Understanding your choice of API flanges options
There are several factors to consider when choosing API flanges, including the type of application, pressure rating, and compatibility with other components. Type of application: Different API flanges are designed for different applications, such as high pressure, high temperature, or corrosive environments. Selecting the right flange for the specific application ensures the safety and effectiveness of the system. Pressure rating: API flanges are rated for different maximum pressures, so it is important to choose a flange that can handle the expected pressure in the system. Material: API flanges are made from a variety of materials, including carbon steel, stainless steel, and other alloys. The choice of material will depend on the specific requirements of the application, including the temperature and corrosive environment. Connection type: API flanges are available in different connection types, such as weld neck, slip-on, and threaded. The choice of connection type will depend on the specific requirements of the application, including the type of pipe and the type of gasket used. Size: API flanges are available in different sizes to match the size of the pipe. It is important to choose a flange with a size that is equal to or greater than the size of the pipe to ensure a proper fit and seal. Compatibility: API flanges are available in different sizes and connection types, so it is important to ensure that the chosen flange is compatible with other components in the system. By understanding these factors and carefully selecting the appropriate API flange, you can ensure the safety and efficiency of your system.
What is ASTM and API?
ASTM and API are organizations that develop standards for a variety of industries. ASTM International, formerly known as the American Society for Testing and Materials, is an organization that develops and publishes technical standards for a wide range of materials, products, systems, and services. API, or the American Petroleum Institute, is a trade organization that represents the oil and natural gas industry in the United States. They develop standards for the design, construction, and operation of equipment and facilities used in the oil and gas industry.
What are API flanges?
API flanges are flanges that are designed to meet the specifications of the American Petroleum Institute (API). These flanges are commonly used in the oil and gas industry for connecting pipes and other equipment. API flanges come in a variety of sizes and pressure ratings, and are made from materials such as carbon steel, stainless steel, and other alloys. They are typically used in high-pressure and high-temperature applications, and are known for their durability and reliability.
What are API 6A flanges?
API 6A flanges are a type of flange used in the oil and gas industry. They are designed to meet the American Petroleum Institute’s (API) specifications for high-pressure and high-temperature applications. These flanges typically have a pressure rating of 10,000 psi or higher, and are available in a range of sizes and materials, including carbon steel, stainless steel, and alloy steel. API 6A flanges are commonly used in oil and gas drilling, production, and processing operations.
What is the difference between API 6A and 16A?
API 6A and API 16A are both industry standards for the design and construction of equipment and components used in the oil and gas industry. API 6A specifies requirements for wellhead and Christmas tree equipment, while API 16A specifies requirements for drilling and production-related equipment, such as blowout preventers and well control equipment. The main difference between the two standards is the type of equipment they cover. API 6A covers wellhead and Christmas tree equipment, which are used to control the flow of oil and gas from the wellbore to the surface. This equipment is critical for maintaining the integrity of the wellbore and preventing the release of hydrocarbons. API 16A, on the other hand, covers drilling and production-related equipment, such as blowout preventers, well control systems, and drilling spools. This equipment is used to control the flow of oil and gas during drilling and production operations, and is essential for ensuring the safety of personnel and the environment. The main difference between API 6A and API 16A is the type of equipment covered by each standard. API 6A covers wellhead and Christmas tree equipment, while API 16A covers drilling and production-related equipment.
What is difference between API and ASME?
API and ASME are two different organizations that have nothing to do with each other. API stands for the American Petroleum Institute, which is a trade association that represents the oil and natural gas industry in the United States. It develops and publishes standards for the design and construction of equipment and facilities used in the oil and gas industry. ASME, on the other hand, stands for the American Society of Mechanical Engineers, which is a professional organization that focuses on the field of mechanical engineering. It offers a wide range of services, including professional development, certification, and networking opportunities for mechanical engineers. It also publishes technical standards and codes that are used in various industries, including the oil and gas industry. API is an industry association that focuses on the oil and gas industry, while ASME is a professional organization for mechanical engineers that publishes technical standards and codes used in various industries.
Why is bolting together an ASME ANSI flange to an API flange not recommended?
Bolting together an ASME ANSI flange to an API flange is not recommended because the two flanges are not designed to be used together. ASME and API flanges have different dimensions, bolt patterns, and pressure ratings, so using them together could compromise the integrity of the connection and potentially cause leaks or other problems. It is always best to use flanges that are designed to be used together, as specified by the relevant industry standards.
What are the different types of API flanges?
API flanges are pipe flanges that are manufactured according to specifications from the American Petroleum Institute (API). There are several different types of API flanges, including welding neck flanges, slip-on flanges, threaded flanges, and lap joint flanges. These flanges are used in a variety of applications, such as connecting pipes in oil and gas systems, and are designed to be strong and durable. The type of flange used in a particular application will depend on the specific requirements of the system and the type of connection that is needed.
