
Incoloy 800 Tall flange nuts
ISO 4161ASTM B408
A tall Incoloy 800 flange nut extends the usable thread envelope and spreads the seating load. The grade brings heat and oxidation resistance for thermal equipment, while engagement depth and flange contact determine the assembled fit.
- MOQ
- 100PCS
- Samples · typical
- ~20 days
- Production · typical
- 25–35 days
- Heat treatment
- Annealed
EN 10204 3.1 MTC + heat-number traceability
Which standard is on your order?
Raw Material Specifications
Threads · Metric
Threads · Inch
Dimension Reference
Heat Treatment
AnnealedAnnealing reduces work hardening and restores ductility for the specified supplied condition.
What we can make in Alloy 800
Body height: regular / tall
- Regular height
- Fits compact equipment covers and mounting brackets where clearance above the nut is limited.
- Tall body
- Provides longer thread engagement on clamping studs in jigs, fixtures and machine-tool setups that are tightened and released repeatedly.
Bearing face: plain / serrated
- Plain face
- For painted covers and finished equipment faces where serration marks are unwanted.
- Serrated face
- For metal mounting brackets where teeth can bite directly into the seat to resist rotation.
All configurations shown are available on request.
- Body
- Extended height
- Bearing
- Integral flange
- Threads
- Metric · Inch
- Key dimensions
- Height · Flange diameter · Across flats
- Final condition
- Annealed
- Inspection
- Height · Flange diameter · Thread engagement · Gauging
Manufacturing route
Small lots use machined blanks. Volume nut blanks use a forming route compatible with the alloy before machining the bore and tapping.
Heat treatment & final condition
The ordered annealed or solution-treated state is retained in the lot record; forming and machining do not replace the specified thermal condition.
Finished geometry
Internal thread gauging, usable engagement and bearing-face alignment are checked after final processing.
Where 800 fits — and what matters

Furnaces & Heat Treatment
Heat-treatment fixturesIncoloy 800 tall flange nuts retain the threaded connections on heat-treatment fixtures, combining increased nut height with an integral bearing flange. Hot dwell, thermal expansion and repeated furnace cycles set the working load.

Power & Turbines
Boiler-duct supports and hot auxiliary bracketsIncoloy 800 tall flange nuts retain the threaded connections on boiler-duct supports and hot auxiliary brackets, combining increased nut height with an integral bearing flange. Hot dwell and start-stop expansion act on the supported or moving component.

Chemical Processing
Reformer tube-support and heater fixturesIncoloy 800 tall flange nuts retain the threaded connections on reformer tube-support and heater fixtures, combining increased nut height with an integral bearing flange. These parts work in the heated equipment zone, where sustained loading and thermal expansion govern their section and clearance.
Same tall flange nut. Different material priorities.
Incoloy 800 material dataIncoloy 800
UNS N08800 · Current grade- Carbon
- ≤0.10%
- What changes
- General heat and oxidation resistance; no grain-size requirement in the family comparison.
Incoloy 800H
UNS N08810- Carbon
- 0.05–0.10%
- What changes
- Controlled carbon and coarse-grain condition for creep and stress-rupture duty.
Incoloy 800HT
UNS N08811- Carbon
- 0.06–0.10%
- What changes
- Tighter carbon and Al + Ti control (0.85–1.20%), with solution treatment and coarse grain for creep duty.
From drawing to documented delivery




- 01Drawing & BOMForm, dimensions and quantity
- 02Material & formingGrade, heat and manufacturing route
- 03Final inspectionGeometry, threads and ordered tests
- 04Documents & dispatchLot records and identified packing
Order documents
- Material identity
- UNS N08800 · heat number · ordered condition
- Final-part acceptance
- Grade chemistry, supplied condition and ordered mechanical requirements.
- Dimensional record
- Height · Flange diameter · Thread engagement · Gauging
- Traceability
- EN 10204 3.1 material certificate · production lot · identified packing
Build your 800 tall flange nut enquiry
Questions about 800 tall flange nuts
Does greater nut height automatically increase joint capacity?
Capacity depends on the engaged threads, nut condition and stud strength, as well as load distribution. Extra unengaged height does not add thread engagement and does not create prevailing torque.