Socket Weld Fittings
What are Socket Weld Fittings?
Socket Weld Fittings are high-pressure pipe connection components where a pipe is inserted into a recessed socket and then welded around the outer edge. This design provides strong, leak-proof joints, especially in small-bore piping systems handling high-pressure steam, fluids, or gases.
Manufactured in various types like elbows, tees, couplings, reducers, and unions, socket weld fittings conform to ASME B16.11 and are made from carbon steel, stainless steel, and alloy steel for durability under pressure.
Key Features
Leak-Proof
Jointing
Durable
Construction
Easy Installation
& Removal
Wide
Compatibility
Corrosion
Resistant
Specifications
| Specification Category | Parameter / Feature | Details / Options |
|---|---|---|
| Size Range | Nominal Size | ½” to 4″ (DN15 – DN100), custom sizes available |
| Pressure Ratings | ANSI / ASME Class | Class 150, 300, 600, 900, 1500, 2500 |
| PN Ratings | PN10, PN16, PN25, PN40, PN64, PN100 | |
| Product Types | Socket Weld Elbows | 45°, 90°, Street Elbows |
| Socket Weld Tees | Equal, Reducing | |
| Socket Weld Cross | Equal, Reducing | |
| Socket Weld Couplings | Full, Half, Reducing | |
| Socket Weld Caps | Standard, Heavy Duty | |
| Socket Weld Reducers | Concentric, Eccentric | |
| Material Options | Stainless Steel | ASTM A182 F304/L, F316/L, F321, F347 |
| Alloy Steel | ASTM A182 F5, F9, F11, F22, F91 | |
| Carbon Steel | ASTM A105, ASTM A350 LF2, ASTM A694 F42 – F70 | |
| Duplex / Super Duplex | ASTM A182 F51, F53, F55 | |
| Nickel Alloys | Monel, Inconel, Hastelloy, Alloy 20 | |
| Other Alloys | Copper Nickel (CuNi 70/30, 90/10), Titanium Grades | |
| Standards & Certifications | ASTM | ASTM A105, ASTM A182, ASTM B366 |
| ASME / ANSI | ASME B16.11, ANSI B16.11 | |
| MSS | MSS SP-79, MSS SP-83, MSS SP-95 | |
| European Standards | EN 10222, EN 10204 | |
| Certifications | ISO 9001, PED 2014/68/EU, NACE MR0175, IBR | |
| Design Features | End Connections | Socket Weld (to ASME B16.11) |
| Pressure Class | 2000#, 3000#, 6000#, 9000# | |
| Wall Thickness | As per ASME B16.11 & MSS SP standards | |
| Tolerance | As per ASTM / ASME / EN requirements | |
| Thread Options | Available in SW + Threaded combination (on request) | |
| Coating & Surface Finish | Anti-Corrosion Coating | Passivation, Anti-rust Oil |
| Optional Coatings | Galvanized, PTFE, Epoxy, Black Oxide | |
| Surface Finish | Mill Finish, Pickled, Polished, Shot Blasted | |
| Testing & Inspection | Pressure Testing | Hydrostatic, Pneumatic |
| Non-Destructive Testing | Radiography (RT), Ultrasonic (UT), Magnetic Particle (MPI), Dye Penetrant (DPT) | |
| Destructive Testing | Tensile, Hardness, Impact, Micro & Macro Examination |
Dimensions
| Fitting Type | Nominal Size (NPS) | Outer Diameter (OD) | Wall Thickness (Schedule) | Length (L) | End Connection | Pressure Rating | Material Options | Standard Compliance |
|---|---|---|---|---|---|---|---|---|
| Socket Weld Elbow | ½” – 4″ | 21.3 mm – 114.3 mm | Schedule 40, 80, 160 | 45° or 90° | Socket Weld | 2000#, 3000#, 6000#, 9000# | Carbon Steel, Stainless Steel, Alloy Steel | ASME B16.11, MSS SP-79 |