Types of API Flanges
These are the most common type of API flange, and they are designed to be welded to the end of a pipe. They have a long, tapered neck that is welded to the pipe, providing a strong and leak-proof connection.
These flanges are designed to “slip” over the end of a pipe and then be welded in place. They are easy to install and have a slightly lower pressure rating than weld neck flanges.
These flanges have threads on their inner and outer surfaces, allowing them to be screwed onto the end of a pipe. They are often used in low-pressure applications, and they can be easily removed and replaced.
These flanges are similar to slip-on flanges, but they have a socket-like depression on their inner surface that allows them to be “welded” to the end of a pipe using a fillet weld.
These flanges are designed to be used in conjunction with a lap joint stub end. The flange has a collar that fits over the stub end, and the two are then welded together to form a strong and leak-proof connection.
These flanges are designed to be used in applications where the pipe ends need to be sealed off. They do not have any openings and are used to block the flow of fluids or gases.
These flanges are used in applications where the flow of fluids or gases needs to be measured. They have a small opening, or orifice, that allows the flow to be measured accurately.
These flanges are made up of two separate pieces that are joined together. They are often used in applications where the flow of fluids or gases needs to be diverted or controlled.
These flanges have a ring-shaped groove on the inside of the flange that allows them to create a strong seal when used with a matching ring. They are often used in high-pressure applications.
These flanges are specifically designed to be used with orifice meters, which are used to measure the flow of fluids in piping systems.
These flanges are used when the diameter of the pipe changes, allowing for a smooth transition between different sizes of pipes. Each type of API flange has its own unique characteristics and benefits, and the right type of flange to use will depend on the specific application and the requirements of the project.
6BX and 6B Flanges
6BX and 6B Flanges (welding neck flanges, blind flanges, target flanges and test flanges) are fully conformed to API 6A and made of modern alloy steel via advanced manufacturing techniques. They are robust and high-cost performance.
6B flanges are of the ring joint type and are not designed for face-to-face make-up. The connection make-up bolting force reacts on the metallic ring gasket.
6BX flanges are of the ring joint type and designed with a raised face. Depending on the tolerances, the connection make-up bolting force may react on the raised face of the flange when the gasket has been properly seated. This support prevents damage to the flange or gasket from excessive bolt torque.
6BX and 6B Welding Neck Flanges
6B weld neck flanges conforming to Table 36, Table 37 and Table 38 of API 6A (19th Edition) are available.
6BX weld neck flanges conforming to Table 42 or Table 43 of API 6A (19th Edition) are available.
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6B welding neck flange | 6BX welding neck flange |
6BX and 6B Blind Flanges
6B blind flanges conforming to Table 36, Table 37 and Table 38 of API 6A (19th Edition) are available.
6BX blind flanges conforming to Table 46 of API 6A (19th Edition) are available.
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6B blind flange | 6BX blind flange | 6BX blind flange with fluid cushion counterbore |
6BX Target Flanges, Lead Filled
Target Flange: a special configuration of blind flange used downstream, facing upstream, to cushion and reduce the erosive affect of high velocity abrasive fluid. This flange has a counter bore filled with lead as illustrated below.
Target Flanges conforming to Table 44 and Table 45 of API 6A are available.
6BX and 6B Test Flanges
6B test flanges conforming to Table 36, Table 37 and Table 38 of API 6A (19th Edition) are available.
6BX test flanges conforming to Table 44 and Table 45 of API 6A are available.
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6B test flange | 6BX test flange |
Material of API flanges
API flanges can be made from a variety of materials, including carbon steel, stainless steel, alloy steel, and other specialty materials. The type of material used will depend on the specific application and the operating conditions of the flange. Carbon steel is often used for general-purpose applications, while stainless steel is used for more corrosive environments. Alloy steel is used for high-temperature and high-pressure applications. Specialty materials such as Inconel and Monel are used for extreme conditions and specialized applications.
