Views: 0 Author: Site Editor Publish Time: 2026-09-01 Origin: Site
Wenzhou Huashang specializes in the manufacturing of stainless steel and duplex stainless steel butt weld fittings in accordance with ASTM A815/A815M. Our products are widely used in petrochemical plants, offshore engineering, seawater systems, pulp and paper, flue gas desulfurization, pressure piping, and other corrosive service applications.
Huashang is capable of producing large-diameter duplex stainless steel butt weld fittings, with the maximum size available up to DN3000. Products can be customized according to drawings, material grades, wall thickness, pressure class, heat treatment, and inspection requirements.
Common duplex stainless steel grades covered by ASTM A815/A815M include S31803, S32205, S32750, S32760, S32550, S32950, and S39274. Duplex stainless steel combines high strength with excellent corrosion resistance, making it suitable for chloride-containing environments, seawater, acidic media, and demanding industrial piping systems.
UNS Grade | Cr % | Ni % | Mo % | N % | Other Key Elements |
S31803 | 21.0-23.0 | 4.5-6.5 | 2.5-3.5 | 0.08-0.20 | C max 0.030, Mn max 2.00 |
S32205 | 22.0-23.0 | 4.5-6.5 | 3.0-3.5 | 0.14-0.20 | C max 0.030, Mn max 2.00 |
S32750 | 24.0-26.0 | 6.0-8.0 | 3.0-5.0 | 0.24-0.32 | C max 0.030, Cu max 0.5 |
S32760 | 24.0-26.0 | 6.0-8.0 | 3.0-4.0 | 0.20-0.30 | Cu 0.50-1.00, W 0.50-1.00 |
S32550 | 24.0-27.0 | 4.5-6.5 | 2.9-3.9 | 0.10-0.25 | Cu 1.50-2.50 |
S32950 | 26.0-29.0 | 3.5-5.2 | 1.00-2.50 | 0.15-0.35 | C max 0.030, Mn max 2.00 |
S39274 | 24.0-26.0 | 6.0-8.0 | 2.50-3.50 | 0.24-0.32 | Cu 0.20-0.80, W 1.50-2.50 |
For super duplex grades such as S32760, ASTM A815/A815M also includes pitting resistance requirements such as Cr + 3.3Mo + 16N >= 40. The controlled content of chromium, molybdenum, and nitrogen helps improve resistance to pitting corrosion, crevice corrosion, and stress corrosion cracking.
UNS Grade | Yield Strength min ksi [MPa] | Tensile Strength min ksi [MPa] | Elongation min % | Hardness HBW max |
S31803 | 65 [450] | 90 [620] | 20 | 290 |
S32205 | 65 [450] | 95 [655] | 20 | 290 |
S32750 | 80 [550] | 116 [800] | 15 | 310 |
S32760 | 80 [550] | 109 [750] | 25 | 270 |
S32550 | 80 [550] | 110 [760] | 15 | 302 |
S32950 | 70 [485] | 100 [690] | 15 | 290 |
S39274 | 80 [550] | 116 [800] | 15 | 310 |
Compared with conventional austenitic stainless steel, duplex stainless steel usually provides higher yield strength while maintaining excellent corrosion resistance. This makes it a reliable material choice for large-diameter, heavy-wall, and high-performance piping projects.
For ASTM A815/A815M duplex stainless steel butt weld fittings, the following tests and inspections are generally required by the standard:
Mandatory Item | Applicable Scope | Requirement |
Chemical analysis | Each heat or cast of material | Chemical composition shall conform to ASTM A815/A815M Table 1. Test methods shall follow ASTM A751. |
Heat treatment verification | All WP and CR fittings | Fittings shall be heat treated in accordance with ASTM A815/A815M Table 2, unless specific exemption conditions apply. |
Tensile test | Material representative of finished fittings | Yield strength, tensile strength, and elongation shall conform to ASTM A815/A815M Table 3. The standard tensile specimen is base metal only. |
Hardness test | All fittings | Hardness shall not exceed the maximum HBW value specified in ASTM A815/A815M Table 3. |
Visual and surface examination | All fittings | Fittings shall be visually examined. Surface discontinuities deeper than 5% of nominal wall thickness are generally not permitted. |
Welding procedure and welder qualification | Welded fittings | Welders, welding operators, and welding procedures shall be qualified in accordance with ASME BPVC Section IX. |
NDE personnel qualification | Personnel performing NDE | Nondestructive examination personnel shall be qualified in accordance with SNT-TC-1A. |
Radiographic or ultrasonic examination | WP-W, WP-WX, and WP-WU fittings | WP-W requires radiographic examination as specified; WP-WX requires radiographic examination of all welds; WP-WU requires ultrasonic examination of all welds. |
Liquid penetrant examination for weld repair | Weld-repaired areas | Prepared cavities and repaired weld areas shall be examined by liquid penetrant testing in accordance with ASTM E165/E165M. Cracks are not permitted. |
Test report / material certificate | All delivered fittings | Reports shall include chemical analysis, starting material type, tensile properties, construction type, heat treatment, hardness, NDE results, and supplementary tests required by the purchase order. |
ASTM A815/A815M does not require hydrostatic testing as a mandatory test. However, Class WP and Class CR fittings shall be capable of withstanding the applicable pressure requirements. If actual hydrostatic testing is required, it should be clearly specified in the purchase order or technical agreement.
Wenzhou Huashang Manufacturing Capability
Wenzhou Huashang can supply ASTM A815/A815M duplex stainless steel butt weld fittings including elbows, tees, reducers, caps, stub ends, large-diameter welded fittings, and customized non-standard fittings. With strong forming, welding, heat treatment, and inspection capability, Huashang can manufacture duplex stainless steel butt weld fittings up to DN3000.
