Order SS 310/310S Buttweld Fittings, Flanges & Outlet Connections – Suitable for High-Performance Industrial Applications – NACE, PED, IBR Approved.
We are a leading ISO-certified manufacturer and global supplier of premium stainless steel components, offering a full product range in Stainless Steel 310—a low-carbon version of SS 310S with improved weldability and excellent corrosion resistance in harsh environments. Our inventory includes SS 310 Buttweld Fittings, Flanges, Forged Fittings, and Branch Outlet Fittings (Olets), widely used in industries such as pharmaceuticals, marine engineering, petrochemicals, food processing, and water treatment. We are known for delivering high-quality products with full traceability, 100% testing, and export-grade packaging for global shipments.
Stainless Steel 310S is a molybdenum-containing austenitic alloy with low carbon content, which minimizes the risk of carbide precipitation during welding. Our components conform to the following international standards: ASTM A403 / ASME B16.9 for Buttweld Fittings, ASTM A182 / ASME B16.5 & B16.47 for Flanges, ASTM A182 / ASME B16.11 for Forged Fittings, and ASTM A182 / MSS SP-97 for Olets. We offer buttweld fittings from 1/2” to 48”, forged fittings in sizes 1/8” to 4”, and flanges ranging from 1/2” NB to 24” NB in pressure classes 150#, 300#, 600#, 900#, 1500#, and 2500#. All items are supplied with material test certificates as per EN 10204 3.1/3.2 and meet NACE, PED, and IBR requirements.
Our SS 10 Buttweld Fittings include 90°/45° elbows, concentric/eccentric reducers, tees (equal & reducing), stub ends, and end caps, manufactured to ASME B16.9. We also supply Forged Fittings in Socket Weld and Threaded types such as elbows, tees, couplings, unions, bushings, caps, plugs, and swage nipples—all made to ASME B16.11 standards. Our Flanges are manufactured in types like Weld Neck, Slip-On, Blind, Lap Joint, Socket Weld, and Threaded as per ASME B16.5/B16.47. We maintain a ready stock of Branch Connection Fittings (Olets) including Weldolets, Sockolets, Threadolets, Nipolets, and Latrolets made as per MSS SP-97.
SS 310S is ideal for chloride-containing environments due to its excellent pitting and crevice corrosion resistance. Its low carbon content ensures improved weldability and resistance to sensitization, making it suitable for applications in welded constructions, pressure vessels, pipelines, and cleanroom installations. Industries such as pharmaceuticals, food & beverage, offshore drilling, and chemical processing benefit from its long service life, hygienic properties, and high performance in both ambient and elevated temperatures.
Stockist of Stainless Steel 310/310S Flanges (WNRF, SORF, Blind), Buttweld Elbows, Tees, Reducers, Forged Couplings, Unions, Bushings, and Olets (Weldolet, Sockolet, Threadolet) – As per ASME B16.5, B16.9, B16.11, MSS SP-44 – Pressure Classes 150# to 2500#.
