UNS N07718 · W.Nr. 2.4668

Inconel 718 Slotted & castle nuts

DIN 935-1ASTM B637

Inconel 718 castle and slotted nuts combine precipitation-hardened strength for compact, highly loaded connections 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
Solution treated / solution treated and aged

EN 10204 3.1 MTC + heat-number traceability

Upload drawing
Other alloys800HTA-286310S

Which standard is on your order?

Raw Material Specifications

Threads · Metric

Threads · Inch

Dimension Reference

Heat Treatment

Solution treated; aged when specified

Solution treatment prepares 718 for forming or machining, and subsequent aging develops the strength required by the ordered condition.

What we can make in Alloy 718

Slotted nut: slots in hex body

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: slots in reduced crown

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.

Split pin through nut slots and bolt cross-hole

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
Solution treated · solution treated and aged
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

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 718 fits — and what matters

Heat-treatment workshop with horizontal furnaces, green pipes and a blue motor

Furnaces & Heat Treatment

Fixture pivots and conveyor shafts

Inconel 718 slotted & castle nuts retain fixture pivots and conveyor shafts with a split pin through the nut slots and a cross-drilled shaft. Slot alignment establishes the final positive-retention position. Hot dwell, thermal expansion and repeated furnace cycles set the working load.

Cross-hole position · slot alignment · split pin
Furnaces & Heat Treatment fasteners
Technician inspecting blade rows beneath a large turbine rotor

Power & Turbines

Hot-duct linkage pins and damper spindles

Inconel 718 slotted & castle nuts retain hot-duct linkage pins and damper spindles with a split pin through the nut slots and a cross-drilled shaft. Slot alignment establishes the final positive-retention position. Hot dwell and start-stop expansion act on the supported or moving component.

Cross-hole position · slot alignment · split pin
Power & Turbines fasteners
Silver distillation columns with access ladders and yellow service platforms

Chemical Processing

Reformer support pins and heater-fixture rods

Inconel 718 slotted & castle nuts retain reformer support pins and heater-fixture rods with a split pin through the nut slots and a cross-drilled shaft. Slot alignment establishes the final positive-retention position. These parts work in the heated equipment zone, where sustained loading and thermal expansion govern their section and clearance.

Cross-hole position · slot alignment · split pin
Chemical Processing fasteners

Same slotted & castle nut. Different material priorities.

Inconel 718 material data
UNS N08811

Incoloy 800HT

Tightly controlled carbon and Al + Ti for creep duty.

Connection priority
Nut preload with separate positive pin retention
N08811 material control
800HT tightens the 800-family chemistry around creep performance. Its solution-treated, coarse-grain condition and N08811 identity should remain linked through forming and final acceptance. At the pin slots, cross-drilled shaft and bearing face, the relevant metal temperature can differ from the process or furnace set point.
Incoloy 800HT slotted & castle nuts
UNS S66286

A-286

Aged iron–nickel alloy strength for hot bolting.

Connection priority
Nut preload with separate positive pin retention
Grade 660 class
An ASTM A453 Grade 660 order includes its class and corresponding processing requirements. The alloy name A-286 alone does not identify that acceptance condition. At the pin slots, cross-drilled shaft and bearing face, the relevant metal temperature can differ from the process or furnace set point.
A-286 slotted & castle nuts
UNS S31008

310S

Low-carbon heat resistance in oxidation-exposed equipment.

Connection priority
Nut preload with separate positive pin retention
310S is not 310H
S31008 is the low-carbon grade. For a component under sustained hot load, distinguish that specification from the controlled-carbon creep purpose of S31009. At the pin slots, cross-drilled shaft and bearing face, the relevant metal temperature can differ from the process or furnace set point.
310S slotted & castle nuts

From drawing to documented delivery

Heat treatment
Heat treatment
CNC machining
CNC machining
Rockwell hardness testing
Rockwell hardness testing
Wooden-crate packing
Wooden-crate packing
  1. 01Drawing & BOMForm, dimensions and quantity
  2. 02Material & formingGrade, heat and manufacturing route
  3. 03Final inspectionGeometry, threads and ordered tests
  4. 04Documents & dispatchLot records and identified packing

Order documents

Material identity
UNS N07718 · heat number · ordered condition
Final-part acceptance
Lot-linked aging record and mechanical acceptance in the final condition.
Dimensional record
Slot width · Crown height · Pin clearance · Threads
Traceability
EN 10204 3.1 material certificate · production lot · identified packing

Build your 718 slotted & castle nut enquiry

QUOTE LIST ITEMInconel 718 slotted & castle nuts; UNS N07718; Slotted hex nut

Questions about 718 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.

Technical references & photo credits