Hastelloy C-276 Hex socket countersunk screws
ISO 10642ASTM B574
Flush seating puts the load into the conical head of a Hastelloy C-276 countersunk screw. Resistance to chemically aggressive, mixed process streams is combined with a matching head angle and acceptance of the reduced head section.
- 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
Finished-Screw 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
Head angle & seating
90° metric and 82° inch heads need matching countersinks. Head diameter and recess depth control whether the screw sits flush.
Socket & overall length
Specify overall length including the head. Socket size and depth govern key engagement, especially in shallow head sections.
Reduced head loadability
ISO 10642 identifies reduced loadability from the countersunk head and socket geometry. For Inconel 718 or A-286, assess head capacity and seating contact alongside the specified material strength and assembly preload.
- Drive
- Internal hex socket
- Head angle
- 90° metric · 82° inch
- Length basis
- Overall, including head
- Threads
- Metric · UNC · UNF · UNJ
- Final condition
- Solution annealed
- Inspection
- Head angle & diameter · Socket size & depth · Overall length · Thread gauges
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 angle, socket depth and the head-to-shank transition are inspected with the thread; the reduced head section remains part of finished-part acceptance.
Where C-276 fits — and what matters
Chemical Processing
Process-equipment covers and shieldsHastelloy C-276 hex socket countersunk screws secure process-equipment covers and shields with the head below or flush with the surface, leaving clearance for neighbouring moving parts or removable covers. Process liquid can remain at the contact after the exposed surface drains.
Pumps, Valves & OEM
Actuator housings and removable equipment coversHastelloy C-276 hex socket countersunk screws secure actuator housings and removable equipment covers with the head below or flush with the surface, leaving clearance for neighbouring moving parts or removable covers. Repeated maintenance makes fit, engagement and access part of the component specification.
Mining & Mineral Processing
Chemical-recovery equipment shieldsHastelloy C-276 hex socket countersunk screws secure chemical-recovery equipment shields with the head below or flush with the surface, leaving clearance for neighbouring moving parts or removable covers. Leach solution and deposits act on the installed part; corrosion duty is separate from abrasive wear.
Same hex socket countersunk screw. Different material priorities.
Hastelloy C-276 material dataInconel 625
Solid-solution strength and resistance to aggressive process liquids.
- Connection priority
- Head-bearing stress in the reduced countersunk section
- 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 conical seat and recessed socket in the exposure description.
Hastelloy C-22
Corrosion resistance across oxidising and reducing process exposures.
- Connection priority
- Head-bearing stress in the reduced countersunk section
- 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 conical seat and recessed socket in the exposure description.
Titanium Grade 2
Low mass, corrosion resistance and commercially pure titanium formability.
- Connection priority
- Head-bearing stress in the reduced countersunk section
- 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 conical seat and recessed socket 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 angle & diameter · Socket size & depth · Overall length · Thread gauges
- Traceability
- EN 10204 3.1 material certificate · production lot · identified packing
Build your C-276 hex socket countersunk screw enquiry
Questions about C-276 hex socket countersunk screws
Does a high-strength alloy remove countersunk-head loadability limits?
The conical head and socket still reduce the available section. Head-bearing stress, countersink contact and housing thread engagement need assessment alongside the final alloy strength.