- Stainless Steel API Flanges: ASTM A 182, A 240 F 304, 304L, 304H, 316, 316L, 316Ti, 310, 310S, 321, 321H, 317, 347, 347H, 904L
- Duplex & Super Duplex Steel API Flanges : ASTM / ASME A/SA 182 F 44, F 45, F51, F 53, F 55, F 60, F 61
- Carbon Steel API Flanges: ASTM / ASME A/SA 105 ASTM / ASME A 350 , ASTM A 181 LF 2 / A516 Gr.70 A36, A694 F42, F46, F52, F60, F65, F706
- Low Temperature Carbon Steel API Flanges: ASTM A350, LF2, LF3
- Alloy Steel API Flanges: ASTM / ASME A/SA 182 & A 387 F1, F5, F9, F11, F12, F22, F91
- Copper Alloy Steel API Flanges: ASTM SB 61 , SB62 , SB151 , SB152 UNS No. C 70600 (Cu-Ni 90/10), C 71500 (Cu-Ni 70/30), UNS No. C 10100, 10200, 10300, 10800, 12000, 12200
- Nickel Alloy API Flanges: ASTM SB564, SB160, SB472, SB162 Nickel 200 (UNS No. N02200), Nickel 201 (UNS No. N02201), Monel 400 (UNS No. N04400), Monel 500 (UNS No. N05500), Inconel 800 (UNS No. N08800), Inconel 825 (UNS No. N08825), Inconel 600 (UNS No. N06600), Inconel 625 (UNS No. N06625), Inconel 601 (UNS No. N06601), Hastelloy C 276 (UNS No. N10276), Alloy 20 (UNS No. N08020)
Size of API flanges
API flanges come in a variety of sizes, depending on the specific application they are intended for. The size of an API flange is determined by the diameter of the pipe it is being used with, as well as the pressure rating and flange type. Some common sizes of API flanges include 2″, 4″, 6″, 8″, 10″, and 12″. It’s important to choose the right size of flange for your application to ensure a proper fit and adequate pressure rating.
Dimension of API Flange
The dimensions of API flanges vary depending on the type and size of the flange. Below are some common dimensions for different types of flanges:
Dimensions of Welding Neck Flanges and Blind Flanges as per API 6A Type 6BX 20000 psi Flange
Dimensions of Type 6BX flanges for 20000 psi (138 MPa) rated working pressure.
Type 6BX flanges are of the ring joint type and designed with a raised face. Depending on the tolerances, the connection make-up bolting force may react on the raised face of the flange when the gasket has been properly seated. This prevents damage to the flange or gasket from excessive bolt torque.
All dimensions are in “mm” unless noted otherwise. Only flange sizes are in imperial units.
Size-(inches) | B | OD | C | E1 | Q (max) | G | K | T | J1 | J2 | J3 | J4 | R | BC | N | H | Ring Number BX |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 13/16″ | 46.8 | 255 | 3 | – | 5.56 | 77.77 | 117 | 63.5 | 133.4 | 109.5 | 49.2 | – | 10 | 203.20 | 8 | 29 | 151 |
2 1/16″ | 53.2 | 285 | 3 | – | 5.95 | 86.23 | 132 | 71.5 | 154.0 | 127.0 | 52.4 | – | 10 | 230.20 | 8 | 32 | 152 |
2 9/16″ | 65.9 | 325 | 3 | – | 6.75 | 102.77 | 151 | 79.4 | 173.0 | 144.5 | 58.7 | – | 10 | 261.90 | 8 | 35 | 153 |
3 1/16″ | 78.6 | 355 | 3 | – | 7.54 | 119.00 | 171 | 85.8 | 192.1 | 160.3 | 63.5 | – | 10 | 287.30 | 8 | 39 | 154 |
4 1/16″ | 104.0 | 445 | 3 | – | 8.33 | 150.62 | 219 | 106.4 | 242.9 | 206.4 | 73.0 | – | 10 | 357.20 | 8 | 48 | 155 |
7 1/16″ | 180.2 | 655 | 6 | 11.1 | 11.11 | 241.83 | 352 | 165.1 | 385.8 | 338.1 | 96.8 | 7.9 | 16 | 554 | 16 | 54 | 156 |
9″ | 229.4 | 805 | 6 | 12.7 | 12.7 | 299.06 | 441 | 204.8 | 481.0 | 428.6 | 107.9 | 6.4 | 25 | 685.80 | 16 | 67 | 157 |
11″ | 280.2 | 885 | 6 | 14.3 | 14.29 | 357.23 | 505 | 223.9 | 566.7 | 508.0 | 103.2 | 12.7 | 25 | 749.30 | 16 | 74 | 158 |
13 5/8″ | 346.9 | 1160 | 6 | 15.9 | 15.88 | 432.64 | 614 | 292.1 | 693.7 | 628.6 | 133.3 | 14.2 | 25 | 1016 | 20 | 80 | 159 |
Dimensions of Welding Neck Flanges and Blind Flanges as per API 6A Type 6BX 15000 psi Flange
Dimensions of Type 6BX flanges for 15000 psi (103.5 MPa) rated working pressure.
Type 6BX flanges are of the ring joint type and designed with a raised face. Depending on the tolerances, the connection make-up bolting force may react on the raised face of the flange when the gasket has been properly seated. This prevents damage to the flange or gasket from excessive bolt torque.
All dimensions are in “mm” unless noted otherwise. Only flange sizes are in imperial units.
