/8″ | 8 | 3/4″ | 3/4″ | BX-152 |
| 2-1/16″ | 15,000 | 8-3/4″ | 8 | 7/8″ | 7/8″ | BX-152 |
| 2-1/16″ | 20,000 | 11-5/16″ | 8 | 1-1/8″ | 1-1/8″ | BX-152 |
| 2-9/16″ | 2,000 | 7-1/2″ | 8 | 3/4″ | 5-1/4″ | R-26 |
| 2-9/16″ | 3,000/5,000 | 9-5/8″ | 8 | 1″ | 7″ | R-27 |
| 2-9/16″ | 10,000 | 9-1/8″ | 8 | 7/8″ | 6-1/4″ | BX-153 |
| 2-9/16″ | 15,000 | 10″ | 8 | 1″ | 7″ | BX-153 |
| 2-9/16″ | 20,000 | 12-13/16″ | 8 | 1-1/4″ | 9-1/2″ | BX-153 |
| 3-1/8″ | 2,000 | 8-1/4″ | 8 | 3/4″ | 5-1/2″ | R-31 |
| 3-1/8″ | 3,000 | 9-1/2″ | 8 | 7/8″ | 6-1/4″ | R-31 |
| 3-1/8″ | 5,000 | 10-1/2″ | 8 | 1-1/8″ | 7-3/4″ | R-35 |
| 3-1/16″ | 10,000 | 10-5/8″ | 8 | 1″ | 7-1/4″ | BX-154 |
| 3-1/16″ | 15,000 | 11-5/16″ | 8 | 1-1/8″ | 8″ | BX-154 |
| 3-1/16″ | 20,000 | 14-1/16″ | 8 | 1-3/8″ | 10-3/4″ | BX-154 |
| 4-1/16″ | 2,000 | 10-3/4″ | 8 | 7/8″ | 6-1/4″ | R-37 |
| 4-1/16″ | 3,000 | 11-1/2″ | 8 | 1-1/8″ | 7-1/2″ | R-37 |
| 4-1/16″ | 5,000 | 12-1/4″ | 8 | 1-1/8″ | 8-3/8″ | BX-155 |
| 4-1/16″ | 20,000 | 17-9/16″ | 8 | 1-3/4″ | 12-3/4″ | BX-155 |
| 5-1/8″ | 5,000 | 14-3/4″ | 8 | 1-1/2″ | 10-3/4″ | R-44 |
| 7-1/16″ | 2,000 | 14″ | 12 | 1″ | 7-1/2″ | R-45 |
| 7-1/16″ | 3,000 | 15″ | 12 | 1-1/8″ | 8-1/2″ | R-45 |
| 7-1/16″ | 5,000 | 15-1/2″ | 12 | 1-3/8″ | 11-1/4″ | R-46 |
| 7-1/16″ | 10,000 | 18-7/8″ | 12 | 1-1/2″ | 11-3/4″ | BX-156 |
| 7-1/16″ | 15,000 | 19-7/8″ | 16 | 1-1/2″ | 13″ | BX-156 |
| 7-1/16″ | 20,000 | 24-13/16″ | 16 | 2″ | 17-3/4″ | BX-156 |
| 9″ | 2,000 | 16-1/2″ | 12 | 1-1/8″ | 8-1/2″ | R-49 |
| 9″ | 3,000 | 18-1/2″ | 12 | 1-3/8″ | 9-1/2″ | R-49 |
| 9″ | 5,000″ | 19″ | 12 | 1-5/8″ | 12-1/2″ | R-50 |
| 9″ | 10,000 | 21-3/4″ | 16 | 1-1/2″ | 13-1/4″ | BX-157 |
| 9″ | 15,000 | 25-1/2″ | 16 | 1-7/8″ | 16″ | BX-157 |
| 11″ | 2,000 | 20″ | 16 | 1-1/4″ | 9-1/4″ | R-53 |
| 11″ | 3,000 | 21-1/2″ | 16 | 1-3/8″ | 10″ | R-53 |
| 11″ | 5,000 | 23″ | 12 | 1-7/8″ | 14-1/4″ | R-54 |
| 11″ | 10,000 | 25-3/4″ | 16 | 1-3/4″ | 15-3/8″ | BX-158 |
| 11″ | 15,000 | 32″ | 20 | 2″ | 19-1/2″ | BX-158 |
| 13-5/8″ | 2,000 | 22″ | 20 | 1-1/4″ | 9-1/2″ | R-57 |
| 13-5/8″ | 3,000 | 24″ | 20 | 1-3/8″ | 10-3/4″ | R-57 |
| 13-5/8″ | 5,000 | 26-1/2″ | 16 | 1-5/8″ | 12-3/4″ | BX-160 |
| 13-5/8″ | 10,000 | 30-1/4″ | 20 | 1-7/8″ | 17-3/4″ | BX-159 |
| 13-5/8″ | 15,000 | 34-7/8″ | 20 | 2-1/4″ | 21″ | BX-159 |
| 16-3/4″ | 2,000 | 27″ | 20 | 1-1/2″ | 10-3/4″ | R-65 |
| 16-3/4″ | 3,000 | 27-3/4″ | 20 | 1-5/8″ | 12-1/4″ | R-66 |
