Monel K-500 Heavy Hex Nuts
ASME B18.2.2ASTM B865
Monel K-500 heavy hex nuts pair an age-hardened nickel-copper alloy with a larger bearing face for high-load marine and pump bolt systems. Paired with matching K-500 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
- Annealed / age hardened
EN 10204 3.1 MTC + heat-number traceability
Which standard is on your order?
Raw Material Specifications
Finished-Nut Specifications
Threads · Metric
Threads · Inch
Dimension Reference
Heat Treatment
Annealed or age hardenedAnnealing provides a workable starting condition, while controlled aging develops the higher strength specified for age-hardened K-500.
What we can make in Monel K-500
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
- Annealed · age hardened
- 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 K-500 fits — and what matters
Seawater pumps
Monel K-500 Heavy Hex NutsPump-casing studs need nuts capable of carrying their tensile load, not just matching their corrosion resistance. K-500 heavy hex nuts pair a stronger nickel-copper material with a wider bearing footprint and larger wrenching flats. That combination is useful on seawater pump covers with room for heavy-pattern nuts.
Connection requirements
- Mating bolt/stud diameter, thread form, and thread class
- Nut height, width across flats, and bearing-face condition required
- Seawater exposure, age-hardened condition, and heat-number certification
Marine valve bonnets
Monel K-500 Heavy Hex NutsMarine bonnet joints often leave only the nut accessible during servicing. The heavy hex pattern provides substantial wrench engagement, while age-hardened K-500 offers strength for a matched stud-and-nut assembly. Checking nut proof load alongside the stud specification makes the connection's load capacity explicit.
Connection requirements
- Mating stud diameter, thread form, and thread class
- Nut height, width across flats, and bearing-face condition required
- Chloride exposure, age-hardened condition, and heat-number certification
Split-case & multistage pump casings
Monel K-500 Heavy Hex NutsOn a split seawater-pump casing, K-500 heavy hex nuts can support a high-strength stud assembly while spreading its bearing load over a substantial spotface. The larger pattern is useful where the casing has enough seating area and socket clearance. Specify the nut capacity with the chosen stud condition.
Connection requirements
- Mating stud diameter, thread form, and thread class
- Nut height, width across flats, and bearing-face condition required
- Seawater exposure, age-hardened condition, and heat-number certification
Same heavy hex nut. Different material priorities.
Monel K-500 material dataInconel 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.
Inconel 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.
Hastelloy 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.
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 N05500 · 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 K-500 heavy hex nut enquiry
Questions about K-500 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.