Premium Stainless Steel 347/347H Buttweld Pipe Fittings by Ratnadeep Steel & Engg. Co.
Ratnadeep Steel & Engg. Co. is a leading manufacturer, exporter, and supplier of premium-quality Stainless Steel 347 / 347H Buttweld Pipe Fittings. These fittings are manufactured from niobium (columbium)-stabilized austenitic stainless steels using advanced production techniques to ensure excellent mechanical strength, precise dimensional accuracy, and long-term service reliability. Our SS 347 and 347H buttweld fittings are extensively used in high-temperature and corrosive environments where resistance to intergranular corrosion, oxidation, and structural degradation is critical.
Stainless Steel 347 and 347H grades are specifically designed for elevated-temperature applications and resistance to carbide precipitation during welding and prolonged exposure to heat. Niobium stabilization prevents intergranular corrosion, while the higher carbon content in 347H enhances creep strength and stress rupture properties at elevated temperatures. Their buttweld pipe fittings are supplied with precision-beveled ends, enabling full-penetration welding that produces strong, leak-free, and permanent joints.
These fittings ensure a smooth and continuous internal flow path throughout the piping system, minimizing turbulence and pressure loss while improving resistance to oxidation, thermal fatigue, and high-temperature corrosion. As a result, SS 347 / 347H buttweld pipe fittings are ideal for applications in heat exchangers, superheaters, refinery and petrochemical piping, power generation systems, exhaust manifolds, and high-temperature chemical processing lines.
- Stainless Steel 347 90° Elbow
- ASTM A403 SS 347H 45° Elbow
- UNS S34700 180° Elbow
- UNS S34709 LR Elbow
- DIN 1.4550 SR Elbow
- ANSI B16.9 SS 347 90° Short Radius Elbow
- DIN 1.4961 45° Long Radius Elbow
- SS ASTM A403 WP347 Equal Tee
- ASME B16.9 SS 347 Pipe Tee
- DIN 1.4550 Butt weld Tee
- ASME SA403 Stainless Steel 347H Reducing Tee Manufacturer
- DIN 1.4961 Unequal Tee
- UNS S34700 / S34709 Tees
- A403 WP347H SS Straight Tee
- B16.9 Stainless Steel 347 Eccentric Reducer Supplier
- ASTM A403 Stainless Steel WP347H Eccentric Reducer
- SS UNS S34700 / S34709 Eccentric Reducers
- DIN 1.4550 / 1.4961 Eccentric Reducer
- ANSI B16.9 Stainless Steel 347 Concentric Reducer Supplier
- SS ASME SA 403 WP347H Concentric Reducer
- UNS S34700 / S34709 Concentric Reducers
- SS DIN 1.4550 / 1.4961 Concentric Reducer
- ASME B16.9 SS 347 Long Stub End Supplier
- ASTM A403 WP347H SS Long Stub Ends
- UNS S34700 / S34709 Long Stub End
- SS 347/347H Lap Joint Stub End
- DIN 1.4550 / 1.4961 Long Stub End
- ASTM A403 SS 347 Short Stub End Supplier
- ASME B16.9 Stainless Steel A403 WP347H Short Stub Ends
- SS UNS S34700 / S34709 Short Stub Ends
- DIN 1.4550 / 1.4961 Short Stub End
- ASTM A403 / SA403 Stainless Steel WP347 Pipe Cap Supplier
- ASME B16.9 SS 347H End Pipe Cap
- SS UNS S34700 Pipe End Cap
- UNS S34709 Buttweld Cap
- A403 WP347H Buttweld Pipe Cap
- DIN 1.4550 / 1.4961 End Cap
- ASTM A403 Stainless Steel 347 Equal Cross
- ASME B16.9 SS 347H Buttweld Cross
- ASTM A403 WP347 / WP347H Cross
- SS UNS S34700 / S34709 Unequal Cross
- DIN 1.4550 / 1.4961 Reducing Cross
- ASME SA 403 SS 347 Pipe Bend Exporter
- B16.9 Stainless Steel 347H Piggable Bend
- UNS S34700 / S34709 U Bend
- SS DIN 1.4550 / 1.4961 Long Radius Bend
- ASTM A403 WP347/347H SS Buttweld Bend
