Comprehensive Stock of ASME B16.11 Forged Unions – Threaded & Socket Weld End Connections – Supplied in ASTM A105 Carbon Steel, A182 F304L/F316L Stainless Steel, Alloy Steel F11/F22, Duplex and High-Performance Nickel-Based Alloys like Inconel 625, Monel 400 & Hastelloy C276.
Union fittings play a vital role in piping systems by providing a simple and reusable method for connecting two pipes or tubes. Unlike permanent welded or threaded joints, unions allow easy disassembly without causing damage to the piping, making them ideal for maintenance, repair, or replacement tasks. Typically composed of three parts — a nut, a female end, and a male end — unions create a secure, leak-tight seal when assembled correctly.
There are various types of unions designed to suit different applications, primarily socket weld unions and threaded unions. Socket weld unions are welded directly to pipe ends, ensuring a strong, permanent connection, while threaded unions use screw threads, allowing quick and convenient pipe disconnection. These fittings are available in sizes from 1/8” to 4” and pressure ratings such as Class 2000, 3000, 6000, and 9000, accommodating a wide range of industrial needs.
Manufactured according to stringent international standards like ASME B16.11 and MSS-SP-83, forged unions offer excellent strength, durability, and resistance to leaks. They are produced using a variety of materials, including Carbon Steel (ASTM A105, A350 LF2), Stainless Steel (ASTM A182 F304, F316, F321), Alloy Steel (F11, F22, F91), Duplex and Super Duplex Steel, and Nickel Alloys such as Inconel, Monel, and Hastelloy. Precision forging, heat treatment, and machining processes ensure that these unions meet high mechanical and dimensional standards, suitable for demanding pressure and corrosive environments.
Unions are widely used in sectors such as oil and gas, petrochemical, power generation, chemical processing, and marine engineering. Their ability to provide quick, reliable disconnection and reconnection makes them indispensable for systems requiring frequent maintenance or component replacement. With their robust construction and dependable sealing performance, forged unions contribute significantly to the safety, efficiency, and longevity of complex piping systems.
Industrial Forged Union – Conforming to ASME B16.11 Standards – Socket Weld and Threaded Configurations – Male & Female – Sizes 1/8”–4”, Class 2000/3000/6000/9000 – Engineered for leak-free flow division in critical fluid networks.
Technical Index
Industrial Forged Union Standard Specifications
| Forged Union Size Availability | 1/2″NB TO 4″NB IN (Threaded & Socket Weld) |
|---|---|
| Pressure Class Ratings | 2000LBS,3000LBS, 6000LBS, 9000LBS |
| Dimensions | ASME B16.11, MSS-SP-79, MSS-SP-83, MSS-SP-95, MSS-SP-97 |
| DIN | DIN 2986, 2999 |
| BS | BS 3799 |
| Thread | BSPP & BSPT Threads, NPTF & NPT Threads, UNF & UN Threads |
| Types | Threaded / Screwed Union, Male X Female Threaded Union |
