Womic Stainless Steel Co., Ltd
Superior Acid Resistance: Excellent in H₂SO₄ (all concentrations up to moderate temperature), H₃PO₄, and organic acids.
NACE MR0175 Compliant: Fully qualified for sour service (H₂S) up to 232°C.
Excellent SCC Resistance: High nickel prevents chloride SCC.
Good Weldability: Niobium stabilization eliminates the need for post-weld heat treatment.
Full Range: Butt-weld (ASME B16.9), socket-weld (B16.11), threaded (NPT).
International Certifications: ABS, BV, DNV, LR, NORSOK, NACE, ASME.
|
Standard |
Application |
Alloy 825 Grade |
|
ASME B16.9 |
Industrial butt-welding fittings (BW) |
UNS N08825 (WP825) |
|
ASME B16.11 |
Socket-welding and threaded fittings (SW / NPT) |
UNS N08825 |
|
ASTM B366 |
Factory-made wrought nickel alloy fittings |
WPN8 825 |
|
MSS SP-43 |
Light-wall butt-welding fittings |
N08825 |
|
EN 10253-2 (Type B) |
European standard butt-welding fittings |
2.4858 (NiCr21Mo) |
|
EN 10253-4 |
European standard socket-welding fittings |
NiCr21Mo |
|
GB/T 12459 |
Chinese national standard seamless/welded fittings |
NS825 |
|
Element |
Ni |
Cr |
Fe |
Mo |
Cu |
Ti |
C |
Mn |
P |
S |
Si |
|
Alloy 825 |
38.0–46.0 |
19.5–23.5 |
≥22.0 |
2.5–3.5 |
1.5–3.0 |
0.6–1.2 |
≤0.05 |
≤1.0 |
≤0.03 |
≤0.03 |
≤0.5 |
The addition of copper (1.5-3.0%) provides exceptional resistance to sulfuric and phosphoric acids, while titanium stabilizes against intergranular corrosion.
|
Property |
Unit |
Alloy 825 (Annealed) |
|
Tensile Strength |
MPa |
≥585 |
|
Yield Strength (0.2% offset) |
MPa |
≥240 |
|
Elongation |
% |
≥30 |
|
Hardness (Brinell) |
HBW |
≤200 |
|
Density |
g/cm³ |
8.14 |
|
Melting Range |
°C |
1350–1400 |
Heat Treatment
Condition:
Alloy 825 fittings are solution annealed at 925–1040°C followed by
water quenching. This treatment restores optimum corrosion resistance and
ductility.
|
Class |
Pressure Rating (psig) @ 100°F |
Pressure Rating (psig) @ 400°F |
Pressure Rating (psig) @ 600°F |
|
3000 LB |
2100 |
1750 |
1550 |
|
6000 LB |
4200 |
3500 |
3100 |
Note: Ratings are typical for nickel alloys; consult ASME B16.34 for exact values.
|
Fitting Type |
Main Forms |
Manufacturing Method |
|
Elbow |
45°, 90°, 180° (Long Radius LR / Short Radius SR) |
Seamless / Forged |
|
Tee |
Equal, Reducing |
Seamless / Forged |
|
Cross |
Equal, Reducing |
Fabricated |
|
Reducer |
Concentric, Eccentric |
Seamless / Forged |
|
Cap |
Flat, Elliptical |
Forged |
|
Stub End (Lap Joint) |
Long type, Short type |
Seamless |
|
Nipple |
Threaded one end, Both ends, Full thread |
Machined |
|
Parameter |
Butt-Weld Fittings (BW) |
Socket-Weld / Threaded Fittings (SW / NPT) |
|
Nominal Size (DN/NPS) |
1/2″ – 24″ |
1/8″ – 4″ (DN6 – DN100) |
|
Wall Thickness Schedule |
Sch10S, Sch40S, Sch80S |
3000LB, 6000LB |
|
Manufacturing Process |
Seamless (≤12″) / Fabricated (>12″) |
Forging + Machining |
Raw Material Selection: Certified Alloy 825 billet from Special Metals, VDM Metals, or equivalent.
Cutting & Heating: Precise cutting and induction heating.
Forming: Hot forging or extrusion under controlled temperature.
Solution Annealing: Heat treated at 925–1040°C followed by water quenching.
Machining & Beveling: Precision machining for SW/threaded; beveling for BW.
Pickling & Passivation: Special acid blend for nickel alloys.
