Hastelloy C-276 Square-head positioning bolts
ASME B18.2.1ASTM B574
Hastelloy C-276 positioning bolts separate anti-rotation at the square head from location at the shoulder. The material’s resistance to chemically aggressive, mixed process streams applies to these loaded contact surfaces as well as the thread.
- 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-276
Square head
Capture the square head in a matching slot or pocket to stop rotation while tightening from the nut side. Head width and pocket clearance determine how much turning play remains.
Locating shank
Use a machined step or shank to locate fixture plates and adjustable tooling. Specify its fit to the mating bore when repeatable position matters; thread clearance cannot provide that locating accuracy.
- Drive
- External square
- Interface
- Head flats · Shank steps
- Length basis
- Under head
- Threads
- Metric · Inch
- Final condition
- Solution annealed
- Inspection
- Head flats · Locating diameter · Step lengths · Threads
Manufacturing route
CNC machining suits samples and small lots. Cold heading or hot forging is selected for volume production according to alloy formability, head section and size.
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
Head geometry, bearing face, shank and thread fit are checked after the final machining and thermal operations.
Where C-276 fits — and what matters
Chemical Processing
Mixer drives and process-equipment bracketsHastelloy C-276 square-head positioning bolts set stops and clamp positions on mixer drives and process-equipment brackets. The square head provides tool purchase while the end face or point bears on the positioned component. Process liquid can remain at the contact after the exposed surface drains.
Pumps, Valves & OEM
Actuator mounts and pump baseplatesHastelloy C-276 square-head positioning bolts set stops and clamp positions on actuator mounts and pump baseplates. The square head provides tool purchase while the end face or point bears on the positioned component. Repeated maintenance makes fit, engagement and access part of the component specification.
Mining & Mineral Processing
Leach-equipment and dosing-skid supportsHastelloy C-276 square-head positioning bolts set stops and clamp positions on leach-equipment and dosing-skid supports. The square head provides tool purchase while the end face or point bears on the positioned component. Leach solution and deposits act on the installed part; corrosion duty is separate from abrasive wear.
Same square-head positioning bolt. Different material priorities.
Hastelloy C-276 material dataInconel 625
Solid-solution strength and resistance to aggressive process liquids.
- Connection priority
- Bearing at the locating step and reaction against the square head
- Annealed or solution-annealed 625
- The delivery condition affects strength and high-temperature response. Keep the specified condition with the component’s mechanical acceptance; 718-style aging is not the strengthening route for 625. Include liquid retained at the square-head pocket and locating shoulder in the exposure description.
Hastelloy C-22
Corrosion resistance across oxidising and reducing process exposures.
- Connection priority
- Bearing at the locating step and reaction against the square head
- 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 square-head pocket and locating shoulder in the exposure description.
Titanium Grade 2
Low mass, corrosion resistance and commercially pure titanium formability.
- Connection priority
- Bearing at the locating step and reaction against the square head
- 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 square-head pocket and locating shoulder 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 N10276 · heat number · ordered condition
- Final-part acceptance
- Grade chemistry, supplied condition and ordered mechanical requirements.
- Dimensional record
- Head flats · Locating diameter · Step lengths · Threads
- Traceability
- EN 10204 3.1 material certificate · production lot · identified packing
Build your C-276 square-head positioning bolt enquiry
Questions about C-276 square-head positioning bolts
Which tolerance should locate the component?
Use the specified shoulder or locating diameter, with a matching hole fit. Head clearance serves tool engagement or anti-rotation; it should not silently replace the drawing’s locating datum.