CHEMICAL COMPOSITION OF STAINLESS STEEL 347/347H SEAMLESS AND WELDED PIPE FITTINGS
| Element | C | Cr | Mn | Ni | P | S | Si | Cb/Ta |
|---|---|---|---|---|---|---|---|---|
| SS 347 | 0.08 max | min: 17.0 max: 20.0 |
2.0 max | min: 9.0 max: 13.0 |
0.04 max | 0.30 max | 0.75 max | min:10x C max: 1.0 |
| SS 347H | min: 0.04 max: 0.10 |
min: 17.0 max: 20.0 |
2.0 max | min: 9.0 max: 13.0 |
0.03 max | 0.30 max | 0.75 max | min:10x C max: 1.0 |
MECHANICAL PROPERTIES OF ASME SA403 SS WP347 / 347H BUTTWELD PIPE FITTINGS
| Grade | Tensile Strength ksi (MPa) min | Yield Strength 0.2% ksi offset ksi (MPa) min | Elongation (% in 50mm) min | Hardness (Brinell) MAX | Hardness (Rockwell B) MAX |
|---|---|---|---|---|---|
| 347/347H | 75 (515) | 30 (205) | 40 | 201 | 95 |
SPECIFICATION OF SS 347/347H BUTTWELD FITTINGS
| Specifications | ASTM A403 / ASME SA403 |
|---|---|
| Dimensions | ASME/ANSI B16.9, ASME B16.28, MSS-SP-43, BS4504, BS4504, BS1560, BS10 ASME 16.11, MSS SP-79, 83, 95, 97, BS 3799 |
| Size | Seamless Butt Weld Fittings: ½” to 10″ | Welded Butt Weld Fittings: ½” to 48″ |
| Schedule | SCH10, SCH20, SCH30, STD SCH40, SCH60, XS, SCH 80, SCH 100, SCH 120, SCH 140, SCH 160, XXS available with NACE MR 01-75 |
| Bending Radius | R=1D, 2D, 3D, 5D, 6D, 8D, 10D or Custom |
| Type | Seamless / ERW / Welded / Fabricated |
| Thickness | 20 Swg., 18 Swg., 16 Swg., 14 Swg., 12 Swg., 10 Swg., & Sch. 10, Sch. 40, Sch. 80 etc. |
347/347H STAINLESS STEEL ASTM A403 BUTTWELD FITTINGS EQUIVALENT GRADES
| STANDARD | UNS | WNR. | EN | JIS | GOST |
|---|---|---|---|---|---|
| SS 347 | S34700 | 1.4550 | X6CrNiNb18-10 | SUS 347 | 08Ch18N12B |
| SS 347H | S34709 | 1.4961 | X6CrNiNb18-12 | SUS 347H | – |
PHYSICAL PROPERTIES OF ASTM A403 STAINLESS STEEL 347/347H PIPE FITTINGS
| Density lbm/in³ | Coefficient of Thermal Expansion (min/in) °F | Thermal Conductivity BTU/hr-ft-°F | Specific Heat BTU/lbm-°F | Modules of Elasticity (annealed)²-psi |
|---|---|---|---|---|
| at 68 °F: 0.288 | at 68 – 212°F: 9.2 at 68 – 1832°F: 11.4 |
68-932°F: 14.7 | at 32 – 212°F: 0.12 | in tension (E): 28 × 10⁶ |
💡 Practical Difference in Use
Use Stainless Steel 347 / 347H Buttweld Pipe Fittings when: superior resistance to intergranular corrosion, excellent oxidation resistance, and reliable mechanical strength at elevated temperatures are required. These niobium (columbium)-stabilized grades are ideal for welded components exposed to prolonged high-temperature service where carbide precipitation and thermal degradation must be controlled. → Example: heat exchangers, superheaters, refinery piping, exhaust manifolds, petrochemical process lines, and high-temperature pressure systems.
Applications of SS 347 / 347H Buttweld Pipe Fittings
Stainless Steel 347 and 347H Buttweld Pipe Fittings are niobium-stabilized austenitic grades engineered for severe high-temperature service, offering excellent resistance to intergranular corrosion, oxidation, and thermal fatigue.
- Heat Exchangers & Superheaters: High-temperature fluid lines, headers, and tube connections.
- Petrochemical & Refining: Hot process piping, reformers, crackers, and elevated-temperature service lines.
- Power Generation: Boiler components, superheater piping, and high-temperature exhaust systems.
When to Choose SS 347 / 347H?
These grades are selected for applications that demand long-term stability at high temperatures along with excellent weldability and resistance to intergranular corrosion.
