ASTM B564 UNS N08810 Weld Neck Flange Manufacturer & Supplier
We manufacture and supply ASTM B564 UNS N08810 weld neck flanges, also known as Incoloy 800H weld neck flanges, designed for use in high-temperature and corrosive service conditions. Produced in accordance with ASME, ANSI, DIN, EN, and MSS-SP standards, these flanges provide excellent strength, corrosion resistance, and dimensional accuracy.
The weld neck design ensures strong, leak-proof connections suitable for high-pressure piping systems. Each flange is supplied with full traceability, Mill Test Certificates (EN 10204 3.1/3.2), and optional NDT reports upon request.
ASTM B564 UNS N08810 Specifications
- Material: ASTM B564 UNS N08810 (Incoloy 800H)
- Equivalent Grades:
- Incoloy 800H
- W.Nr. 1.4958
- Alloy 800H
- Flange Types Available: ASTM B564 UNS N08810 Weld Neck Flange, ASTM B564 UNS N08810 Slip On Flange, ASTM B564 UNS N08810 Blind Flages, Socket Weld, Threaded, Lap Joint
- Size Range: ½” to 48″ (DN15–DN1200)
- Pressure Class: 150#, 300#, 600#, 900#, 1500#, 2500#
- Face Types: Raised Face (RF), Flat Face (FF), Ring Type Joint (RTJ)
- Standards: ASME B16.5, ASME B16.47, MSS-SP-44, DIN/EN standard sizes
Incoloy 800H, also known as “Alloy 800H”, is designated as UNS N08810 or DIN W.Nr. 1.4958. It has almost the same chemical composition as Alloy 800 except that it requires a higher carbon addition resulting in improved high-temperature properties. Compared to Incoloy 800, it has better creep and stress-rupture characteristics in the 1100°F [592°C] to 1800°F [980°C] temperature range. While Incoloy 800 is usually annealed at at approximately 1800°F [980°C], Incoloy 800H should be annealed at approximately 2100°F [1150°C].
Chemical Compostion of N08810 Flange
| Element | Nickel-Iron-Chromium Alloy (UNS N08800) | Nickel-Iron-Chromium Alloy (UNS N08810) |
| Nickel | 30.0 – 35.0 | 30.0 – 35.0 |
| Copper | 0.75 | 0.75 |
| Iron | 39.5 min | 39.5 min |
| Manganese | 1.5 | 1.5 |
| Carbon | 0.1 | 0.05 – 0.10 |
| Silicon | 1 | 1 |
| Sulfur | 0.015 | 0.015 |
| Chromium | 19.0 – 23.0 | 19.0 – 23.0 |
| Aluminum | 0.15 – 0.60 | 0.15 – 0.60 |
| Titanium | 0.15 – 0.60 | 0.15 – 0.60 |
| Columbium | … | … |
Mechnical Property of UNS N08810 Flange
| Material and Condition | Maximum Section Thickness or Diameter, in. (mm) | Tensile Strength, min, ksi (MPa) | Yield Strength, 0.2 % Offset, min, ksi (MPa) | Elongation in 2 in. or 50 mm or 4D, min, % |
| UNS N08810 and UNS N08811, annealed | … | 65 (448) | 25 (172) | 30 |
ASTM B564 UNS N08810 (Incoloy 800H) Heat Treatment
1. Solution Annealing (Stabilizing Anneal):
- Temperature Range: 1120–1175 °C (2050–2150 °F)
- Cooling Method: Rapid air cooling or water quenching to avoid carbide precipitation.
- Purpose: Produces a coarse grain size, giving the alloy its higher creep and rupture strength at elevated temperatures.
2. Comparison with Incoloy 800 (N08800):
- Standard Incoloy 800 (N08800) is usually annealed at 980–1090 °C (1800–2000 °F).
- Incoloy 800H (N08810) requires the higher-temperature anneal (≥ 1100 °C) to deliberately coarsen the grain structure, which enhances creep resistance but slightly reduces room-temperature tensile strength.
Testing & Certification
- Mill Test Certificate (EN 10204 3.1 / 3.2)
- Positive Material Identification (PMI)
- Non-destructive testing: UT / PT(as required)
- Hardness & tensile test reports
- Corrosion testing available on request
As a leading manufacturer and supplier of ASTM B564 UNS N08810 weld neck flanges (Incoloy 800H), we deliver high-performance alloy flanges designed for extreme service conditions. With proven high-temperature strength, oxidation resistance, and full certification, our weld neck flanges are trusted in chemical, petrochemical, and power plant applications worldwide. Contact us today for datasheets, sizes, and pricing.