Technical Index
Industrial Stainless Steel 310/310S Specifications
| Material Grade | Stainless Steel 310, 310S / 1.4841, 1.4845 / UNS S31000, S31008 |
|---|---|
| Available Product Types | Flanges, Buttweld Fittings, Forged Fittings, Olets |
| Flanges Size Range | ½” (15 NB) to 48” (1200 NB) |
| Class | 150, 300, 600, 900, 1500, 2500, PN6, PN10, PN16, PN25, PN40, PN64 |
| Standard Specifications | ASTM A182, A403 / ASME SA182, SA403 |
| Standards | ASME B16.5, B16.47 Series A & B, B16.48, EN 1092-1, DIN, BS4504, BS10, ISO 7005-1, GOST, JIS B2220, MSS SP-44, API 605 |
| Types | Weld Neck Flange (WNRF), Slip-On Flange (SORF), Socket Weld Flange (SWRF), Threaded Flange, Blind Flange (BLRF), Lap Joint Flange, Ring Type Joint Flange (RTJ), Long Weld Neck Flange, Reducing Flange, Expander Flange, Orifice Flange, Spectacle Blind Flange, Spacer Flange, Paddle Blank, Paddle Spacer, Raised Face (RF), Flat Face (FF), Large Male-Female (LMF), Small Male-Female (SMF), Tongue & Groove |
| Buttweld Fittings Size | ½” NB to 24” NB (seamless), ½” NB to 48” NB (welded) |
| Wall Thickness | SCH 10, SCH 20, SCH 40, SCH 80, SCH 160, XXS |
| Standards | ASME B16.9, MSS SP-75, EN 10253, DIN 2605/2615/2616, ISO 3419, JIS B2312 |
| Types | Elbow (90°, 45°, Long Radius, Short Radius), Tee (Equal & Reducing), Reducer (Concentric & Eccentric), Caps, Stub Ends |
| Forged Fittings Size | ½” NB to 4” NB (Socket Weld & Threaded) |
| Class | Class 2000, 3000, 6000, 9000 (psi) |
| Standards | ASME B16.11, MSS SP-83, MSS SP-95, JIS B2316 |
| Types | 90° Elbow, 45° Elbow, Tee, Cross, Full Coupling, Half Coupling, Pipe Cap, Union, Reducer Insert, Boss, Hex Head Bushing, Hex Head Plug, Square Head Plug, Round Head Plug, Bull Plug, Boss, Outlet, Hex Nipple, Swage Nipple. |
| Olets (Outlet Fittings) Size | Branch Sizes ½” to 24” | Run Pipe Sizes up to 36” (custom) |
| Class | 3000#, 6000#, 9000# |
| Standards | MSS SP-97, ASME B16.11, ANSI, DIN, EN, JIS (custom) |
| Types | Weldolet, Sockolet, Threadolet, Elbolet, Latrolet, Nipolet, Sweepolet, Brazolet |
| End Connection Types | Buttweld, Socket Weld, Threaded (NPT/BSP), Flanged (RF, FF, RTJ), Custom Branch Outlets |
| Testing & Certifications | EN 10204 3.1 & 3.2, NACE MR0175, NACE MR0103, IBR, PMI, Ultrasonic Test, Radiography, Magnetic Particle Inspection |
| Surface Finish Options | Pickled, Passivated, Mirror Finish, Satin Finish, Sandblasted, Coated (Black, Yellow Transparent, Zinc) |
| Manufacturing Capabilities | CNC Machining, Cold/Hot Forming, Beveling, Drilling, Induction Heating, Forging, Custom Fabrication |
| Raw Material Sources | India, Japan, South Korea, USA, Germany, Italy |
| Export Destinations | USA, UAE, Saudi Arabia, Qatar, Kuwait, Oman, Egypt, South Africa, Kenya, Nigeria, Singapore, Malaysia, Australia |
Industrial Stainless Steel 310 Standards
