ANSI/ASMI B16.5 Long Weld Neck Flanges
Kaizen Steel Industries provides a variety of long weld flanges. These flanges are designed for high-pressure situations and are especially useful when a long, tapered hub is needed. It’s crucial to specify the pipe schedule when placing an order. These flanges are ideal for environments with extreme temperature changes and where there is a lot of handling and bending.
ASME B16.5 long weld neck flanges are easy to identify by their long tapered hub, which gradually transitions from the pipe or fitting’s wall thickness. This design is important for applications in extreme temperatures, providing reinforcement and durability.
For example, stainless steel long weld neck flanges can handle high pressure, very low, or high temperatures. The smooth transition from the flange thickness to the pipe wall is beneficial, especially for class 600 flanges, which need to withstand repeated bending due to line expansion or other forces.
Carbon steel long weld neck flanges are bored to match the inside diameter of the connected pipe or fitting, ensuring smooth flow and reducing turbulence and erosion at the joint. The ASME B16.5 long weld neck flanges offer excellent stress distribution through the tapered hub and can be easily tested for defects using radiography.
The ASME B16.5 standard for long weld neck flanges applies to flanges and flanged fittings made from materials like cast or forged materials. However, blind flanges and some reducing long weld neck flanges can be made from cast, forged, or plate materials. The standard also includes guidelines for dimensions related to bolting, gaskets, and flange joints.
Manufacturers of long weld neck flanges should use this ASME B16.5 standard along with other ASME standards, including the Boiler and Pressure Vessel Code and the B31 Piping Codes. For example, the ASME B31.3 Piping Guide states that for steel pipes used in steam applications above 250 psi or in water service above 100 psi with temperatures over 220°F, the pipe must be seamless and have a thickness of at least schedule 80 as per ASME B36.10.
Specification - ASME B16.5 Long Weld Neck Flange
| Size: | 1/2″NB TO 24″NB IN |
| Class: | 150 LBS, 300 LBS, 600 LBS, 900 LBS, 1500 LBS, 2500 LBS DIN Standard ND-6,10, 16, 25, 40 Etc. |
| Materials: | Monel : Grade: Monel 400, Monel K500, Monel R-405 Nickel : Grade: Nickel 200, Nickel 201 Inconel : Grade: Inconel 600, Inconel 601, Inconel 625, Inconel 718 Incoloy : Grade: Incoloy 800, Inconel 800H, 800HT Hastalloy : Grade: Hastalloy B2, Hastalloy B3, Hastalloy C22, Hastalloy C276, Hastalloy X Titanium : Grade: Gr1, Gr2, Gr3, Gr5, Gr7, Gr11 Stainless Steel : Grade: ASTM A182 F202, F304/304L/304H, F316/316L, F316H, F316TI, F310, F321, F904L Carbon Steel : Grade: ASTM A105/A105N, A350 LF1, LF2 CL1/CL2, LF3 CL1/CL2, A694 F42, F46, F48, F50, F52, F56, F60, F65, F70, A516.60, 65, 70 (Spectacle Blind Flange, Spacer Ring/Spade Flange), Steel RST37.2, C22.8 Duplex Steel: Grade: ASTM / ASME A/SA 182 UNS F44, F45, F51, F53, F55, F60, F61 Alloy Steel: Grade : ASTM A182 F1, F5, F9, F11, F22, F91 |
