Buy SS 347/347H Pipe Fittings & Flanges – Buttweld, Forged & Olets – Engineered for Service in Stress-Rupture & Oxidizing Conditions – Certified to NACE, PED & IBR.
As a trusted ISO-certified manufacturer and exporter, we specialize in delivering high-performance piping components in Stainless Steel 347/347H, a stabilized austenitic stainless steel ideal for high-temperature and corrosive environments. Designed with columbium (niobium) for improved stability, SS 347 is widely used in applications where resistance to intergranular corrosion and high-temperature creep strength are critical. We supply a complete range of SS 347H products including Buttweld Fittings, Forged Fittings, Flanges, and Olets, all backed by stringent quality control, timely delivery, and full traceability. Our global supply capability makes us a reliable partner for industries such as oil & gas, petrochemicals, refineries, heat exchangers, and aerospace.
Stainless Steel 347H exhibits excellent weldability and high-temperature resistance, especially in environments prone to thermal cycling. Our manufacturing covers all critical 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 from 1/8” to 4”, and flanges in 150# to 2500# pressure ratings, up to 24” NB. Each component is supplied with EN 10204 3.1 or 3.2 certification, along with complete MTCs, PMI reports, and third-party inspection support if required.
Our Buttweld Fittings in SS 347/347H include long and short radius elbows, concentric/eccentric reducers, tees, stub ends, and end caps – manufactured to meet ASME B16.9 dimensional tolerances. For high-pressure and compact installations, we supply Forged Fittings in Socket Weld and Threaded configurations such as 45°/90° elbows, straight/reducing tees, unions, caps, plugs, and swage nipples as per ASME B16.11. Our Flanges are available in various types including Weld Neck, Slip-On, Blind, Lap Joint, Socket Weld, and Threaded, designed as per ASME B16.5 & B16.47 standards. For pipeline branch connections, we provide Olet fittings such as Weldolets, Sockolets, Threadolets, and Nipolets under MSS SP-97 – ideal for reinforced connections in critical flow systems.
SS 347 offers exceptional resistance to high-temperature oxidation, creep, and intergranular corrosion after welding—making it a material of choice for heat exchanger tubes, furnace parts, pressure vessels, expansion joints, exhaust systems, and other thermal cycling environments. Its stabilized structure prevents carbide precipitation during welding, ensuring long-term corrosion resistance without the need for post-weld annealing. With superior formability, weldability, and durability, SS 347/347H continues to be a preferred material in refinery, aerospace, and thermal processing industries.
Stockist of Stainless Steel 347 Flanges (WNRF, SORF, Blind), Buttweld Elbows, Tees, Reducers, and Forged Fittings like Couplings, Unions, Bushings – Along with Weldolet, Sockolet & Threadolet – As per ASME B16.5, B16.9, B16.11, MSS SP-44 – Pressure Ratings 150# to 2500#.
Technical Index
Industrial Stainless Steel 347/347H Specifications
| Material Grade | Stainless Steel 347, 347H / 1.4550, 1.4961 / UNS S34700, S34709 |
|---|---|
| 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 347/347H 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 347/347H International Standards
| STANDARD | WERKSTOFF NR. | UNS | JIS | GOST | EN |
| SS 347 | 1.4550 | S34700 | SUS 347 | 08Ch18N12B | X6CrNiNb18-10 |
| SS 347H | 1.4961 | S34709 | SUS 347H | – | X6CrNiNb18-12 |
Stainless Steel 347H Chemical Composition
| Grade | C | Mn | Si | P | S | Cr | Cb | Ni | Fe |
| SS 347 | 0.08 max | 2.0 max | 1.0 max | 0.045 max | 0.030 max | 17.00 – 20.00 | 10xC – 1.10 | 9.00 – 13.00 | 62.74 min |
| SS 347H | 0.04 – 0.10 | 2.0 max | 1.0 max | 0.045 max | 0.030 max | 17.00 – 19.00 | 8xC – 1.10 | 9.0 -13.0 | 63.72 min |
Stainless Steel 347 Mechanical Properties
| Density | Melting Point | Tensile Strength | Yield Strength (0.2%Offset) | Elongation |
| 8.0 g/cm3 | 1454 °C (2650 °F) | Psi – 75000 , MPa – 515 | Psi – 30000 , MPa – 205 | 35 % |
Stainless Steel Types
Stainless Steel 347H Industries & Applications
Stainless Steel 347 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 347H 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 347 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 347 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.