Incoloy 800HT Long-shank hex head bolts
ISO 4014ASTM B408
Incoloy 800HT long-shank hex bolts carry the grip through a plain section while providing tightly controlled carbon and Al + Ti for creep duty. Grip length and thread runout locate the loaded interfaces along the extended shank.
- MOQ
- 100PCS
- Samples · typical
- ~20 days
- Production · typical
- 25–35 days
- Heat treatment
- Solution annealed (≥1149°C / 2100°F)
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
Solution annealedThe specified solution treatment develops the controlled grain structure needed for sustained high-temperature creep duty.
What we can make in Alloy 800HT
Plain grip section
Use across thick equipment flanges, spacers and mounting stacks where the grip requires a continuous plain shank. The grip length keeps the threaded transition beyond the intended bearing or shear section.
Threaded end
Allow enough usable thread beyond the stack for the nut, washer and tightening travel. Too little thread can leave the nut bottomed on the plain shank before the joint is clamped.
Long shank vs shoulder screw
For a pivot or locating bore, specify the actual shank diameter tolerance and surface finish. A long-shank bolt provides grip length; a shoulder-screw fit requires separate control of the locating surface.
- Head
- External hex
- Shank
- Extended plain length
- Length basis
- Under head
- Threads
- Metric · UNC · UNF · UNJ
- Final condition
- Solution annealed (≥1149°C / 2100°F)
- Inspection
- Thread gauges · Head and shank dimensions
Manufacturing route
CNC machining suits samples and small lots. Cold heading or hot forging is selected for volume production according to alloy formability, head section and size.
Heat treatment & final condition
Solution annealing at a minimum of 1149°C (2100°F) establishes the coarse-grain condition used for creep resistance. The heat-treatment record and grain-size result identify this delivery state.
Finished geometry
Head geometry, bearing face, shank and thread fit are checked after the final machining and thermal operations.
Where 800HT fits — and what matters
Furnaces & Heat Treatment
Heat-treatment fixturesIncoloy 800HT long-shank hex head bolts pass through the deeper grip of heat-treatment fixtures; the extended plain shank locates the joint before the nut takes up the thread. Hot dwell, thermal expansion and repeated furnace cycles set the working load.
Power & Turbines
Boiler-duct supports and hot auxiliary bracketsIncoloy 800HT long-shank hex head bolts pass through the deeper grip of boiler-duct supports and hot auxiliary brackets; the extended plain shank locates the joint before the nut takes up the thread. Hot dwell and start-stop expansion act on the supported or moving component.
Chemical Processing
Reformer tube-support and heater fixturesIncoloy 800HT long-shank hex head bolts pass through the deeper grip of reformer tube-support and heater fixtures; the extended plain shank locates the joint before the nut takes up the thread. These parts work in the heated equipment zone, where sustained loading and thermal expansion govern their section and clearance.
Same long-shank hex head bolt. Different material priorities.
Incoloy 800HT material dataIncoloy 800
UNS N08800- 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 · Current grade- 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 N08811 · heat number · ordered condition
- Final-part acceptance
- UNS grade, carbon and alloy chemistry, solution-treatment record and ordered grain-size evidence.
- Dimensional record
- Thread gauges · Head and shank dimensions
- Traceability
- EN 10204 3.1 material certificate · production lot · identified packing
Build your 800HT long-shank hex head bolt enquiry
Questions about 800HT long-shank hex head bolts
Why is total length insufficient for a long-shank bolt?
Two bolts of the same total length can put the thread runout in different places. The joint needs a defined grip length so its bearing or shear interface meets the intended shank section.