Size-(inches) | B | OD | C | E1 | Q (max) | G | K | T | J1 | J2 | J3 | J4 | R | BC | N | H | Ring Number BX |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 13/16″ | 46.8 | 210 | 3 | – | 5.56 | 77.77 | 106 | 45.3 | 97.6 | 71.4 | 47.6 | – | 10 | 160.3 | 8 | 26 | 151 |
2 1/16″ | 53.2 | 220 | 3 | – | 5.95 | 86.23 | 114 | 50.8 | 111.1 | 82.5 | 54.0 | – | 10 | 174.60 | 8 | 26 | 152 |
2 9/16″ | 65.9 | 255 | 3 | – | 6.75 | 102.77 | 133 | 57.2 | 128.6 | 100.0 | 57.1 | – | 10 | 200.00 | 8 | 29 | 153 |
3 1/16″ | 78.6 | 290 | 3 | – | 7.54 | 119.00 | 154 | 64.3 | 154.0 | 122.2 | 63.5 | – | 10 | 230.20 | 8 | 32 | 154 |
4 1/16″ | 104.0 | 360 | 3 | – | 8.33 | 150.62 | 194 | 78.6 | 195.3 | 158.7 | 73.0 | – | 10 | 290.50 | 8 | 39 | 155 |
5 1/8″ | 131.0 | 420 | 3 | 9.5 | 9.53 | 176.66 | 225 | 98.5 | 244.5 | 200.0 | 81.8 | 6.4 | 16 | 342.90 | 12 | 42 | 169 |
7 1/16″ | 180.2 | 505 | 6 | 11.1 | 11.11 | 241.83 | 305 | 119.1 | 325.4 | 276.2 | 92.1 | 7.9 | 16 | 428.60 | 16 | 42 | 156 |
9″ | 229.4 | 650 | 6 | 12.7 | 12.70 | 299.06 | 381 | 146.1 | 431.8 | 349.2 | 123.8 | 14.2 | 16 | 552.40 | 16 | 51 | 157 |
11″ | 280.2 | 815 | 6 | 14.3 | 14.29 | 357.23 | 454 | 187.4 | 584.2 | 427.0 | 235.7 | 12.7 | 16 | 711.20 | 20 | 54 | 158 |
13 5/8″ | 346.9 | 885 | 6 | 15.9 | 15.88 | 432.64 | 541 | 204.8 | 595.3 | 528.6 | 114.3 | 17.5 | 25 | 771.50 | 20 | 61 | 159 |
18 3/4″ | 477.0 | 1160 | 6 | 18.3 | 18.26 | 577.90 | 722 | 255.6 | 812.8 | 730.2 | 155.6 | 35.1 | 25 | 1016.00 | 20 | 80 | 164 |
Dimensions of Welding Neck Flanges and Blind Flanges as per API 6A Type 6BX 10000 psi Flange
Dimensions of Type 6BX flanges for 10000 psi (69 MPa) rated working pressure.
Type 6BX flanges are of the ring joint type and designed with a raised face. Depending on the tolerances, the connection make-up bolting force may react on the raised face of the flange when the gasket has been properly seated. This prevents damage to the flange or gasket from excessive bolt torque.
All dimensions are in “mm” unless noted otherwise. Only flange sizes are in imperial units.
Size-(inches) | B | OD | C | E1 | Q (max) | G | K | T | J1 | J2 | J3 | J4 | R | BC | N | H | Ring Number BX |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 13/16″ | 46.8 | 185 | 3 | – | 5.56 | 77.77 | 105 | 42.1 | 88.9 | 65.1 | 48.5 | – | 10 | 146.10 | 8 | 23 | 151 |
2 1/16″ | 53.2 | 200 | 3 | – | 5.95 | 86.23 | 1011 | 44.1 | 100.0 | 74.7 | 51.6 | – | 10 | 158.80 | 8 | 23 | 152 |
2 9/16″ | 65.9 | 230 | 3 | – | 6.75 | 102.77 | 132 | 51.2 | 120.7 | 92.1 | 57.2 | – | 10 | 184.20 | 8 | 26 | 153 |
3 1/16″ | 78.6 | 270 | 3 | – | 7.54 | 119.00 | 152 | 58.4 | 142.1 | 110.2 | 63.5 | – | 10 | 215.90 | 8 | 29 | 154 |
4 1/16″ | 104.0 | 315 | 3 | – | 8.33 | 150.62 | 185 | 70.3 | 182.6 | 146.1 | 73.1 | – | 10 | 258.80 | 8 | 32 | 155 |
5 1/8″ | 131.0 | 360 | 3 | 9.5 | 9.53 | 176.66 | 221 | 79.4 | 223.8 | 182.6 | 81.0 | 6.4 | 10 | 300 | 12 | 32 | 169 |
7 1/16″ | 180.2 | 480 | 6 | 11.1 | 11.11 | 241.83 | 302 | 103.2 | 301.6 | 254 | 95.3 | 9.7 | 16 | 403.20 | 12 | 42 | 156 |
9″ | 229.4 | 550 | 6 | 12.7 | 12.70 | 299.06 | 359 | 123.9 | 374.7 | 327.1 | 93.7 | 9.7 | 16 | 476.30 | 16 | 42 | 157 |
11″ | 280.2 | 655 | 6 | 14.3 | 14.29 | 357.23 | 429 | 141.3 | 450.9 | 400.1 | 103.2 | 14.2 | 16 | 565.20 | 16 | 48 | 158 |