| Value Added Service: | CNC Machine, Customized Flanges |
| Coating/Surface Treatment: | Anti-rust Paint, Oil Black Paint, Yellow Transparent, Zinc Plated, Cold and Hot Dip Galvanized |
Types of Long Weld Neck Flanges
ASTM A105 socket weld tee
ASME B16.5 RTJ Long Weld Neck Flange
ANSI B16.5 Slip On Integral Flange
ASME B16.47 Series A Integral Pipe Flange
Long Weld Neck Flange Dimension
| Size | Flange | Barrel OD | Bolting | Nut | Stud Bolt | Weights | Length | |||||||||||||||||
| Nom | Bore LWN & E | Bore HB | OD | Thk. | RF of OD | LWN | HB | E | # of Holes | Hole Size | Bolt Circle | Stop Dia | Relief Dia | Relief Length | Size | RF Length | RTJ Length | LWN | HB | E | Base | |||
| B | B | O | T | R | D | D | D | C | NS | NR | NL | Base | Per 1″ | Base | Per 1″ | Base | Per 1″ | L | ||||||
| 1/2 | 0.5 | 0.55 | 3.5 | 0.44 | 1.38 | 1.25 | 1.5 | 3.5 | 4 | 0.62 | 2.38 | 1.5 | 1.25 | 0.75 | 1/2 | 2 1/4 | 2 3/4 | 3 | 0.3 | 5 | 0.4 | 21 | 2.7 | 9 |
| 3/4 | 0.75 | 0.74 | 3.88 | 0.5 | 1.69 | 1.62 | 1.88 | 3.88 | 4 | 0.62 | 2.75 | 1.88 | 1.62 | 0.75 | 1/2 | 2 1/2 | 3 | 5 | 0.5 | 7 | 0.7 | 27 | 3.2 | 9 |
| 1 | 1 | 0.96 | 4.25 | 0.56 | 2 | 2 | 2.25 | 4.25 | 4 | 0.62 | 3.12 | 2.25 | 2 | 0.75 | 1/2 | 2 1/2 | 3 | 7 | 0.7 | 10 | 0.9 | 30 | 3.8 | 9 |
| 1 1/4 | 1.25 | 1.28 | 4.62 | 0.62 | 2.5 | 2.38 | 2.62 | 4.62 | 4 | 0.62 | 3.5 | 2.62 | 2.38 | 0.75 | 1/2 | 2 3/4 | 3 1/4 | 10 | 0.9 | 12 | 1.2 | 36 | 4.4 | 9 |
| 1 1/2 | 1.5 | 1.5 | 5 | 0.69 | 2.88 | 2.62 | 3 | 5 | 4 | 0.62 | 3.88 | 3 | 2.62 | 0.75 | 1/2 | 2 3/4 | 3 1/4 | 12 | 1 | 16 | 1.5 | 41 | 5.1 | 9 |
| 2 | 2 | 1.94 | 6 | 0.75 | 3.62 | 3.06 | 3.69 | 6 | 4 | 0.75 | 4.75 | 3.69 | 3.06 | 0.88 | 5/8 | 3 1/4 | 3 3/4 | 15 | 1.2 | 23 | 2.2 | 57 | 7.1 | 9 |
| 2 1/2 | 2.5 | 2.32 | 7 | 0.88 | 4.12 | 3.75 | 4.44 | 7 | 4 | 0.75 | 5.5 | 4.44 | 3.75 | 0.88 | 5/8 | 3 1/2 | 4 | 22 | 1.7 | 34 | 3.2 | 79 | 10 | 9 |
| 3 | 3 | 2.9 | 7.5 | 0.94 | 5 | 4.25 | 4.94 | 7.5 | 4 | 0.75 | 6 | 4.94 | 4.25 | 0.88 | 5/8 | 3 1/2 | 4 1/4 | 25 | 2 | 38 | 3.6 | 86 | 11 | 9 |
| 3 1/2 | 3.5 | 3.36 | 8.5 | 0.94 | 5.5 | 4.88 | 5.94 | 8.5 | 8 | 0.75 | 7 | 5.94 | 4.88 | 0.88 | 5/8 | 3 1/2 | 4 1/4 | 32 | 2.6 | 55 | 5.3 | 110 | 13 | 9 |
| 4 | 4 | 3.83 | 9 | 0.94 | 6.19 | 5.5 | 6.44 | 9 | 8 | 0.75 | 7.5 | 6.44 | 5.5 | 0.88 | 5/8 | 3 1/2 | 4 1/4 | 47 | 3.2 | 78 | 6 | 164 | 14 | 12 |
| 5 | 5 | 4.81 | 10 | 0.94 | 7.31 | 6.50 | 7.25 | 10 | 8 | 0.88 | 8.5 | 7.25 | 6.50 | 1 | 3/4 | 3 3/4 | 4 1/2 | 57 | 3.8 | 87 | 6.50 | 189 | 17 | 12 |
| 6 | 6 | 5.76 | 11 | 1 | 8.5 | 7.75 | 8.25 | 11 | 8 | 0.88 | 9.5 | 8.25 | 7.75 | 1 | 3/4 | 4 | 4 1/2 | 75 | 5.4 | 103 | 7.8 | 216 | 19 | 12 |
