Stainless Steel 310H Socket head cap screws
ISO 4762
Where tool access is axial, Stainless Steel 310H socket head cap screws bring controlled-carbon stainless performance for sustained hot loading into a compact head envelope. Counterbore seating and housing-thread engagement determine how the available strength is used.
- 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?
Threads · Metric
Threads · Inch
Dimension Reference
Heat Treatment
Solution annealedSolution annealing and rapid cooling retain alloying elements in solution and restore the specified corrosion-resistant condition.
What we can make in Stainless Steel 310H
Partial thread
Use where a plain grip must span the clamped components. Match the under-head length and thread length so the screw tightens the stack before its thread runout reaches the tapped hole.
Full thread
Use for shorter component stacks and varied tapped-hole depths. The longer usable thread offers adjustment, while the screw end must clear the bottom of a blind hole.
- Drive
- Internal hex socket
- Length basis
- Under head
- Thread systems
- Metric · UNC · UNF · UNJ
- Assembly
- Tapped holes · Nuts
- Final condition
- Solution annealed
- Inspection
- Thread gauges · Head and shank dimensions
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 ordered annealed or solution-treated state is retained in the lot record; forming and machining do not replace the specified thermal condition.
Finished geometry
Head geometry, bearing face, shank and thread fit are checked after the final machining and thermal operations.
Where 310H fits — and what matters
Furnaces & Heat Treatment
Retort and furnace-access coversStainless Steel 310H socket head cap screws fasten retort and furnace-access covers with axial tool access inside a head counterbore. The socket and under-head seat remain accessible for service removal. Hot dwell, thermal expansion and repeated furnace cycles set the working load.
Power & Turbines
Hot-gas access covers and inspection closuresStainless Steel 310H socket head cap screws fasten hot-gas access covers and inspection closures with axial tool access inside a head counterbore. The socket and under-head seat remain accessible for service removal. Hot dwell and start-stop expansion act on the supported or moving component.
Chemical Processing
Reformer access covers and hot-gas inspection closuresStainless Steel 310H socket head cap screws fasten reformer access covers and hot-gas inspection closures with axial tool access inside a head counterbore. The socket and under-head seat remain accessible for service removal. These parts work in the heated equipment zone, where sustained loading and thermal expansion govern their section and clearance.
Same socket head cap screw. Different material priorities.
Stainless Steel 310H material dataIncoloy 800HT
Tightly controlled carbon and Al + Ti for creep duty.
- Connection priority
- Clamp load through the cylindrical head and engaged housing thread
- 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 socket recess and the under-head seating pocket, the relevant metal temperature can differ from the process or furnace set point.
Inconel 718
Precipitation-hardened strength for compact, highly loaded connections.
- Connection priority
- Clamp load through the cylindrical head and engaged housing thread
- Strength after aging
- Machine-stock properties and final aged properties describe different states. The final heat-treatment lot and mechanical results establish the strength available in the installed part. At the socket recess and the under-head seating pocket, the relevant metal temperature can differ from the process or furnace set point.
A-286
Aged iron–nickel alloy strength for hot bolting.
- Connection priority
- Clamp load through the cylindrical head and engaged housing thread
- 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 socket recess and the under-head seating pocket, the relevant metal temperature can differ from the process or furnace set point.
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 S31009 · heat number · ordered condition
- Final-part acceptance
- Grade chemistry, supplied condition and ordered mechanical requirements.
- Dimensional record
- Thread gauges · Head and shank dimensions
- Traceability
- EN 10204 3.1 material certificate · production lot · identified packing
Build your 310H socket head cap screw enquiry
Questions about 310H socket head cap screws
What changes when the screw is stronger than the housing?
The housing thread can strip before the screw reaches its tensile capacity. The engagement depth and housing material therefore belong in the joint assessment alongside the screw’s final strength condition.