| Material Grades | Carbon Steel (A105, A350 LF2), Stainless Steel (304/304L, 316/316L), Alloy Steel (F11, F22), Duplex, Super Duplex, Inconel, Monel, Hastelloy |
| Coating / Surface Treatment | Black Paint, Anti-rust Coating, Galvanized, Transparent Oil |
| Ends | Threaded Ends (NPT/BSP), Socket Weld Ends |
| Tolerance | As per ASME B16.11 |
| Testing | PMI, Hydro Test, UT, RT, Visual & Dimensional Inspection |
| Certification | EN 10204 3.1 / 3.2, ISO 9001:2015, PED 2014/68/EU (where applicable) |
| Material Sourcing Regions | India, South Korea, Japan, USA, Germany, Italy |
| Global Export Markets | UAE, Saudi Arabia, Oman, Qatar, Bahrain, Kuwait, USA, Malaysia, Singapore, Egypt, Nigeria, South Africa, Kenya, Ghana, Turkey, Brazil, Mexico |
Industrial Forged Union Standards
| ASME B16.11 – Forged Steel Fittings, Socket-Welding and Threaded | BS 3799 – Screwed and Socket-Welding for the Petroleum Industry | MSS SP-79 – Socket-Welding Reducer Inserts | MSS SP-83 – Class 3000 Steel Pipe Unions, Socket-Welding and Threaded |
| MSS SP-95 – Swage(d) Nipples and Bull Plugs | MSS SP-97 – Integrally Reinforced Forged Branch Outlet Fittings | DIN 2986 – Threaded Fittings | DIN 2999 – Pipe Threads for Fittings (British Standard Pipe Threads) |
| ISO 49 – Malleable Iron Fittings, Threaded | ISO 7/1 – Pipe Threads Where Pressure-tight Joints Are Made on the Threads | EN 10241 – Steel Threaded Pipe Fittings | JIS B2316 – Japanese standard for forged pipe fittings. |
Forged Socket weld Union Material Grades and Standards
| Stainless Steel Forged Union | ASTM / ASME A/SA 182: F 304, 304L, 304H, 309S, 309H, 310S, 310H, 316, 316TI, 316H, 316L, 316LN, 317, 317L, 321, 321H, 347, 347H, 904L |
|---|---|
| Duplex Steel Forged Union | ASTM A182 / ASME SA182 UNS S31803, S32205. Werkstoff No. 1.4462 |
| Super Duplex Steel Forged Union | ASTM A182 / ASME SA182 UNS S32750, S32760, S32950. Werkstoff No. 1.4410 |
| Carbon Steel Forged Union | ASTM A105/A694/ A350 LF3/A350 LF2: F42, F46, F52, F56, F60, F65, F70 |
| Alloy Steel Forged Union | ASTM A182: F1, F5, F9, F11, F22, F91 |
| High Nickel Alloy Forged Union | ASTM / ASME SB 564 / 160 / 472: UNS 2200 (NICKEL 200), UNS 4400 (MONEL 400), UNS 8825 INCONEL (825), UNS 6600(INCONEL 600), UNS 6601 (INCONEL 601), UNS 6625 (INCONEL 625), UNS 10276 (HASTELLOY C 276), UNS 2201 (NICKEL 201), (ALLOY 20 / 20 CB 3) |
| Brass Forged Union | Brass CA 360, CA 345 and CA 377 / SAE J530, SAE J531 and ASA |
ASME B16.11 Forged Fittings Types
Forged Socket weld Union Industries & Applications
ASME B16.11 Forged Union Dimensions
| DIMENSIONS OF THREADED UNION (BS3799) (in mm) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Nom Pipe Size (NPS) | Pipe End Min | Socket Bore Dia. | Socket Wall Min. | Water Way Bore | Laying Length | Male Flange Min. | Nut Min. | Threads Per 25.4 Max | Bearing Min. | Depth of Socket Min. | Length Assem. Nominal | Clear Assem. Nut |
| A | B | C | D | E | F | G | H | J | K | L | N | |
| 1 | 45.5 | 34.04 33.78 |
4.95 | 28.14 27.74 |
34.3 26.2 |