Choose SS 347 / 347H when:
- Operating temperatures exceed the safe limits of SS 304 / 304L
- Welded joints are exposed to prolonged or cyclic high-temperature service
- Niobium stabilization is required to prevent carbide precipitation
- Higher carbon 347H is needed for improved creep and stress-rupture strength
- Used in superheaters, heat exchangers, furnaces, and refinery process piping
Industries That Use SS 347 / 347H Buttweld Pipe Fittings
These fittings are widely used in industries where extreme temperature resistance, oxidation stability, and dependable welded performance are essential.
Designed for continuous service under severe thermal conditions.
Uses
Heat exchanger piping, superheaters, and high-temperature transfer lines.
Why SS 347 / 347H?
Niobium stabilization ensures resistance to intergranular corrosion and maintains strength at elevated temperatures.
Trusted for high-temperature and high-pressure process environments.
Uses
Reformer units, hot process piping, and refinery exhaust systems.
Why SS 347 / 347H?
Excellent oxidation resistance and thermal fatigue performance support long service life.
Used where sustained heat resistance and structural reliability are critical.
Uses
Boiler internals, superheater connections, and high-temperature exhaust piping.
Why SS 347 / 347H?
Enhanced creep strength and weld stability ensure safe operation under extreme temperatures.
Usage guide for SS 347 / 347H Buttweld Pipe Fittings
Smooth directional change in high-temperature and welded piping systems.
Choose Elbow when
- 45°, 90°, or 180° direction change is required
- Lines operate at elevated and sustained high temperatures
- Welded joints must resist intergranular corrosion
- Used in superheaters, heat exchangers, or refinery process piping
Creates strong branch connections for high-temperature service lines.
Choose Tee when
- Equal or reducing branch connections are required
- Piping is exposed to continuous or cyclic high temperatures
- Long-term weld stability is critical
- Used in petrochemical plants, refineries, or power generation systems
Maintains alignment while reducing pipe size in high-temperature pipelines.
Choose Eccentric Reducer when
- Avoiding air or vapor pockets is important
- Pump suction lines or horizontal high-temperature piping are used
- Thermal expansion and stress must be managed
- High-temperature strength and oxidation resistance are required
Uniform diameter transition for elevated-temperature piping systems.
Choose Concentric Reducer when
- Centered alignment is required
- Vertical or high-temperature piping systems are installed
- Smooth flow transition is necessary
- Used in superheaters and thermal process lines
Allows easy dismantling using lap joint flanges in hot service lines.
Choose Long Stub End when
- Frequent inspection or maintenance is required
- High-temperature and creep resistance at flange joints is needed
- Cost-effective solutions for large-diameter piping are preferred
- Used in refineries, power plants, or petrochemical systems
Compact lap joint connection for space-restricted high-temperature applications.
Choose Short Stub End when
- Space constraints exist
- Economical lap joint flange connections are required
- Used in heat exchangers or high-temperature process piping
- Resistance to intergranular corrosion is essential
Securely seals pipe ends in high-temperature service environments.
Choose Pipe Cap when
- Pipe ends must be permanently or temporarily closed
- Used for pressure testing or future line expansion
- Leak-proof sealing under elevated temperature and pressure is essential
- Exposed to oxidation and thermal cycling conditions
Four-way branching for complex high-temperature piping networks.
Choose Cross when
- Flow must be divided into multiple directions
- Used in refineries, petrochemical plants, or power stations
- Strong, oxidation-resistant welded joints are required
- Resistance to thermal fatigue and creep is critical
Large-radius directional change for smooth flow in high-temperature service lines.
Choose Pipe Bend when
- Gradual change in direction is required
- Used in superheaters, heat exchangers, or hot process piping
- Low turbulence and reduced pressure drop are important
- Long-term creep strength at elevated temperatures is required
Our Buttweld Pipe Fittings are manufactured using advanced processes and undergo extensive quality checks to ensure flawless weldability, durability, and long service life. Each fitting is thoroughly inspected using key NDT techniques such as radiographic testing (RT), ultrasonic testing (UT), hydrostatic testing, and visual/dimensional examination. We also perform detailed chemical composition analysis and mechanical property testing to ensure material compliance with strict industry standards.
Throughout the forming and welding stages, every buttweld fitting is monitored closely to eliminate defects such as misalignment, surface irregularities, and wall-thickness variations. This ensures perfect joint integrity and high-performance reliability in pipelines carrying high temperatures, pressures, and corrosive media. All our buttweld fittings fully comply with ASME, ASTM, MSS-SP, and related global specifications, making them a preferred choice for critical piping systems worldwide.
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