Type: UNS N08811 Seamless Pipe
Material: UNS N08811(Incoloy 800HT/WNR 1.4959)
- Pipe OD: 159MM; WT: 18MM
Standard: ASTM B407
Length: Normally fixed length 6m, can as per customer’s requirement.
End: Beveled End,Plain End
What is UNS N08811 pipe?
UNS N08811 pipe refers to pipes made from Incoloy 800HT (UNS N08811). These pipes would be used in applications where the corrosion resistance and high-temperature capabilities of Incoloy 800HT are required. UNS N08811 is a high-temperature alloy that belongs to the family of nickel-iron-chromium alloys. It is often referred to as Incoloy 800HT, where “Incoloy” is a trademark of Special Metals Corporation, and “800HT” indicates the high-temperature version of the alloy. The UNS (Unified Numbering System) designation N08811 is used to identify this specific grade. Incoloy 800HT (UNS N08811) is known for its excellent resistance to high-temperature oxidation, carburization, and nitridation. It is commonly used in applications where elevated temperatures and corrosive environments are encountered, such as in heat-treating equipment, industrial furnaces, and chemical processing plants.
Equivalent Gradesof of UNS N08811: 1.4959, Incoloy 800HT, 1Cr20NiB2AlTi, X5NiCrAlT31-20.
Characteristics of Incoloy 800HT
- High temperature strength;
- High creep rupture strength;
- Resistant to oxidation and carburization in high temperature environments;
- Good corrosion resistance in many acidic environments;
- Good resistance to many sulfur-containing atmospheres.
Chemical Composition Requirements of Incoloy 800HT
|The Chemical Composition of Incoloy 800, %|
Physical Properties of Incoloy 800HT
|Density||Melting Range||Specific Heat||Electrical Resistivity|
Mechanical Properties of Incoloy 800HT
|Tensile Strength, min.||Yield Strength, min.||Elongation, min.||Hardness, min.|
The properties listed in the following table apply to the soft annealing (stabilizing annealing) of the specified specifications of Incoloy 800HT alloy. The special properties of non-standard size materials can be provided according to the requirements of specific applications.
Applications of Incoloy 800HT
- Ethylene furnace quench boilers;
- Hydrocarbon cracking;
- Valves, fittings and other components exposed to corrosive attack from 1100-1800 °F;
- Industrial furnaces;
- Heat-treating equipment;
- Chemical and petrochemical processing;
- Super-heater and re-heaters in power plants;
- Pressure vessels;
- Heat exchangers;
- Alloys 800HT are used in a variety of applications involving exposure to corrosive environments and high temperatures such as heat treating equipment,chemical and petrochemical processing, nuclear power plants and the paper pulp industry;
- Heat-treating equipment such as baskets, trays, and fixtures employ Incoloy 800HT;
- Chemical and petrochemical processing industries use the alloys for heat exchangers and other piping systems in nitric acid media especially where resistance to chloride stress-corrosion cracking is required;
- Power plants use them for super-heater and re-heater tubing.
Production chart of UNS N08811 Seamless Pipe
1. Cold Rolling (Cold drawn) Pipe Production Processes
Round Pipe Billet → Heating → Perforation → Head → Annealing → Pickling → Oil (Copper) → Multi Pass Drawing (Cold Rolling) → Billet → Heat Treatment → Straightening → Water Pressure Test → Marking → Storage
2. Hot Rolling Pipe Production Processes
Round Pipe Billet → Heating → Perforation → Three Roll Skew Rolling, Continuous Rolling or Extrusion → Off Pipe → Sizing (Or Reducing Diameter)→ Cooling → Billet → Straightening → Water Pressure Test ( Or Flaw Detection) → Marking → Storage
3. Longitudinal Welding (Straight Seam Welding) Pipe Production Processes
Including ERW, EFW.
Steel pipe wall thickness (ASME B36.10 & B36.19)
|Nominal Pipe Size||Outside diameter||Wall thickness|
|SCH 5S||SCH 10S||SCH STD (40S)||SCH XS||SCH 160S||SCH XXS|
|The dimensions are in millimeters|
|Sources : ASME B36.19, ASME B36.10|
PERMISSIBLE VARIATIONS IN OUTSIDE DIAMETERA AND WALL THICKNESS Permissible Variations In Outside Diametera And Wall Thickness
- (1) Pipe and tube having a nominal wall thickness fo 3% or less of the nominal ouside diameter. The mean outside diameter shall conform to the permissible variations of Table 3 and individual measurements (including ovality) shall conform to the plus and minus values of the table, with the values increased by 0.5% of the nominal ouside diameter.
- (2) The mean ouside diameter for pipe and tube over 4 1/2 in. (114 mm) in outside diameter with a nominal wall thickness greater than 3% of the nominal ouside diameter shall conform to the permissible variations of this table, and individual measurements shall not exceed twice the permissible variations of the table.
|Specified Outside Diameter||Permissible Variations|
|Outside||Thickness of Specified||Thickness of Specifined|
|Diameter, in (mm)||Average Wall, %||Minimum Wall, %|
|Cold-Worked Pipe and Tube:|
|0.500(13) to 5/8(16), excl||0.005(0.13)||0.005(0.13)||15||15||30||0|
|5/8(16) to 1 1/2(38), incl||0.0075(0.19)||0.0075(0.19)||10||10||20||0|
|Over 1 1/2(38) to 3 1/2(89), incl||0.010(0.25)||0.010(0.25)||10||10||22||0|
|Over 3 1/2(89) to 4 1/2(114), incl||0.015(0.38)||0.015(0.38)||10||10||22||0|
|Over 4 1/2(114) to 3 1/2(152), incl||0.020(0.51)||0.020(0.51)||12.5||12.5||25||0|
|Over 6(152) to 6 1/2(168), incl||0.25(0.64)||0.25(0.64)||12.5||12.5||25||0|
|Hot-Finished Tube A,B:|
|1 1/2(38.1) to 5 1/2(139.7), excl||0.031(0.79)||0.031(0.79)||12.5||12.5||28.5||0|
|5 1/2(139.7) to 9 1/2(234.5) incl||0.047(1.19)||0.047(1.19)||12.5||12.5||28.5||0|
- A. The wall thickness tolerances for hot-finished tubes includeseccentricity tolerance up to ±12.5%.
- B. For hot-finished 5 in. (127.0mm) and under in outside diameter, the tolerances on the ouside diameter apply for individual measurements and include ovality. For tubes over 5 in. ion outside diameter, the mean ouside diameter shall comform to the permissible variations of this table andindividual measurements shall not be twice the permissible variations for this table.
Fabrication and Heat Treatment of UNS N08811(Incoloy 800HT)
Incoloy 800HT can be machined using conventional machining methods which are used for iron based alloys. Machining operations are performed using machining coolants. High-speed operations such as grinding, turning, or milling, are performed using water-base coolants. Drilling, broaching, tapping, or boring can be performed using heavy lubricants.
Incoloy 800HT can be formed using all conventional techniques.
Incoloy 800HT is welded using shielded metal-arc welding, gas-tungsten arc welding, gas metal-arc welding, and submerged-arc welding methods.
Incoloy 800HT can be heat treated by annealing. However, it does not harden by heat treatment.
Incoloy 800HT is forged at 1010 to 1205°C (1850 to 2200°F).
Incoloy 800HT is hot worked at 872 to 1205°C (1600 to 2200°F).
Incoloy 800HT can be cold worked using standard tooling.
Incoloy 800HT is annealed at 1149°C (2100°F) followed by cooling.
Incoloy 800HT is hardened by cold working only.