13 5/8″ | 346.9 | 770 | 6 | 15.9 | 15.88 | 432.64 | 518 | 168.3 | 552.5 | 495.3 | 114.3 | 17.5 | 16 | 673.10 | 20 | 51 | 159 |
16 3/4″ | 426.2 | 870 | 6 | 8.3 | 8.33 | 478.33 | 576 | 168.3 | 655.6 | 601.7 | 76.2 | 30.2 | 19 | 776.30 | 24 | 51 | 162 |
18 3/4″ | 477.0 | 1040 | 6 | 18.3 | 18.26 | 577.90 | 697 | 223.1 | 752.5 | 674.7 | 155.6 | 25.4 | 16 | 925.50 | 24 | 61 | 164 |
21 1/4″ | 540.5 | 1145 | 6 | 19.1 | 19.05 | 647.88 | 781 | 241.3 | 847.7 | 762.0 | 165.1 | 31.8 | 21 | 1022.40 | 24 | 67 | 166 |
Dimensions of Welding Neck Flanges and Blind Flanges as per API 6A Type 6BX 5000 psi Flange
Dimensions of Type 6BX flanges for 5000 psi (34.5 MPa) rated working pressure.
Type 6BX flanges are of the ring joint type and designed with a raised face. Depending on the tolerances, the connection make-up bolting force may react on the raised face of the flange when the gasket has been properly seated. This prevents damage to the flange or gasket from excessive bolt torque.
All dimensions are in “mm” unless noted otherwise. Only flange sizes are in imperial units.
Size | B | OD | C | E1 | Q (max) | G | K | T | J1 | J2 | J3 | J4 | R | BC | N | H | Ring Number BX |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
13 5/8″ | 346.9 | 675 | 6 | 14.3 | 14.29 | 408.00 | 457 | 112.8 | 481.0 | 423.9 | 114.3 | 23.9 | 16 | 590.60 | 16 | 45 | 160 |
16 3/4″ | 426.2 | 770 | 6 | 8.3 | 8.33 | 478.33 | 535 | 130.2 | 555.6 | 527.1 | 76.2 | 17.5 | 19 | 676.30 | 16 | 51 | 162 |
18 3/4″ | 477.0 | 905 | 6 | 18.3 | 18.26 | 563.50 | 627 | 165.9 | 674.7 | 598.5 | 152.4 | 19.1 | 16 | 803.30 | 20 | 54 | 163 |
21 1/4″ | 540.5 | 990 | 6 | 19.1 | 19.05 | 632.56 | 702 | 181.0 | 758.8 | 679.5 | 165.1 | 22.4 | 18 | 885.80 | 24 | 54 | 165 |
Dimensions of Welding Neck Flanges and Blind Flanges as per API 6A Type 6BX 3000 psi Flange
Dimensions of Type 6BX flanges for 3000 psi (20.7 MPa) rated working pressure.
Type 6BX flanges are of the ring joint type and designed with a raised face. Depending on the tolerances, the connection make-up bolting force may react on the raised face of the flange when the gasket has been properly seated. This prevents damage to the flange or gasket from excessive bolt torque.
All dimensions are in “mm” unless noted otherwise. Only flange sizes are in imperial units.
Size-(inches) | B | OD | C | E1 | Q (max) | G | K | T | J1 | J2 | J3 | J4 | R | BC | N | H | Ring Number BX |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
26 3/4″ | 680.2 | 1100 | 6 | 21.4 | 21.43 | 774.22 | 832 | 161.2 | 870 | 776.3 | 185.7 | 0 | 16 | 1000.10 | 24 | 54 | 168 |
30″ | 762.8 | 1185 | 6 | 23 | 22.62 | 862.30 | 922 | 167.1 | 970 | 871.1 | 196.9 | 12.7 | 16 | 1090.60 | 32 | 51 | 303 |
Dimensions of Welding Neck Flanges and Blind Flanges as per API 6A Type 6BX 2000 psi Flange
Dimensions of Type 6BX flanges for 2000 psi (13.8 MPa) rated working pressure.
Type 6BX flanges are of the ring joint type and designed with a raised face. Depending on the tolerances, the connection make-up bolting force may react on the raised face of the flange when the gasket has been properly seated. This prevents damage to the flange or gasket from excessive bolt torque.
