Stainless Steel 347H Butt Weld Pipe Fittings, ASTM A403 WP347H Elbow
347 elbow is a pipe fitting used to connect two pipes and change their direction. SS 347 type stainless steel is stabilized with niobium and has enhanced resistance to intergranular corrosion. It has excellent resistance to oxidation and corrosion in high temperature environments up to 800-850°C. The elbow is available in 45°, 90° and 180° angles. Of course, our supplier also provides SS 347 Pipe Fittings, including Tees, Crosses, Caps, Reducers, Lap Joint Stub Ends, Long Radius Bend Returns, etc.
ASTM A403 Wp347 Material Specification
| Specification | ASTM A403 Stainless Steel 347 Pipe Fittings |
|---|---|
| Forms | Tees, Crosses, Reducers, 90º Elbows, Stub End, Pipe Bend, 45º Elbows, Pipe Cap |
| Size Range | ½" NB to 24" NB in Sch 10s, 40s, 80s, 160s, XXS. (DN6~DN100) |
| size | Seamless ButtWeld Fittings: 1/2 - 10 inch Welded Butt Weld Fittings: 1/2" - 48" |
| Dimensions | ASME B16.28, MSS-SP-43, ASME/ANSI B16.9 |
| Connection | Welding |
| Bending Radius | R=2D, 3D, 5D, 6D, 8D, 1D, 10D or Custom |
| Thickness | SCH10, SCH 80, SCH 100, SCH20, SCH30, STD SCH40, SCH 160, XXS, SCH60, XS, SCH 120, SCH 140 |
| Manufacturing process | Press, Forge, Push, Cast, etc. |
ASME SA403 WP347 Elbow Advantages
Compared to Alloy 321, Alloy 347 grade has slightly better oxidation resistance. 347 elbows are usually cut and forged from 347 stainless steel pipes. In addition to analyzing the chemical and product details, UNS S34700 tees specified in ASTM A403 also require tensile testing and visual inspection to see if there are surface discontinuities and surface cracks.
ASTM A403 WP347 Elbow Applications
- Power Generation
- Petroleum Refineries
- Pressure Vessels
- Aircraft Engine Components
- Heat Exchangers
- Chemical Processing
- Boilers
Manufacturing Scope: ASME B16.9 WP347 Butt-Weld Fittings
To ensure accurate alignment, uniform wall thickness, and seamless integration with process piping systems, all factory-made wrought butt-welding fittings must comply with the dimensional parameters of ASME B16.9.
Our specialized production covers the complete family of stabilized 347 stainless steel welded fittings, designed to sustain structural loads without wall thinning:
ASTM A403 WP347 Elbows: Available in 45-degree, 90-degree, and 180-degree configurations, across both Long Radius (LR - 1.5D) and Short Radius (SR - 1D) formats to manage fluid dynamics and space restrictions.
ASME B16.9 WP347 Tees: Equal tees and reducing tees engineered to handle directional fluid branching without inducing localized pressure drop stress.
Concentric & Eccentric Reducers: Precision-tapered fittings used to seamlessly shift pipeline diameters while maintaining centerline alignment (concentric) or flat-bottom drainage alignment (eccentric).
Caps & Stub Ends: Heavy-duty end closures and lap-joint stub ends for flexible system cleaning and modular line integration.
Technical Dimensions & Weight Matrix for WP347 90° Long Radius Elbows
When calculating structural piping supports and fluid flow pressures, engineering teams require precise dimensional transparency. The following chart details standard parameters for ASME B16.9 WP347 90° Long Radius (LR) Elbows matching standard wall schedules:
| Nominal Pipe Size (NPS) | Outer Diameter (OD) | Center-to-End dimension (A) | Approx. Weight (SCH 10S) | Approx. Weight (SCH 40S) | Approx. Weight (SCH 80S) |
| 1" (DN 25) | 33.40 mm | 38.00 mm | 0.16 kg | 0.20 kg | 0.26 kg |
| 1-1/2" (DN 40) | 48.30 mm | 57.00 mm | 0.36 kg | 0.47 kg | 0.63 kg |
| 2" (DN 50) | 60.30 mm | 76.00 mm | 0.66 kg | 0.89 kg | 1.21 kg |
| 3" (DN 80) | 88.90 mm | 114.00 mm | 1.75 kg | 2.82 kg | 3.86 kg |
| 4" (DN 100) | 114.30 mm | 152.00 mm | 3.12 kg | 5.26 kg | 7.37 kg |
| 6" (DN 150) | 168.30 mm | 229.00 mm | 7.85 kg | 14.90 kg | 21.80 kg |
| 8" (DN 200) | 219.10 mm | 305.00 mm | 15.30 kg | 30 |
High-Temperature Pressure Ratings and Performance Factors
The structural stainless steel 347 fittings pressure rating is fundamentally determined by the thickness of the matching seamless or welded pipe grade it is paired with. Under pressure piping standards like ASME B31.3, the allowable design stress of Grade 347 outpaces Grade 304 at elevated baselines:
Resistance to Polythionic Acid SCC: In oil refinery environments (such as hydrocrackers and fluid catalytic cracking units), exposure to sulfur compounds during shutdowns can create polythionic acid, which causes rapid stress corrosion cracking in unstabilized grades. Grade WP347 offers complete resistance to this failure mode.
Welded Integrity Without Heat Treatment: Because the columbium integration permanently binds the internal carbon content, welding an ASTM A403 WP347 fitting does not deplete chromium along the heat-affected zone (HAZ), eliminating the need for post-weld annealing.
Contact us today to submit your dimensional drawings, specify your required wall schedules, and secure a volume-optimized commercial quote.
