Hastelloy C-22 Heavy Hex Nuts
ASME B18.2.2ASTM B574
Hastelloy C-22 heavy hex nuts pair a solid-solution nickel-chromium-molybdenum-tungsten alloy with a larger bearing face for acid exchanger, scrubber, and pump bolt systems. Paired with matching C-22 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 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
Solution annealedSolution annealing dissolves detrimental precipitates, followed by rapid cooling to preserve corrosion resistance.
What we can make in Hastelloy C-22
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 annealed
- 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
The final annealed or specified strengthened condition is linked to the lot; an aging treatment is not assumed for a solid-solution alloy.
Finished geometry
Internal thread gauging, usable engagement and bearing-face alignment are checked after final processing.
Where C-22 fits — and what matters
Acid heat exchangers & condensers
Hastelloy C-22 Heavy Hex NutsAcid-exchanger nuts can retain liquid beneath their seating faces and inside the first engaged threads. C-22 heavy hex nuts resist aggressive mixed-media exposure at these loaded interfaces. The larger nut pattern suits substantial cover studs and provides broad contact on the machined bearing surface.
Connection requirements
- Mating stud diameter, thread form, and thread class
- Nut height, width across flats, and bearing-face condition required
- Exposure chemistry, cycling duty, and heat-number certification
Scrubber towers & halide piping joints
Hastelloy C-22 Heavy Hex NutsOn scrubber flanges, wet chloride deposits can surround the nut long after exposed metal has dried. C-22 heavy hex nuts protect the internal threads and bearing face in this environment. Their substantial flats provide a practical tooling surface for planned opening of inspection covers and piping joints.
Connection requirements
- Mating stud diameter, thread form, and thread class
- Nut height, width across flats, and bearing-face condition required
- Exposure chemistry, cycling duty, and heat-number certification
Chemical transfer pump casings
Hastelloy C-22 Heavy Hex NutsChemical pump cover nuts are exposed to the same drips and washdown as the studs. A C-22 heavy hex nut avoids leaving the internally threaded component less resistant than the rest of the assembly. Its broad bearing pattern suits robust cover spotfaces where the larger nut can be reached easily.
Connection requirements
- Mating stud diameter, thread form, and thread class
- Nut height, width across flats, and bearing-face condition required
- Exposure chemistry, cycling duty, and heat-number certification
Same heavy hex nut. Different material priorities.
Hastelloy C-22 material dataHastelloy C-276 Heavy Hex Nuts
Hastelloy C-276 heavy hex nuts carry stud loads at corrosive reactor and exchanger covers. Their broad seating faces suit substantial spotfaces, and the alloy resists attack inside the loaded threads and beneath the nut. The heavy pattern is useful where maintenance tooling has adequate clearance.
Hastelloy B-3 Heavy Hex Nuts
Hastelloy B-3 heavy hex nuts suit robust reducing-acid stud assemblies where liquid can remain beneath the bearing face. Broad seating contact supports substantial cover spotfaces. B-3 offers improved thermal stability over B-2, while compatibility still depends on the absence of harmful oxidizing contamination.
Inconel 625 Heavy Hex Nuts
Inconel 625 heavy hex nuts suit substantial seawater and wet-chloride stud connections. Localized-corrosion resistance matters beneath the seating face and inside the loaded threads. The broad pattern fits robust pump spotfaces and subsea connections with sufficient clearance for the installation tooling.
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 N06022 · heat number · ordered condition
- Final-part acceptance
- Grade chemistry, supplied condition and ordered mechanical requirements.
- Dimensional record
- Thread plug gauges · Across flats · Nut height
- Traceability
- EN 10204 3.1 material certificate · production lot · identified packing
Build your C-22 heavy hex nut enquiry
Questions about C-22 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.