4.57 | 4.44 | 11 | 1.85 | 12.7 | 62.0 | 79.0 |
| ½ | 31.2 | 21.84 21.59 |
4.06 | 17.47 17.07 |
26.9 20.6 |
3.68 | 3.68 | 14 | 1.50 | 9.6 | 49.0 | 57.0 |
| ¼ | 21.8 | 14.22 13.97 |
3.30 | 9.85 9.45 |
22.4 19.0 |
3.17 | 3.17 | 19 | 1.24 | 9.6 | 41.4 | 49.0 |
| 1/8 | 21.8 | 10.92 10.67 |
3.17 | 6.83 6.43 |
22.4 19.0 |
3.17 | 3.17 | 16 | 1.24 | 9.6 | 41.1 | 49.0 |
| 3/8 | 25.9 | 17.78 17.53 |
3.48 | 13.92 13.51 |
26.9 20.6 |
3.43 | 3.43 | 14 | 1.37 | 9.6 | 46.0 | 55.0 |
| ¾ | 37.1 | 27.18 26.92 |
4.27 | 21.79 21.39 |
31.8 25.4 |
4.06 | 4.06 | 11 | 1.68 | 12.7 | 56.9 | 67.0 |
| 11/4 | 54.9 | 42.67 42.42 |
5.28 | 35.76 35.36 |
40.6 32.5 |
5.33 | 5.21 | 11 | 2.13 | 12.7 | 71.1 | 94.0 |
| 21/2 | 91.7 | 74.17 73.66 |
7.65 | 64.72 64.31 |
61.7 52.1 |
7.49 | 7.11 | 8 | 3.07 | 15.8 | 102.4 | 148.0 |
| 3 | 109.2 | 90.17 89.66 |
8.31 | 77.67 77.27 |
63.8 53.6 |
8.25 | 8.00 | 8 | 3.53 | 15.8 | 109.0 | 175.0 |
| 11/2 | 61.5 | 48.77 48.51 |
5.54 | 41.61 41.20 |
42.2 34.0 |
5.84 | 5.59 | 10 | 2.31 | 12.7 | 75.5 | 111.0 |
| 2 | 75.2 | 61.47 61.21 |
6.05 | 52.53 52.12 |
45.3 37.3 |
6.60 | 6.35 | 10 | 2.69 | 15.8 | 86.1 | 132.0 |
ASME B16.11 Socket Weld Union Dimensions
| Nominal Diameter | Wall Thickness | Outside Diameter | Socket Bore | Water way Bore | Length Assem Nominal |
Depth of Socket | |||
|---|---|---|---|---|---|---|---|---|---|
| Cmin | Dmin | d1 | d2 | L | Jmin | ||||
| DN | NPS | Socket | Threaded | Socket |
Threaded | Socket | Socket & Threaded | Socket & Threaded | Socket |
| 6 | 1/8 | 3.2 | 2.5 | 21.8 | 14.7 | 10.65 | 6.43 | 41.4 | 10 |
| 8 | 1/4 | 3.3 | 3.1 | 21.8 | 19.0 | 14.10 | 9.45 | 41.4 | 10 |
| 10 | 3/8 | 3.5 | 3.2 | 25.9 | 22.9 | 17.55 | 13.51 | 46.0 | 10 |
| 15 | 1/2 | 4.1 | 3.8 | 31.2 | 27.7 | 21.70 | 17.07 | 49.0 | 10 |
| 20 | 3/4 | 4.3 | 4.0 | 37.1 | 33.5 | 27.05 | 21.39 | 56.9 | 13 |
| 25 | 1 | 5.0 | 4.6 | 45.5 | 41.4 | 33.80 | 27.74 | 62.0 | 13 |
| 32 | 11/4 | 5.3 | 4.9 | 54.9 | 50.5 | 42.55 | 35.36 | 71.1 | 13 |
| 40 | 11/2 | 5.6 | 5.1 | 61.5 | 57.2 | 48.65 | 41.20 | 76.5 | 13 |
| 50 | 2 | 6.1 | 5.6 | 75.2 | 70.1 | 61.10 | 52.12 | 86.1 | 16 |
| 65 | 21/2 | 7.7 | 7.1 | 91.7 | 85.3 | 73.80 | 64.31 | 102.4 | 16 |
| 80 | 3 | 8.4 | 7.7 | 109.2 | 102.4 | 89.80 | 77.27 | 109.0 | 16 |
Weight Chart of ANSI B16.11 Forged Union
| Normal Pipe Sizes | A | B | QTY | Weight In KG |
|---|---|---|---|---|
| ¼ | 0.81 | 0.88 | 160 | 0.20 |
| ⁄ | 0.97 | 1.00 | 130 | 0.26 |
| ½ | 1.12 | 1.31 | 100 | 0.57 |
| ¾ | 1.31 | 1.5 | 75 | 0.71 |
| 1 | 1.5 | 1.81 | 40 | 1.08 |
| 1 ¼ | 1.75 | 2.19 | 25 | 1.68 |
| 1 ½ | 2.00 | 2.44 | 18 | 2.38 |
| 2 | 2.38 | 2.97 | 10 | 3.55 |
| 2 ½ | 3.00 | 3.62 | 4 | 6.22 |
| 3 | 3.38 | 4.31 | 2 | 10.36 |
| 4 | 4.19 | 5.75 | 1 | 23.91 |
Major Industrial Forged Threaded Union Export Countries
United Arab Emirates (UAE), Jordan, Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, United States of America (USA), Singapore, Malaysia, Azerbaijan, Armenia, Georgia, Egypt, Algeria, Nigeria, South Africa, Kenya, Morocco, Ethiopia, Ghana, Tanzania, Sudan, Uganda, Angola.