| ANSI/ASME B16.47 Flanges | ANSI/ASME B16.36 Flanges | ANSI/ASME B16.5 Flanges | Pr. EN1902-1 Flanges |
| DIN Flanges | JIS Flanges | BS 4504 Flanges | BS 10 Flanges |
| MSS SP-44 Flanges | JIS B2220 Flanges | KS B1503 Flanges | UNI Flanges |
| SABS/SANS 1123 Flanges | AS 2129, AS 4087 Flanges | ISO 9624, ISO 7005-1 Flanges | AWWA Flanges Standard |
| GOST Standard Flanges | API Flanges | AS/ANZ 4331.1 Flanges | Series A Flange |
| Series B Flange | SAE J518 Flanges | GB Flange | Norwegian Standard Flanges |
| 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. |
| ANSI/ASME B16.9 – Factory-Made Wrought Steel Buttwelding Fittings | ANSI/ASME B16.28 – Wrought Steel Short Radius Elbows and Returns | ANSI/ASME B16.25 – Buttwelding Ends(beval standards) | MSS SP-43 – Wrought and fabricated Butt welding Fittings for Light Wall Applications |
| MSS SP-75 – High Test Wrought Butt welding Fittings | DIN 2616 – Butt welding Pipe Fittings: Reducers | DIN 2617 – Butt welding Pipe Fittings: Caps | DIN28011 – Dished Ends(used in pressure vessels) |
| EN10253-1 Butt-welding Pipe Fittings(Non Alloy Steels) | EN10253-2 Butt-welding Pipe Fittings(Stainless/Alloy Steels) |
Stainless Steel 310/310S International Standards
| STANDARD | WERKSTOFF NR. | UNS | JIS | BS | GOST | AFNOR | EN |
|---|---|---|---|---|---|---|---|
| SS 310 | 1.4841 | S31000 | SUS 310 | 310S24 | 20Ch25N20S2 | – | X15CrNi25-20 |
| SS 310S | 1.4845 | S31008 | SUS 310S | 310S16 | 20Ch23N18 | – | X8CrNi25-21 |
Stainless Steel 310S Chemical Composition
| Grade | C | Mn | Si | P | S | Cr | Mo | Ni | Fe |
|---|---|---|---|---|---|---|---|---|---|
| SS 310 | 0.015 max | 2.0 max | 0.15 max | 0.020 max | 0.015 max | 24.00 – 26.00 | 0.10 max | 19.00 – 21.00 | 54.7 min |
| SS 310S | 0.08 max | 2.0 max | 1.00 max | 0.045 max | 0.030 max | 24.00 – 26.00 | 0.75 max | 19.00 – 21.00 | 53.095 min |
Stainless Steel 310 Mechanical Properties
| Density | Melting Point | Tensile Strength | Yield Strength (0.2%Offset) | Elongation |
|---|---|---|---|---|
| 7.9 g/cm3 | 1402 °C (2555 °F) | Psi – 75000 , MPa – 515 | Psi – 30000 , MPa – 205 | 40 % |
Stainless Steel Types
Stainless Steel 310/310S Industries & Applications
Stainless Steel 310S Flange Size Chart
| Flange Weights by Pressure Class and Size | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pipe Size | 150 # | 300 # | 600 # | 900 # | 1500 # | 2500 # | ||||||||||||
| WN | SO | BLD | WN | SO | BLD | WN | SO | BLD | WN | SO | BLD | WN | SO | BLD | WN | SO | BLD | |
| 1/2″ | 2 | 1 | 1 | 2 | 1 | 1 | 2 | 2 | 2 | SEE 1500 # WEIGHTS | 5 | 4 | 4 | 7 | 7 | 7 | ||
| 3/4″ | 2 | 2 | 2 | 3 | 3 | 3 | 4 | 3 | 3 | SEE 1500 # WEIGHTS | 6 | 5 | 6 | 8 | 8 | 8 | ||
| 1″ | 3 | 2 | 2 | 4 | 3 | 3 | 4 | 4 | 4 | SEE 1500 # WEIGHTS | 9 | 8 | 8 | 12 | 11 | 11 | ||
| 1 1/2″ | 4 | 3 | 3 | 7 | 6 | 6 | 8 | 7 | 8 | SEE 1500 # WEIGHTS | 13 | 12 | 13 | 25 | 22 | 23 | ||