| 8 | 8 | 7.62 | 13.5 | 1.12 | 10.62 | 9.75 | 10.5 | 13.5 | 8 | 0.88 | 11.75 | 10.5 | 9.75 | 1 | 3/4 | 4 1/4 | 4 3/4 | 102 | 6.9 | 157 | 11 | 292 | 26 | 12 |
| 10 | 10 | 9.56 | 16 | 1.19 | 12.75 | 12 | 12.81 | 16 | 12 | 1 | 14.25 | 12.81 | 12 | 1.12 | 7/8 | 4 3/4 | 5 1/4 | 143 | 9.8 | 214 | 16 | 382 | 35 | 12 |
| 12 | 12 | 11.38 | 19 | 1.25 | 15 | 14.38 | 15.56 | 19 | 12 | 1 | 17 | 15.56 | 14.38 | 1.12 | 7/8 | 4 3/4 | 5 1/2 | 205 | 14 | 329 | 25 | 535 | 48 | 12 |
| 14 | 14 | 14 | 21 | 1.38 | 16.25 | 16 | 17.12 | 21 | 12 | 1.12 | 18.75 | 17.12 | 16 | 1.25 | 1 | 5 1/4 | 6 | 211 | 13 | 296 | 22 | 585 | 55 | 12 |
| 16 | 16 | 16 | 23.5 | 1.44 | 18.5 | 18 | 19.62 | 23.5 | 16 | 1.12 | 21.25 | 19.62 | 18 | 1.25 | 1 | 5 1/2 | 6 | 246 | 15 | 388 | 29 | 714 | 66 | 12 |
| 18 | 18 | 18 | 25 | 1.56 | 21 | 20 | 20.94 | 25 | 16 | 1.25 | 22.75 | 20.94 | 20 | 1.38 | 1 1/8 | 6 | 6 1/2 | 270 | 17 | 362 | 25 | 711 | 67 | 12 |
| 20 | 20 | 20 | 27.5 | 1.69 | 23 | 22 | 23.19 | 27.5 | 20 | 1.25 | 25 | 23.19 | 22 | 1.38 | 1 1/8 | 6 1/4 | 7 | 311 | 19 | 434 | 31 | 840 | 79 | 12 |
| 24 | 24 | 24 | 32 | 1.88 | 27.25 | 26.25 | 27.5 | 32 | 20 | 1.38 | 29.5 | 27.5 | 26.25 | 1.5 | 1 1/4 | 7 | 7 3/4 | 423 | 25 | 574 | 40 | 1046 | 100 | 12 |
Weight Chart Of Long Weld Neck Flanges
| Nominal Pipe Sizes (NPS) | Slip On (SORF) | Threaded (NPT) | Socket Weld (SWRF) | Lap Joint (Loose) | Blind (BLRF) | Weld Neck (WRNR) |
| ½ | 1 | 1 | 2 | 1 | 2 | 2 |
| ¾ | 2 | 2 | 2 | 2 | 2 | 2 |
| 1 | 2 | 2 | 2 | 2 | 2 | 3 |
| 1¼ | 3 | 3 | 3 | 3 | 3 | 3 |
| 1½ | 3 | 3 | 3 | 3 | 4 | 4 |
| 2 | 5 | 5 | 5 | 5 | 5 | 6 |
| 2½ | 8 | 8 | 8 | 8 | 7 | 10 |
| 3 | 9 | 9 | 9 | 9 | 9 | 11.5 |
| 3½ | 11 | 12 | 11 | 11 | 13 | 12 |
| 4 | 13 | 13 | 13 | 13 | 17 | 16.5 |
| 5 | 15 | 15 | 15 | 15 | 20 | 21 |
| 6 | 19 | 19 | 19 | 19 | 27 | 26 |
| 8 | 30 | 30 | 30 | 30 | 47 | 42 |
| 10 | 43 | 43 | 43 | 43 | 70 | 54 |
| 12 | 64 | 64 | 64 | 64 | 123 | 88 |
| 14 | 90 | 90 | 90 | 105 | 140 | 114 |
| 16 | 106 | 98 | 98 | 140 | 180 | 140 |
| 18 | 130 | 130 | 130 | 160 | 220 | 165 |
| 20 | 165 | 165 | 165 | 195 | 285 | 197 |
| 22 | 185 | 185 | 185 | 245 | 355 | 225 |
| 24 | 220 | 220 | 220 | 275 | 430 | 268 |
Long Weld Neck Flange Standard Manufacturing Materials
| Dimensions | Base Material | Pressure Rating |
|---|---|---|
| ASME B16.5 | ASTM A182 (Forgings) ASTM A240 (Plate) | 150#. 300#. 400#. 600#. 900#. 1500#. 2500#. |
| API 605 | ASTM A182 (Forgings) ASTM A240 (Plate) | 150#. 300#. 400#. 600#. 900#. 1500#. 2500#. |
| ASME B16.47series A & B | ASTM A182 (Forgings) ASTM A240 (Plate) | 150#. 300#. 400#. 600#. 900#. 1500#. 2500#. |
| EN1092-1 | ASTM A182 (Forgings) | PN2.5. PN6. PN10. PN16. PN25. PN40. PN63. PN100. PN160. PN250. PN320. PN400. |
