A-286 12-Point Flange Bolts
ASME B18.2.5M · component drawingASTM A638 — bar / forgings
A-286 12-point flange bolts for compact hot-equipment connections, combining an aged high-strength alloy with a small external drive and integral bearing surface.
- MOQ
- 100PCS
- Samples · typical
- ~20 days
- Production · typical
- 25–35 days
- Heat treatment
- Solution treated and aged
EN 10204 3.1 MTC + heat-number traceability
A-286 in this connection
An iron-based precipitation-hardening alloy for high-strength connections operating at elevated temperature.
- Connection
- Turbine auxiliary housings & hot casing connections
- Critical dimensions
- Wrenching size · flange diameter · under-head radius
Which standard is on your order?
Raw Material Specifications
Finished-Bolt Specifications
Threads · Metric
Threads · Inch
Dimension Reference
Heat Treatment
Solution treated and agedSolution treatment is followed by precipitation aging, with the Grade 660 class defining the required heat-treatment route and final properties.
What we can make in A-286
Forms & dimension guide
Fully threaded / Partially threaded
The difference is the plain shank. Fully threaded bolts have threads along the shank up to the head transition; partially threaded bolts retain an unthreaded grip section beneath the flange.
External head / Internal recess
The difference is where the tool engages. An external 12-point head is gripped around its outside by a matching socket. An internal spline recess is driven by a bit inserted into the head. These are different drive structures and should not be specified interchangeably.
- Product forms
- Metric 12-point pattern · Inch drawing pattern
- Dimensional control
- Wrenching size · flange diameter · under-head radius
- Manufacturing
- CNC-machine short runs; form production blanks by the selected heading or forging route. Finish the double-hex drive, bearing flange and threads to the equipment drawing.
- Final condition
- Solution treatment and aging are tied to the ordered class and strength, with the heat-treatment lot traceable to the fasteners.
- Inspection
- Heat-treatment class · tensile / hardness · specified stress-rupture tests
Where A-286 fits — and what matters
Power & Turbines
Boiler-duct supports and hot auxiliary bracketsA-286 12-point flange bolts fasten boiler-duct supports and hot auxiliary brackets where a 12-point socket gives useful indexing around restricted equipment access. The flange supports the loaded head seat. Hot dwell and start-stop expansion act on the supported or moving component.
Furnaces & Heat Treatment
Heat-treatment fixturesA-286 12-point flange bolts fasten heat-treatment fixtures where a 12-point socket gives useful indexing around restricted equipment access. The flange supports the loaded head seat. Hot dwell, thermal expansion and repeated furnace cycles set the working load.
Chemical Processing
Reformer tube-support and heater fixturesA-286 12-point flange bolts fasten reformer tube-support and heater fixtures where a 12-point socket gives useful indexing around restricted equipment access. The flange supports the loaded head seat. These parts work in the heated equipment zone, where sustained loading and thermal expansion govern their section and clearance.
Same 12-point flange bolt. Different material priorities.
A-286 material dataInconel 718
Precipitation hardening gives 718 its high strength; its specified condition is central to loaded and hot-service joints.
Inconel 718 12-Point Flange BoltsInconel 625
Molybdenum and niobium provide solid-solution strength, combined with resistance to chloride pitting and crevice corrosion.
Inconel 625 12-Point Flange Bolts310S
High chromium and nickel support oxidation resistance in furnace atmospheres; long loaded service also depends on creep behaviour.
310S 12-Point Flange BoltsFrom drawing to documented delivery
- 01Drawing & BOMGrade, condition and part dimensions
- 02Sample lotOptional · typically ~20 days
- 03Production & testingTypically 25–35 days
- 04Documents & dispatchHeat-linked lots and packing
Connection & acceptance
Turbine auxiliary housings & hot casing connections: Temperature cycles · preload · specified heat-treatment class.
Material & final condition
Solution treatment and aging are tied to the ordered class and strength, with the heat-treatment lot traceable to the fasteners.
Connection inspection
Wrenching size · flange diameter · under-head radius. Heat-treatment class · tensile / hardness · specified stress-rupture tests.
Build your A-286 12-point flange bolt enquiry
Upload drawing insteadQuestions about A-286 12-point flange bolts
What does Grade 660 add to an A-286 bolt callout?
ASTM A453 Grade 660 defines bolting requirements with distinct classes and heat-treatment routes. The class and mechanical acceptance belong alongside the drawing; A-286 alone does not select them.
Technical references & photo credits
Catalogue photography shows product form. Application examples connect alloy properties to equipment duties; they are not customer installation records. Quantities, schedules and the inspection scope are confirmed in the quotation.