All dimensions are in “mm” unless noted otherwise. Only flange sizes are in imperial units.
Size-(inches) | B | OD | C | E1 | Q (max) | G | K | T | J1 | J2 | J3 | J4 | R | BC | N | H | Ring Number BX |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
26 3/4″ | 680.2 | 1040 | 6 | 21.4 | 21.43 | 768.33 | 805 | 126.3 | 835.8 | 743 | 185.7 | 9.7 | 16 | 952.5 | 20 | 48 | 167 |
30″ | 762.8 | 1120 | 6 | 23 | 22.62 | 862.30 | 908 | 134.2 | 931.9 | 833 | 196.9 | 17.5 | 16 | 1039.80 | 32 | 45 | 303 |
Dimensions of Welding Neck Flanges and Blind Flanges as per API 6A Type 6B 5000 psi Flange
Dimensions of Type 6B flanges for 5000 psi (34.5 MPa) rated working pressure.
Type 6B flanges are of the ring joint type and are not designed for face-to-face make-up. The connection make-up bolting force reacts on the metallic ring gasket.
All dimensions are in “mm” unless noted otherwise. Only flange sizes are in imperial units.
Size | B1 | O | C | K | P | E | X | BC | N | H | Y | A | B2 | Ring Number R or RX |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2 1/16″ | 53.2 | 215 | 46.1 | 124 | 95.25 | 7.9 | 104.8 | 165.1 | 8 | 26 | 109.6 | 60.3 | 43.7 | 24 |
2 9/16″ | 65.9 | 245 | 49.3 | 137 | 107.95 | 7.9 | 123.8 | 190.5 | 8 | 29 | 112.7 | 73.0 | 54.9 | 27 |
3 1/8″ | 81.8 | 265 | 55.6 | 168 | 136.53 | 7.9 | 133.3 | 203.2 | 8 | 32 | 125.4 | 88.9 | 67.5 | 35 |
4 1/16″ | 108.7 | 310 | 62.0 | 194 | 161.93 | 7.9 | 161.9 | 241.3 | 8 | 35 | 131.8 | 114.3 | 88.1 | 39 |
5 1/8″ | 131.0 | 375 | 81.0 | 229 | 193.68 | 7.9 | 196.8 | 292.1 | 8 | 42 | 163.5 | 141.3 | 110.3 | 44 |
7 1/16″ | 181.0 | 395 | 92.1 | 248 | 211.15 | 9.7 | 228.6 | 317.5 | 12 | 39 | 181 | 168.3 | 132.6 | 46 |
9″ | 229.4 | 485 | 103.2 | 318 | 269.88 | 11.2 | 292.1 | 393.7 | 12 | 45 | 223.8 | 219.1 | 173.8 | 50 |
11″ | 280.2 | 585 | 119.1 | 371 | 323.85 | 11.2 | 368.3 | 482.6 | 12 | 51 | 265.1 | 273 | 216.7 | 54 |
Dimensions of Welding Neck Flanges and Blind Flanges as per API 6A Type 6B 3000 psi Flange
Dimensions of Type 6B flanges for 3000 psi (20.7 MPa) rated working pressure.
Type 6B flanges are of the ring joint type and are not designed for face-to-face make-up. The connection make-up bolting force reacts on the metallic ring gasket.
All dimensions are in “mm” unless noted otherwise. Only flange sizes are in imperial units.
Size | B1 | O | C | K | P | E | X | BC | N | H | Y | A | B2 | Ring Number R or RX |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2 1/16″ | 53.2 | 215 | 46.1 | 124 | 95.25 | 7.9 | 104.8 | 165.1 | 8 | 26 | 109.6 | 60.3 | 50.0 | 24 |
2 9/16″ | 65.9 | 245 | 49.3 | 137 | 107.95 | 7.9 | 123.8 | 190.5 | 8 | 29 | 112.7 | 73.0 | 59.7 | 27 |
3 1/8″ | 81.8 | 240 | 46.1 | 156 | 123.83 | 7.9 | 127.0 | 190.5 | 8 | 26 | 109.5 | 88.9 | 74.4 | 31 |
4 1/16″ | 108.7 | 290 | 52.4 | 181 | 149.23 | 7.9 | 158.8 | 235.0 | 8 | 32 | 122.2 | 114.3 | 98.0 | 37 |
5 1/8″ | 131.0 | 350 | 58.8 | 216 | 180.98 | 7.9 | 190.5 | 279.4 | 8 | 35 | 134.9 | 141.3 | 122.9 | 41 |
7 1/16″ | 181.0 | 380 | 63.5 | 241 | 211.15 | 7.9 | 235 | 317.5 | 12 | 32 | 147.6 | 168.3 | 147.1 | 45 |
9″ | 229.4 | 470 | 71.5 | 308 | 269.88 | 7.9 | 298.5 | 393.7 | 12 | 39 | 169.9 | 219.1 | 189.7 | 49 |
11″ | 280.2 | 545 | 77.8 | 362 | 323.85 | 7.9 | 368.3 | 469.9 | 16 | 39 | 192.1 | 273 | 237.2 | 53 |
13 5/8 “ | 346.9 | 610 | 87.4 | 419 | 381.00 | 7.9 | 419.1 | 533.4 | 20 | 39 | – | – | – | 57 |
16 3/4″ | 426.2 | 705 | 100.1 | 524 | 469.90 | 11.2 | 508.0 | 616.0 | 20 | 45 | – | – | – | 66 |
20 3/4″ | 527.8 | 855 | 120.7 | 648 | 584.20 | 12.7 | 622.9 | 749.3 | 20 | 54 | – | – | – | 74 |
Dimensions of Welding Neck Flanges and Blind Flanges as per API 6A Type 6B 2000 psi Flange
Dimensions of Type 6B flanges for 2000 psi (13.8 MPa) rated working pressure.