Marking & Inspection: Laser/inkjet marked with grade, heat number, size, and standard.
|
Surface Finish |
Description |
|
Annealed & Pickled (AP) |
Standard industrial finish – matte, oxide-free. |
|
Mechanically Polished |
Smooth finish (180#–400# grit) for general use. |
|
Electropolished |
Extremely clean, smooth surface – for pharmaceutical/high-purity applications. |
|
Passivated |
Chemically treated to enhance passive oxide layer. |
Chemical Analysis: PMI 100% verification of Ni, Cr, Mo, Cu, Ti.
Mechanical Testing: Tensile, yield, elongation, hardness.
Dimensional Inspection: Go/no-go gauges, CMM.
NDT: 100% Penetrant Testing (PT); UT/RT upon request.
Corrosion Testing: Intergranular corrosion test (ASTM G28).
Sour Service Qualification: NACE MR0175 HIC/SSC testing upon request.
Third-Party Inspection: SGS, BV, DNV, TUV available.
|
Parameter |
Size Range |
Permitted Tolerance |
|
Elbow Angle |
All sizes |
±0.5° |
|
End Outside Diameter |
≤4″ / ≤8″ / >8″ |
±1.6 mm / ±2.4 mm / ±3.2 mm |
|
Wall Thickness |
All |
Not less than 87.5% of nominal |
|
Thread (NPT) |
All |
Per ANSI B1.20.1 |
Sulfuric Acid Plants: Coolers, piping, tank connections.
Phosphoric Acid Production: Evaporators, heat exchanger fittings.
Oil & Gas Sour Service: Amine regenerator piping, sour water strippers.
Offshore Chemical Injection: Methanol / glycol lines.
Pickling Plants: Acid recovery systems.
Flue Gas Desulfurization (FGD): Slurry piping connections.
Small bore fittings (≤2″): Cartons or woven bags with moisture-proof film.
Large bore fittings (≥2.5″): Wooden crates with foam padding, individual wrapping.
End Protection: Plastic caps for butt-weld ends; thread protectors for threaded ends.
Labeling: Each fitting has a sticker (material, heat number, size) plus waterproof shipping marks.
Womic Steel's Delivery Strengths:
Ready stock: 1/2″–12″ Sch10S/Sch40S – dispatch within 24 hours.
Direct shipping cooperation with global shipowners.
Professional loading teams ensure damage-free shipment.
Full NACE certification and MTR provided.
1. How does Alloy
825 compare to Alloy 20?
Alloy 825 has higher nickel and molybdenum, better resistance to reducing acids
and H₂S, and is costlier than Alloy 20.
2. Is Alloy 825
resistant to hydrochloric acid?
Limited – for concentrated HCl, consider Hastelloy C276.
3. Can 825
fittings be used in seawater?
Yes, but super duplex is more cost-effective for high-velocity seawater applications.
Complete Product Range: Butt-weld, socket-weld, and threaded fittings – one-stop purchasing.
Strict Quality Control: ISO 9001, PED, NACE certified.
Traceable Raw Materials: From approved mills (Special Metals, VDM).
Full Traceability: Heat number to finished fitting.
Experienced in Acid & Sour Service: Phosphoric acid, sulfuric acid, sour gas projects.
Global Delivery: Exported to over 50 countries.
Tel / WhatsApp:
Victor: +86 15575100681
Jack: +86 18390957568
E-mail: info@womicstainless.com
Website: www.womicsteel.com
Contact Womic Steel today for a competitive quote on Alloy 825 stainless steel pipe fittings. We offer certified quality, fast production lead times, and reliable global delivery to keep your pipeline projects running smoothly.
Stock Examples:
90° LR Elbow: 2″ Sch40S, 4″ Sch10S
Equal Tee: 2″×2″ Sch40S, 4″×4″ Sch10S
Concentric Reducer: 4″×2″ Sch40S, 6″×4″ Sch80S
Cap: 3″ Sch40S, 6″ Sch40S
Related Keywords:
ASME B16.9 Alloy 825 butt weld fittings, Incoloy 825 pipe elbows, N08825 equal
tee for acid service, Alloy 825 reducing tee for sour gas, 825 concentric
reducer NACE MR0175, Alloy 825 lap joint stub end flange, ASTM B366 WPN8C 825
fittings, EN 10253-2 2.4858 buttweld fitting, 3000LB Alloy 825 socket weld
elbow, 825 threaded nipple NPT high pressure, Alloy 825 pipe cap for H₂SO₄,
nickel alloy Incoloy 825 fittings for offshore, 825 vs 625 cost comparison,
high corrosion resistant nickel alloy fittings, NORSOK M-650 Alloy 825.
