Nimonic 80A Heavy Hex Nuts
ASME B18.2.2ASTM B637
Nimonic 80A heavy hex nuts pair a precipitation-hardened nickel-chromium alloy with a larger bearing face for high-load turbine, steam, and exhaust bolt systems. Paired with matching 80A bolts and studs, they distribute bearing load and support full thread engagement.
- MOQ
- 100PCS
- Samples · typical
- ~20 days
- Production · typical
- 25–35 days
- Heat treatment
- Solution treated and aged
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 treated and agedSolution treatment prepares the alloy for controlled precipitation aging, which develops the strength of the ordered condition.
What we can make in Nimonic 80A
Regular hex
Use on equipment covers and mounting brackets with standard socket access. The compact wrenching envelope is useful where adjacent fasteners or housing walls restrict tool clearance.
Heavy hex
Use on flange-bolting sets and pressure-equipment joints calling for a heavy-hex pattern. The wider bearing footprint and larger wrench size require more seat area and socket clearance than a regular hex nut.
Thin hex
Use in restricted axial spaces or as part of a specified two-nut locking arrangement. Reduced thread engagement means a thin nut is not a direct load-capacity replacement for a full-height nut.
- Metric thread
- M4–M100
- Inch thread
- 1/4″–4″
- Patterns
- Heavy hex
- Thread systems
- Metric · UNC · UNF · 8UN · UNJ
- Final condition
- Solution treated and aged
- Inspection
- Thread plug gauges · Across flats · Nut height
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
Solution treatment and the specified aging condition are recorded against the production lot; final dimensions are checked after thermal processing.
Finished geometry
Internal thread gauging, usable engagement and bearing-face alignment are checked after final processing.
Where Nimonic 80A fits — and what matters
Gas & steam turbine casing joints
Nimonic 80A Heavy Hex NutsA hot turbine stud needs a nut capable of carrying its load in the specified material condition. Nimonic 80A heavy hex nuts provide a broad bearing pattern in a precipitation-hardened alloy. Their substantial flats support controlled assembly where the casing geometry allows adequate socket clearance.
Connection requirements
- Mating stud diameter, thread form, and thread class
- Nut height, width across flats, and bearing-face condition required
- Temperature range, cycling duty, and heat-number certification
High-pressure steam valve bonnets
Nimonic 80A Heavy Hex NutsAt steam-valve bonnet studs, 80A heavy hex nuts transfer load into the cover spotfaces. The large pattern contributes bearing area and wrench engagement; the alloy and heat treatment contribute hot strength. Nut proof load is specified alongside the mating stud, so the assembled connection has a coherent load basis.
Connection requirements
- Mating stud diameter, thread form, and thread class
- Nut height, width across flats, and bearing-face condition required
- Temperature range, cycling duty, and heat-number certification
Exhaust manifolds & expansion bellows
Nimonic 80A Heavy Hex NutsNimonic 80A heavy hex nuts suit substantial exhaust-flange studs where the required hot load justifies an aged alloy. Their broad seat fits a robust flange face, and the larger flats provide room for controlled tightening where the pipework allows socket access.
Connection requirements
- Mating stud diameter, thread form, and thread class
- Nut height, width across flats, and bearing-face condition required
- Temperature range, vibration duty, and heat-number certification
Same heavy hex nut. Different material priorities.
Nimonic 80A material dataInconel 718 Heavy Hex Nuts
High-load turbine casing and hot-valve studs transfer their tension through the nut into the cover. Inconel 718 heavy hex nuts combine precipitation-hardened strength with the bearing area of a heavy pattern. Broad flats provide substantial socket engagement on these loaded, serviceable connections.
Inconel X-750 Heavy Hex Nuts
On a hot casing or valve cover, Inconel X-750 heavy hex nuts transfer sustained stud loads into a substantial seating face. Their precipitation-treated condition supplies hot-strength properties, and the heavy pattern adds wrench engagement for assembly tooling. Nut condition and proof load are paired with the mating stud's requirements.
Nimonic 75 Heavy Hex Nuts
Nimonic 75 heavy hex nuts pair oxidation resistance with broad bearing faces for moderately loaded furnace supports and retort accessories. Large flats suit substantial maintenance tooling. The heavy pattern is useful where the support plate has sufficient bearing area and socket clearance.
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 N07080 · heat number · ordered condition
- Final-part acceptance
- Lot-linked aging record and mechanical acceptance in the final condition.
- Dimensional record
- Thread plug gauges · Across flats · Nut height
- Traceability
- EN 10204 3.1 material certificate · production lot · identified packing
Build your Nimonic 80A heavy hex nut enquiry
Questions about Nimonic 80A hex nuts
Does a matching UNS make the stud and nut a matched set?
Matching chemistry addresses only one part of the order. Nut strength, effective engagement, internal thread fit and surface friction must also suit the stud and assembly tightening method.