Type 6B flanges are of the ring joint type and are not designed for face-to-face make-up. The connection make-up bolting force reacts on the metallic ring gasket.
All dimensions are in “mm” unless noted otherwise. Only flange sizes are in imperial units.
Size | B1 | O | C | K | P | E | X | BC | N | H | Y | A | B2 | Ring Number R or RX |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2 1/16″ | 53.2 | 165 | 33.4 | 108 | 82.55 | 7.9 | 84 | 127 | 8 | 20 | 81 | 60.3 | 53.3 | 23 |
2 9/16″ | 65.9 | 190 | 36.6 | 127 | 101.60 | 7.9 | 100 | 149.2 | 8 | 23 | 88 | 73.0 | 63.5 | 26 |
3 1/8″ | 81.8 | 210 | 39.7 | 146 | 123.83 | 7.9 | 117 | 168.3 | 8 | 23 | 91 | 88.9 | 78.7 | 31 |
4 1/16″ | 108.7 | 275 | 46.1 | 175 | 149.23 | 7.9 | 152 | 215.9 | 8 | 26 | 110 | 114.3 | 103.1 | 37 |
5 1/8″ | 131.0 | 330 | 52.4 | 210 | 180.98 | 7.9 | 189 | 266.7 | 8 | 29 | 122 | 141.3 | 122.9 | 41 |
7 1/16″ | 181.0 | 355 | 55.6 | 241 | 211.15 | 7.9 | 222 | 292.1 | 12 | 29 | 126 | 168.3 | 147.1 | 45 |
9″ | 229.4 | 420 | 63.5 | 302 | 269.88 | 7.9 | 273 | 349.3 | 12 | 32 | 141 | 219.1 | 199.1 | 49 |
11″ | 280.2 | 510 | 71.5 | 356 | 323.85 | 7.9 | 343 | 431.8 | 16 | 35 | 160 | 273.0 | 248.4 | 53 |
13 5/8 “ | 346.9 | 560 | 74.7 | 413 | 381.00 | 7.9 | 400 | 489 | 20 | 35 | – | – | – | 57 |
16 3/4″ | 426.2 | 685 | 84.2 | 508 | 469.90 | 7.9 | 495 | 603.2 | 20 | 42 | – | – | – | 65 |
21 1/4″ | 540.5 | 815 | 98.5 | 635 | 584.20 | 9.7 | 610 | 723.9 | 24 | 45 | – | – | – | 73 |
Flange Section Integral


1. Nominal Size and Bore of Flange | 2. Max Bore | 3. Outside Dia Flange | 4. Tolerance (3) |
5. Max Chamfer | 6. Dia Raised Face | 7. Total Thk Flange | 8. Basic Thk Flange |
9. Dia Hub | 10. Dia Bolt Circle | 11. Number of Bolt Holes | 12. Dia of Bolts |
13. Dia Bolt Holes | 14. Bolt Hole Tolerance (Min -0.02) | 15. Length Stud Bolts | 16. Hub Length Threaded Line Pipe Flange |
17. Hub Length Threaded Casing Flange | 18. Hub Length Welding Neck Line Pipe Flange ±0.06 | 19. Neck Dia Welding Neck Line Pipe Flange | 20. Tolerance (19) |
21. Max. Bore Weld Neck Flange | 22. Ring Number R or RX |
Packing of API flanges
API flanges are packed in sturdy wooden or cardboard boxes to protect them from damage during transportation and storage. The flanges are typically wrapped in protective padding and secured with bubble wrap or foam sheets to prevent any scratches or dents on the surface. The boxes are labeled with the flange size, material, and other relevant information for easy identification and traceability. Additionally, the boxes are sealed with strong adhesive tapes to prevent tampering and ensure the flanges are delivered in pristine condition.