| BS4504 | BS970 (Bar)ASTM A240 (Plate) ASTM A182 (Forgings) | PN2.5. PN6. PN10. PN16. PN25. PN40. PN63. PN100. PN160. |
| BS10 | BS970 (Bar)ASTM A240 (Plate) ASTM A182 (Forgings) |
Uses & Applications
Kaizen Steel Industries is proud to be a top supplier and exporter of high-quality fasteners, designed to meet diverse customer needs in various fields, including:
- Construction
- Bridges
- Petrochemical Industry
- Shipbuilding
- Engineering
- General Structural Purposes
- Offshore and Onshore Services
- Power Generation Industries
- Food Processing Industries
- Oil & Gas Industries
- Sugar Industries
Kaizen Steel Industries Export to
Burundi, Comoros, Djibouti, Eritrea, Ethiopia, Kenya, Madagascar, Malawi, Mauritius, Mayotte, Mozambique, Reunion, Rwanda, Seychelles, Somalia, Tanzania, United Republic of Uganda, Zambia, Zimbabwe, Angola, Cameroon, Central African Republic, Chad, Congo (Brazzaville), Congo, Democratic Republic of the Equatorial Guinea, Gabon, Sao Tome and Principe, Algeria, Egypt, Libyan Arab Jamahiriya, Morroco, South Sudan, Sudan, Tunisia, Western Sahara, Botswana, Lesotho, Namibia, South Africa, Swaziland, Benin, Burkina Faso, Cape Verde, Cote d\\’Ivoire (Ivory Coast), Gambia, Ghana, Guinea, Guinea-Bissau, Liberia, Mali, Mauritania, Niger, Nigeria, Saint Helena, Senegal, Sierra Leone, Togo
Anguilla, Antigua and Barbuda, Aruba, Bahamas, Barbados, Bonaire, Saint Eustatius and Saba, British Virgin Islands, Cayman Islands, Cuba, Curaçao, Dominica, Dominican Republic, Grenada, Guadeloupe, Haiti, Jamaica, Martinique, Monserrat, Puerto Rico, Saint-Barthélemy, St. Kitts and Nevis, Saint Lucia, Saint Martin, Saint Vincent and the Grenadines, Sint Maarten, Trinidad and Tobago, Turks and Caicos Islands, Virgin Islands (US), Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Falkland Islands (Malvinas), French Guiana, Guyana, Paraguay, Peru, Suriname, Uruguay, Venezuela, Bermuda, Canada, Greenland, Saint Pierre and Miquelon, United States
Afghanistan, Armenia, Azerbaijan, Bangladesh, Bhutan, Brunei Darussalam, Cambodia, China, Georgia, Hong Kong, India, Indonesia, Japan, Kazakhstan, South Korea, Kyrgyzstan, Laos, Macao, Malaysia, Maldives, Mongolia, Myanmar (ex-Burma), Nepal, Phillipines, Singapore, Sri Lanka (ex-Ceilan), Taiwan, Tajikistan, Thailand, Timor Leste (West), Turkmenistan, Uzbekistan, Vietnam
Albania, Andorra, Belarus, Bosnia, Croatia, European Union, Faroe Islands, Gibraltar, Guerney and Alderney, Iceland, Jersey, Kosovo, Liechtenstein, Macedonia, Man, Island of Moldova, Monaco, Montenegro, Norway, Russia, San Marino, Serbia, Svalbard and Jan Mayen Islands, Switzerland, Turkey, Ukraine, Vatican City State (Holy See)
Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, United Kingdom
Bahrain, Iraq, Iran, Israel, Jordan, Kuwait, Lebanon, Oman, Palestine, Qatar, Saudi Arabia, Syria, United Arab Emirates, Yemen