| 16-3/4″ | 5,000 | 30-3/8″ | 16 | 1-78″ | 14-3/4″ | BX-162 |
| 16-3/4″ | 10,000 | 34-5/16″ | 24 | 1-7/8″ | 17-3/4″ | BX-162 |
| 18-3/4″ | 5,000 | 35-5/8″ | 20 | 2″ | 18″ | BX-163 |
| 16-3/4″ | 10,000 | 40-15/16″ | 24 | 2-1/4″ | 23″ | BX-164 |
| 20-3/4″ | 3,000 | 33-3/4″ | 20 | 2″ | 15-1/4″ | R-74 |
| 21-1/4″ | 2,000 | 32″ | 24 | 1-5/8″ | 12-1/2″ | R-73 |
| 21-1/4″ | 5,000 | 39″ | 24 | 2″ | 19″ | BX-165 |
| 21-1/4″ | 10,000 | 45″ | 24 | 2-1/2″ | 24-3/4″ | BX-166 |
| 26-3/4″ | 2,000 | 41″ | 20 | 1-3/4″ | 14-1/4″ | BX-167 |
| 21-1/4″ | 3,000 | 43-3/8″ | 24 | 2″ | 17-1/2″ | BX-168 |
API 6A Weld Neck Flanges Dimensions:
API 6A – 6B 13.8 MPA (2000 PSI) Weld Neck Flanges Dimensions
API 6A – 6B 20.7 MPA (3000 PSI) Weld Neck Flanges Dimensions
| Size | B | OD | C (MAX.) | K | P | E | T | Q | X | BC | N | H | LN | HL | JL | Ring Number (R or RX) |
| 2 1/16″ | 53.2 | 215 | 3 | 124 | 95.25 | 7.9 | 46.1 | 38.1 | 104.8 | 165.1 | 8 | 26 | 109.6 | 60.3 | 50 | 24 |
| 2 9/16″ | 65.9 | 245 | 3 | 137 | 108 | 7.9 | 49.3 | 41.3 | 123.8 | 190.5 | 8 | 29 | 112.7 | 73 | 59.7 | 27 |
| 3 1/8″ | 81.8 | 240 | 3 | 156 | 123.8 | 7.9 | 46.1 | 38.1 | 127 | 190.5 | 8 | 26 | 109.5 | 88.9 | 74.4 | 31 |
| 4 1/16″ | 108.7 | 290 | 3 | 181 | 149.2 | 7.9 | 52.4 | 44.4 | 158.8 | 235 | 8 | 32 | 122.2 | 114.3 | 98 | 37 |
| 5 1/8″ | 131 | 350 | 3 | 216 | 181 | 7.9 | 58.8 | 50.8 | 190.5 | 279.4 | 8 | 35 | 134.9 | 141.3 | 122.9 | 41 |
| 7 1/16″ | 181.8 | 380 | 6 | 241 | 211.2 | 7.9 | 63.5 | 55.6 | 235 | 317.5 | 12 | 32 | 147.6 | 168.3 | 147.1 | 45 |
| 9″ | 229.4 | 470 | 6 | 308 | 269.9 | 7.9 | 71.5 | 63.5 | 298.5 | 393.7 | 12 | 39 | 169.9 | 219.1 | 189.7 | 49 |
| 11″ | 280.2 | 545 | 6 | 362 | 323.9 | 7.9 | 77.8 | 69.9 | 368.3 | 469.9 | 16 | 39 | 192.1 | 273 | 237.2 | 53 |
| 13 5/8″ | 346.9 | 610 | 6 | 419 | 381 | 7.9 | 87.4 | 79.4 | 419.1 | 533.4 | 20 | 39 | – | – | – | 57 |
| 16 3/4″ | 426.2 | 705 | 6 | 524 | 469.9 | 11.2 | 100.1 | 88.9 | 508 | 616 | 20 | 45 | – | – | – | 66 |
| 20 3/4″ | 527.8 | 855 | 6 | 648 | 584.2 | 12.7 | 120.7 | 108 | 622.3 | 749.3 | 20 | 54 | – | – | – | 74 |
API 6A – 6B 34.5 MPA (5000 PSI) Weld Neck Flanges Dimensions
API 6A – 6BX 69.0 MPA (10000 PSI) Weld Neck Flanges Dimensions
API 6A – 6BX 103.5 MPA (15000 PSI) Weld Neck Flanges Dimensions
API 6A – 6BX 138.0 MPA (20000 PSI) Weld Neck Flanges Dimensions
⬇️ Download API 6A Flanges 6B 5000 PSI Weld Neck Flange and Blind Flange dimension Now (PDF)