Surface Treatment of API flanges
API flanges are used in a variety of industries, including the oil and gas industry, to connect pipes, valves, and other equipment. Surface treatment of these flanges is important to ensure they can withstand the challenging environments in which they are used and to improve their performance. One common surface treatment for API flanges is galvanization, which involves coating the flange with a layer of zinc to protect it from corrosion. This is often done by dipping the flange in a bath of molten zinc, which forms a protective layer over the surface of the flange. Another surface treatment option is electroplating, which involves applying a thin layer of another metal, such as nickel or chrome, over the surface of the flange using an electrical current. This can improve the corrosion resistance and wear resistance of the flange. Other surface treatments for API flanges include heat treating, painting, and coating with specialized materials such as PTFE or ceramics. The specific surface treatment used will depend on the specific application and requirements of the flange.
Usage of API flanges
API flanges are commonly used in the oil and gas industry for connecting pipes and other equipment in the production, transportation, and storage of oil and gas. These flanges are designed to meet the specifications of the American Petroleum Institute (API), which ensures their compatibility with other API-compliant equipment and provides a standardized means of connection. API flanges are typically used in high-pressure and high-temperature applications, and are available in a variety of sizes, materials, and pressure ratings to suit different operating conditions. Some common applications for API flanges include:
- Connecting pipes in oil and gas production facilities, such as wellheads, manifolds, and flow lines;
- Joining pipes and equipment in offshore drilling rigs and platforms;
- Attaching valves, pumps, and other flow control equipment to pipelines;
- Creating flanged connections in storage tanks and other pressure vessels;
- Joining pipes in pipelines for the transportation of oil and gas.
How to purchase the correct API flange? There are a few key factors to consider when purchasing an API flange.
Determine the type and size of the API flange needed for the specific application. API flanges come in various sizes and types, such as weld neck, blind, and threaded.
Consider the material of the flange, as API flanges are available in different materials such as carbon steel, stainless steel, and alloy steel. Choose the material that is most suitable for the application and operating conditions.
Check the compatibility of the flange with the other components in the system, such as the piping, gasket, and bolts. API flanges have standard dimensions and bolt hole patterns, but it is important to confirm that they will fit and work properly with the other components.
Consider the pressure and temperature ratings of the flange. API flanges are rated for different pressure and temperature ranges, so it is important to choose a flange that is suitable for the operating conditions of your equipment.
Consider the type of connection needed for the flange. API flanges are available in a variety of connection types, such as welding neck, slip-on, threaded, or socket-weld. Choose the connection type that is compatible with your equipment.
Research and compare different suppliers of API flanges to find the best price and quality.
Purchase the API flange from a reputable supplier that offers a warranty and quality assurance. It is also recommended to request a certificate of conformity to ensure the flange meets the required API standards and specifications.
Once you have chosen the correct API flange for your application, place an order with the supplier and ensure that it is delivered and installed correctly by a qualified professional.
How to select API flange manufacturer?
- Research potential manufacturers and their capabilities. This can be done through online searches, industry publications, and referrals from other companies or industry professionals.
- Consider the specific requirements and specifications of the project. Select manufacturers that have experience and expertise in manufacturing API flanges to these specifications.
- Review the manufacturer’s quality assurance and control processes. API flanges must meet strict quality standards, so it is important to choose a manufacturer with a proven track record of producing high-quality products.
- Consider the manufacturer’s customer service and support. Choose a manufacturer that provides prompt and reliable support, as well as technical assistance and guidance.
- Compare prices and delivery times. Select a manufacturer that offers competitive prices and can meet the project’s timeline.
- Request samples or prototypes from the manufacturer to test their products and ensure they meet your standards and requirements.
- Consider the manufacturer’s reputation and customer feedback. Select a manufacturer with a positive reputation and a history of satisfied customers.
Where to select flange manufacturer?
There are several places to select a flange manufacturer, including online directories, industry trade shows, and industry associations. Some examples include:
- Online directories such as Thomasnet, GlobalSpec, and MacRae’s Blue Book. These directories provide a comprehensive list of flange manufacturers and allow users to search by location, product type, and certifications.
- Industry trade shows such as Valve World Americas and the International Fluid Power Exposition. These shows provide an opportunity to see and compare products from different manufacturers and talk to their representatives.
- Industry associations such as the American Society of Mechanical Engineers (ASME) and the International Flange Manufacturers Association (IFMA). These organizations provide a list of certified manufacturers and can provide information on industry standards and best practices.
- Contact the flange manufacturer directly to inquire about their products, services, and pricing.
- It is also important to research and compare different manufacturers to ensure they have a good track record, a wide range of products, and the necessary certifications and quality standards.
Consider factors such as quality, price, delivery time, and customer service when selecting a flange manufacturer.