| Socket Weld Tee | ½” – 4″ | 21.3 mm – 114.3 mm | Schedule 40, 80, 160 | 100 mm – 200 mm | Socket Weld | 2000#, 3000#, 6000#, 9000# | Carbon Steel, Stainless Steel, Alloy Steel | ASME B16.11, MSS SP-79 |
| Socket Weld Cross | ½” – 4″ | 21.3 mm – 114.3 mm | Schedule 40, 80, 160 | 100 mm – 200 mm | Socket Weld | 2000#, 3000#, 6000#, 9000# | Carbon Steel, Stainless Steel, Alloy Steel | ASME B16.11, MSS SP-79 |
| Socket Weld Coupling | ½” – 4″ | 21.3 mm – 114.3 mm | Schedule 40, 80, 160 | 25 mm – 150 mm | Socket Weld | 2000#, 3000#, 6000#, 9000# | Carbon Steel, Stainless Steel, Alloy Steel | ASME B16.11, MSS SP-79 |
| Socket Weld Cap | ½” – 4″ | 21.3 mm – 114.3 mm | Schedule 40, 80, 160 | 50 mm – 200 mm | Socket Weld | 2000#, 3000#, 6000#, 9000# | Carbon Steel, Stainless Steel, Alloy Steel | ASME B16.11, MSS SP-79 |
| Socket Weld Reducer | ½” – 4″ | 21.3 mm – 114.3 mm | Schedule 40, 80, 160 | 100 mm – 250 mm | Socket Weld | 2000#, 3000#, 6000#, 9000# | Carbon Steel, Stainless Steel, Alloy Steel | ASME B16.11, MSS SP-79 |
| Socket Weld Stub End | ½” – 4″ | 21.3 mm – 114.3 mm | Schedule 40, 80, 160 | 60 mm – 300 mm | Socket Weld | 2000#, 3000#, 6000#, 9000# | Carbon Steel, Stainless Steel, Alloy Steel | ASME B16.11, MSS SP-79 |
| Socket Weld Flange | ½” – 4″ | 21.3 mm – 114.3 mm | Schedule 40, 80, 160 | 120 mm – 250 mm | Socket Weld | 2000#, 3000#, 6000#, 9000# | Carbon Steel, Stainless Steel, Alloy Steel | ASME B16.5, ASME B16.11 |
Mechanical Properties
| Property | Value | Unit / Standard |
|---|---|---|
| Tensile Strength | 485 – 750 | MPa (Carbon Steel, Stainless Steel, Alloy Steel) |
| Yield Strength | 170 – 450 | MPa |
| Hardness | 120 – 200 | HB (Brinell) |
| Elongation | ≥ 20 – 30 | % |
| Density | 7.8 – 8.0 | g/cm³ |
| Impact Toughness | ≥ 27 – 70 | J (Charpy, grade-dependent) |
| Modulus of Elasticity (E) | ~200 | GPa |
| Fatigue Strength | 250 – 450 | MPa |
| Corrosion Resistance | Good to Excellent (SS > CS > Alloy Steel) | – |
| Thermal Conductivity | 15 – 50 | W/m·K |
| Coefficient of Thermal Expansion | 11 – 17 ×10⁻⁶ | /°C |
| Yield Ratio (YS/UTS) | 0.40 – 0.65 | – |
| Poisson’s Ratio | 0.27 – 0.30 | – |
| Brinell Hardness Range | 120 – 200 | HB |
| Surface Finish | As per ASME B16.11 – Smooth / Machined finish | – |
| Welding Type | Socket Weld connection (per ASME B16.11) | – |
| Operating Temperature Range | -46 to 600 | °C (material-dependent) |
| Pressure Rating | 2000#, 3000#, 6000#, 9000# | ASME B16.11 Standards |
Chemical Composition
| Element | SS 304 | SS 304L | SS 316 | SS 316L |
|---|---|---|---|---|
| Chromium (Cr) | 18.0 – 20.0 | 18.0 – 20.0 | 16.0 – 18.0 | 16.0 – 18.0 |
| Nickel (Ni) | 8.0 – 10.5 | 8.0 – 12.0 | 10.0 – 14.0 | 10.0 – 14.0 |
| Carbon (C) | ≤ 0.08 | ≤ 0.03 | ≤ 0.08 | ≤ 0.03 |
| Manganese (Mn) | ≤ 2.00 | ≤ 2.00 | ≤ 2.00 | ≤ 2.00 |
| Silicon (Si) | ≤ 1.00 | ≤ 1.00 | ≤ 1.00 | ≤ 1.00 |
| Phosphorus (P) | ≤ 0.045 | ≤ 0.045 | ≤ 0.045 | ≤ 0.045 |
| Sulfur (S) | ≤ 0.030 | ≤ 0.030 | ≤ 0.030 | ≤ 0.030 |
| Iron (Fe) | Balance | Balance | Balance | Balance |
| Molybdenum (Mo) | — | — | 2.0 – 3.0 | 2.0 – 3.0 |
Do you have questions?
What is the difference between socket weld and butt weld fittings?
Are socket weld fittings suitable for corrosive applications?
Do you offer socket weld fittings with NACE or IBR certifications?
What pressure classes are available?