| 2″ | 6 | 5 | 5 | 9 | 7 | 8 | 12 | 9 | 10 | SEE 1500 # WEIGHTS | 25 | 25 | 25 | 42 | 37 | 39 | ||
| 2 1/2″ | 8 | 7 | 7 | 12 | 10 | 12 | 18 | 13 | 15 | SEE 1500 # WEIGHTS | 36 | 36 | 35 | 52 | 55 | 56 | ||
| 3″ | 10 | 8 | 9 | 15 | 13 | 16 | 23 | 16 | 20 | 31 | 26 | 29 | 48 | 48 | 48 | 94 | 83 | 86 |
| 4″ | 15 | 13 | 17 | 25 | 22 | 27 | 42 | 37 | 41 | 53 | 53 | 54 | 73 | 73 | 73 | 145 | 125 | 130 |
| 5″ | 19 | 15 | 20 | 32 | 28 | 35 | 68 | 63 | 68 | 86 | 83 | 87 | 130 | 130 | 140 | 245 | 210 | 225 |
| 6″ | 24 | 19 | 26 | 42 | 39 | 50 | 81 | 80 | 86 | 110 | 110 | 115 | 165 | 165 | 160 | 380 | 325 | 345 |
| 8″ | 39 | 30 | 45 | 67 | 58 | 81 | 120 | 115 | 140 | 175 | 170 | 200 | 275 | 260 | 300 | 580 | 485 | 530 |
| 10″ | 52 | 43 | 70 | 91 | 81 | 124 | 190 | 170 | 230 | 260 | 245 | 290 | 455 | 435 | 510 | 1075 | 930 | 1025 |
| 12″ | 80 | 64 | 110 | 140 | 115 | 185 | 225 | 200 | 295 | 325 | 325 | 415 | 690 | 580 | 690 | 1525 | 1100 | 1300 |
| 14″ | 110 | 90 | 140 | 180 | 165 | 250 | 280 | 230 | 355 | 400 | 400 | 520 | 940 | NA | 975 | NA | NA | NA |
| 16″ | 140 | 98 | 180 | 250 | 190 | 295 | 390 | 330 | 495 | 495 | 425 | 600 | 1250 | NA | 1300 | NA | NA | NA |
| 18″ | 150 | 130 | 220 | 320 | 250 | 395 | 475 | 400 | 630 | 680 | 600 | 850 | 1625 | NA | 1750 | NA | NA | NA |
| 20″ | 180 | 165 | 285 | 400 | 315 | 505 | 590 | 510 | 810 | 830 | 730 | 1075 | 2050 | NA | 2225 | NA | NA | NA |
| 22″ | 225 | 185 | 355 | 465 | 370 | 640 | 720 | 590 | 1000 | NA | NA | NA | NA | NA | NA | NA | NA | NA |
| 24″ | 260 | 220 | 430 | 580 | 475 | 790 | 830 | 730 | 1250 | 1500 | 1400 | 2025 | 3325 | NA | 3625 | NA | NA | NA |
SS 310 Buttweld Fittings Dimensions
| NOMINAL PIPE SIZE | ALL FITTINGS | ALL FITTINGS | ALL FITTINGS | ELBOWS AND TEES | 180 DEG RETURN BENDS | 180 DEG RETURN BENDS | 180 DEG RETURN BENDS | REDUCERS | CAPS |
|---|---|---|---|---|---|---|---|---|---|
| NPS | O.D. at Bevel (1), (2) | I.D. at End (1), (3), (4) |
Wall Thickness (3) | Centre-to-End Dimension A,B,C,M | Centre-to-Centre O | Back-to-Face K | Alignment of Ends U | Overall Length H | Overall Length E |
| ½ to 2½ | 0.06 -0.03 |
0.03 | Not less than 87.5% of nominal thickness | 0.06 | 0.25 | 0.25 | 0.03 | 0.06 | 0.12 |
| 3 to 3 ½ | 0.06 | 0.06 | Not less than 87.5% of nominal thickness | 0.06 | 0.25 | 0.25 | 0.03 | 0.06 | 0.12 |
| 4 | 0.06 | 0.06 | Not less than 87.5% of nominal thickness | 0.06 | 0.25 | 0.25 | 0.03 | 0.06 | 0.12 |
| 5 to 8 | 0.09 -0.06 |
0.06 | Not less than 87.5% of nominal thickness | 0.06 | 0.25 | 0.25 | 0.03 | 0.06 | 0.25 |
| 10 to 18 | 0.16 -0.12 |
0.12 | Not less than 87.5% of nominal thickness | 0.09 | 0.38 | 0.25 | 0.06 | 0.09 | 0.25 |
| 20 to 24 | 0.25 -0.19 |
0.19 | Not less than 87.5% of nominal thickness | 0.09 | 0.38 | 0.25 | 0.06 | 0.09 | 0.25 |
| 26 to 30 | 0.25 -0.19 |
0.19 | Not less than 87.5% of nominal thickness | 0.12 | … | … | … | 0.19 | 0.38 |
