
Inconel 625 Slotted & castle nuts
DIN 935-1ASTM B446
Inconel 625 castle and slotted nuts combine solid-solution strength and resistance to aggressive process liquids with visible pin retention. The cross-hole, pin and nut slots complete the system; the nut’s material condition governs its loaded thread.
- MOQ
- 100PCS
- Samples · typical
- ~20 days
- Production · typical
- 25–35 days
- Heat treatment
- Annealed / 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
Annealed or solution annealedFor B446 stock, Grade 1 is annealed and Grade 2 is solution annealed; the higher-temperature solution treatment supports creep resistance rather than age hardening.
What we can make in Alloy 625
Slotted nut
Use on drilled shafts and pins where a cotter pin retains the nut after adjustment. Slots in the hex body provide a lower axial envelope when the installation has limited clearance.
Castle nut
Use the raised slotted crown to position the cotter-pin path above the wrenching body. The crown needs clearance beyond the bearing assembly or linkage end.
Pin alignment
For wheel, pivot and linkage assemblies, align the slots with the cross-hole using the assembly’s preload or end-play procedure. The pin retains the nut; it does not set the bearing adjustment.
- Retention
- Slots · Split pin
- Mating part
- Cross-drilled bolt or shaft
- Patterns
- Slotted · Castellated
- Threads
- Metric · Inch
- Final condition
- Annealed · solution annealed
- Inspection
- Slot width · Crown height · Pin clearance · Threads
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 625 fits — and what matters

Chemical Processing
Pump shafts and mixer-drive partsInconel 625 slotted & castle nuts retain pump shafts and mixer-drive parts with a split pin through the nut slots and a cross-drilled shaft. Slot alignment establishes the final positive-retention position. Process liquid can remain at the contact after the exposed surface drains.

Pumps, Valves & OEM
Valve stems and pump-drive collarsInconel 625 slotted & castle nuts retain valve stems and pump-drive collars with a split pin through the nut slots and a cross-drilled shaft. Slot alignment establishes the final positive-retention position. Repeated maintenance makes fit, engagement and access part of the component specification.

Mining & Mineral Processing
Dosing-pump shafts and agitator-drive partsInconel 625 slotted & castle nuts retain dosing-pump shafts and agitator-drive parts with a split pin through the nut slots and a cross-drilled shaft. Slot alignment establishes the final positive-retention position. Leach solution and deposits act on the installed part; corrosion duty is separate from abrasive wear.
Same slotted & castle nut. Different material priorities.
Inconel 625 material dataHastelloy C-276
Resistance to chemically aggressive, mixed process streams.
- Connection priority
- Nut preload with separate positive pin retention
- Process liquid and shutdown chemistry
- C-276 is selected for its nickel–chromium–molybdenum–tungsten chemistry. Residual product, cleaning liquid and oxidising contamination can expose a sheltered connection differently from the main flow. Include liquid retained at the pin slots, cross-drilled shaft and bearing face in the exposure description.
Hastelloy C-22
Corrosion resistance across oxidising and reducing process exposures.
- Connection priority
- Nut preload with separate positive pin retention
- Production and cleaning cycles
- C-22’s chromium-bearing chemistry is relevant when chemical exposure changes between operating and cleaning cycles. Include both liquids when comparing it with C-276 or a B-type nickel alloy. Include liquid retained at the pin slots, cross-drilled shaft and bearing face in the exposure description.
Titanium Grade 2
Low mass, corrosion resistance and commercially pure titanium formability.
- Connection priority
- Nut preload with separate positive pin retention
- Commercially pure titanium
- Grade 2 favours corrosion resistance and forming characteristics over the higher strength of Grade 5. Mating-metal contact, surface condition and assembly friction remain part of the connection design. Include liquid retained at the pin slots, cross-drilled shaft and bearing face in the exposure description.
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 N06625 · heat number · ordered condition
- Final-part acceptance
- Grade chemistry, supplied condition and ordered mechanical requirements.
- Dimensional record
- Slot width · Crown height · Pin clearance · Threads
- Traceability
- EN 10204 3.1 material certificate · production lot · identified packing
Build your 625 slotted & castle nut enquiry
Questions about 625 slotted & castle nuts
What must be specified with a castle nut?
The cross-drilled shaft, retaining pin material and slot geometry complete the retention system. Slot alignment follows the assembly tightening procedure; the pin does not generate the joint’s clamp load.