| 32 to 48 | 0.25 -0.19 |
0.19 | Not less than 87.5% of nominal thickness | 0.19 | … | … | … | 0.19 | 0.38 |
SS 310S Forged Fittings Dimensions
| Size | OD | WT | SR 90 Deg Elbows Centre – Face A | Weight | LR 90 Deg Elbows Centre – Face A | Weight | SR 45 Deg Elbows Centre – Face B | Weight | ||
|---|---|---|---|---|---|---|---|---|---|---|
| mm | inch. | mm | mm | SCH | mm | kg | mm | kg | mm | kg |
| 500 | 20″ | 508 | 9.52 | STD | 508 | 93.5 | 762 | 140 | 318 | 85 |
| 12.7 | X.S | 508 | 124 | 762 | 186 | 318 | 112.5 | |||
| 450 | 18″ | 457 | 9.52 | STD | 457 | 75.6 | 686 | 113 | 286 | 56.5 |
| 12.7 | X.S | 457 | 100 | 686 | 150 | 286 | 75 | |||
| 400 | 16″ | 406.4 | 9.52 | STD | 406 | 59.5 | 610 | 89.3 | 254 | 45 |
| 12.7 | X.S | 406 | 78.7 | 610 | 118 | 254 | 59 | |||
| 350 | 14″ | 355.6 | 9.52 | STD | 356 | 45.4 | 533 | 68.1 | 222 | 34.1 |
| 12.7 | X.S | 356 | 60 | 533 | 90 | 222 | 45 | |||
| 300 | 12″ | 323.9 | 9.52 | STD | 305 | 35.4 | 457 | 53.1 | 190 | 26.6 |
| 12.7 | X.S | 305 | 46.7 | 457 | 70 | 190 | 35 | |||
| 250 | 10″ | 273.9 | 9.27 | STD | 254 | 24.1 | 381 | 36.1 | 159 | 18.1 |
| 12.7 | X.S | 254 | 32.5 | 381 | 48.8 | 159 | 24.4 | |||
| 200 | 8″ | 219.1 | 8.18 | STD | 203 | 13.6 | 305 | 20.4 | 127 | 10.2 |
| 12.7 | X.S | 203 | 20.9 | 305 | 30.9 | 127 | 15.5 | |||
| 150 | 6″ | 168.3 | 7.11 | STD | 152.4 | 6.8 | 229 | 10.1 | 95.2 | 5.1 |
| 10.97 | X.S | 152.4 | 10.2 | 229 | 15.3 | 95.2 | 7.7 | |||
| 125 | 5″ | 141.3 | 6.65 | STD | 127 | 4.8 | 190 | 6.8 | 79.4 | 3.4 |
| 9.5 | X.S | 127 | 6.5 | 190 | 10 | 79.4 | 5 | |||
| 100 | 4″ | 114.3 | 62 | STD | 101.6 | 2.8 | 152.4 | 4.2 | 63.5 | 2.1 |
| 8.56 | X.S | 101.6 | 3.9 | 152.4 | 5.7 | 63.5 | 2.9 | |||
| 80 | 3″ | 88.9 | 5.49 | STD | 76.2 | 1.45 | 114.3 | 2.18 | 50.8 | 1.1 |
| 7.62 | X.S | 76.2 | 1.95 | 114.3 | 2.86 | 50.8 | 1.45 | |||
| 65 | 21/2″ | 73 | 5.16 | STD | 63.5 | 0.95 | 95.2 | 1.46 | 44.4 | 0.73 |
| 71 | X.S | 63.5 | 1.27 | 95.2 | 1.82 | 44.4 | 0.91 | |||
| 50 | 2″ | 60.3 | 3.91 | STD | 50.8 | 0.5 | 76.2 | 0.72 | 34.9 | 0.36 |
| 5.54 | X.S | 50.8 | 0.68 | 76.2 | 1 | 34.9 | 0.5 | |||
| 40 | 11/2″ | 48.3 | 3.68 | STD | 38.1 | 0.26 | 57.1 | 0.4 | 28.6 | 0.2 |
| 58 | X.S | 38.1 | 0.35 | 57.1 | 0.5 | 28.6 | 0.25 | |||
| 32 | 11/4″ | 42.2 | 3.56 | STD | 31.75 | 0.18 | 47.6 | 0.28 | 25.4 | 0.14 |
| 4.85 | X.S | 31.75 | 0.24 | 47.6 | 0.39 | 25.4 | 0.2 | |||
| 25 | 1″ | 33.4 | 3.38 | STD | 25.4 | 0.11 | 38.1 | 0.15 | 22.2 | 09 |
| 4.55 | X.S | 25.4 | 0.14 | 38.1 | 0.19 | 22.2 | 0.11 | |||
| 20 | 3/4″ | 26.7 | 2.87 | STD | – | – | 28.6 | 08 | 11.1 | 04 |
| 3.91 | X.S | – | – | 28.6 | 0.11 | 11.1 | 05 | |||
| 15 | 1/2″ | 21.3 | 2.78 | STD | – | – | 38.1 | 08 | 15.9 | 04 |
| 3.73 | X.S | – | – | 38.1 | 0.10 | 15.9 | 05 | |||
Major Industrial Stainless Steel 310 Fittings & Flanges 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.