Specifications
Surface Treatments
Certifications
- ISO 9001 - 2015 Certified
- PED 2014/68/EC
- NACE MR0175/ISO 15156-2
- NORSOK M-650
- DFAR
- MERKBLATT AD 2000 W2/W7/W10
A286 Forged Bar
A286 forged bar is heavy-section A286 bar produced by open-die or closed-die hot forging from VIM-VAR ingot — used for diameters and section sizes beyond practical hot-rolling capability (typically > 200 mm). TorqBolt manufactures A286 forged bar to AMS 5731 / 5732, ASTM A638 grade 660 Type 1 / Type 2 (the canonical forged A286 spec), ASTM A453 grade 660, and ASTM B637 standards in 75-300 mm round and rectangular sections. Forged bar offers superior grain-flow continuity and isotropic mechanical properties vs hot-rolled bar of the same size. Heat-treated to deliver 130 ksi tensile / 95 ksi yield, with the homogeneous microstructure required for ASME III nuclear, ASTM A638 forging-grade applications. See parent A286 bar stock, sister variants round bar, hex bar, A286 forgings, and the canonical chemical composition, heat treatment.
About A286 Forged Bar
A286 forged bar is produced by open-die or closed-die hot forging from VIM-VAR ingot at 1095-1150 °C. Open-die forging uses flat dies on a hydraulic press to progressively reduce ingot to bar — controlled grain flow and superior isotropic mechanical properties result. Closed-die forging is used for larger production volumes of standard sizes. Forged bar is the canonical raw stock for ASTM A638 grade 660 forgings — the spec covers solution-treated and aged A286 in forged condition for high-temperature pressure-bearing service. Distinguished from hot-rolled round bar by the forging-grade microstructure with improved grain flow continuity and reduced macroscopic segregation. Each forged-bar lot is post-forging solution-treated 1650-1800 °F, aged 1325 °F × 16 h, ultrasonically tested per ASTM A388, and ships with EN 10204 3.1 mill cert (3.2 third-party-witness available).
A286 Forged Bar Production & Standards
TorqBolt produces A286 forged bar in three primary forging conditions:
- Open-die hot-forged round bar (ASTM A638 Type 1) — Open-die forged at 1095-1150 °C, sol-treated 1650 °F, aged 1325 °F. ASTM A638 Type 1 covers higher room-temperature tensile strength variant. Diameters 75-300 mm.
- Open-die hot-forged round bar (ASTM A638 Type 2) — Forged + sol-treated 1800 °F + aged 1325 °F. ASTM A638 Type 2 covers higher stress-rupture-strength variant for sustained 1100-1300 °F service. Diameters 75-300 mm.
- Closed-die hot-forged (precision profiles) — Closed-die forging for tighter near-net-shape dimensions — used for production volumes of standard rectangular and stepped-cross-section forged bar.
- AMS 5731 / 5732 wrought + forged condition — AMS 5731 covers sol-treated bar / forging / tubing / rings; AMS 5732 covers sol-treated and aged. Both apply to forged bar in addition to wrought bar.
- Custom large-section forged bar — Custom sizes 300-500 mm in round or rectangular cross-section — open-die forged to drawing for nuclear pressure-vessel and industrial heavy-machinery applications.
A286 Forged Bar Sizes & Specifications
| Diameter / Section | Forging condition | ASTM A638 type | Tolerance | Typical use |
|---|---|---|---|---|
| 75-100 mm round | Open-die | Type 1 or 2 | +3.0 / -0 mm | Aerospace shafting |
| 101-150 mm round | Open-die | Type 1 or 2 | +5.0 / -0 mm | Gas-turbine accessory shafts |
| 151-200 mm round | Open-die | Type 1 or 2 | +7.0 / -0 mm | Industrial machinery shafting |
| 201-250 mm round | Open-die | Type 1 or 2 | +10 / -0 mm | Nuclear reactor internals |
| 251-300 mm round | Open-die | Type 1 or 2 | +12 / -0 mm | Pressure-vessel structural |
| 50 × 200 mm rect. | Open-die | Type 1 or 2 | +5.0 × +5.0 mm | Heavy structural reinforcement |
| 100 × 300 mm rect. | Open-die | Type 1 or 2 | +7.0 × +7.0 mm | Pressure-vessel cladding |
| Custom / drawing | Open or closed die | Per spec | Per drawing | Special applications |
A286 Forged Bar Manufacturing Process
Every a286 forged bar TorqBolt ships traces back to a vacuum-induction-melted plus vacuum-arc-remelted (VIM-VAR) ingot meeting AMS 5731 / 5732 chemistry. The complete process route:
- VIM-VAR ingot input: Vacuum-induction-melted + vacuum-arc-remelted ingot to AMS 5731 / 5732 / ASTM A638 chemistry. Aerospace lots use double-melted (VIM + VAR) for inclusion control.
- Ingot reheat: Ingot heated to 1095-1150 °C for forging start. Soak time 1-2 hours per inch of section to ensure uniform temperature throughout.
- Open-die hot forging: Hydraulic press with flat dies — progressive reduction of ingot to bar over multiple heats. Typical reduction ratio 4:1 to 6:1. Re-heat between passes if needed (forging finishes ≥ 925 °C).
- Cogging / cross-rolling: Bar progressively reduced through cross-rolling passes to break up cast structure and achieve uniform grain flow continuity.
- Pickling + surface inspection: Forged bar pickled in HNO₃ + HF, surface inspected per ASTM E45 inclusion rating + 100 % visual.
- Solution treatment: Vacuum or atmosphere furnace 1650 °F (Type 1) or 1800 °F (Type 2). 1 h per inch of section, oil-quench.
- Precipitation aging: 1325 °F for 16 hours, air-cool. Hardness 29-32 HRC.
- Ultrasonic inspection (UT): 100 % UT per ASTM A388 / SE-388 — internal-flaw detection critical for forged-grade aerospace and nuclear applications.
- Cut to length + label: Bar cut to drawing length, end-faced, ultrasonic test report attached, heat-traceability labelled.
A286 Forged Bar Inspection & Certification
Each lot ships with a signed inspection certificate. Aerospace orders default to AS9100D first-article reporting per AS9102. Industrial orders default to EN 10204 type 3.1; sour-service and offshore step up to type 3.2 with third-party witness. Inspection scope:
- Diameter and section dimensions verified per ASTM A638 tolerance.
- Surface inspection 100 % visual for laps, seams, forging defects per ASTM E45.
- Macrostructure check — etch a transverse slice from each heat per ASTM E381.
- Ultrasonic inspection 100 % per ASTM A388 / SE-388 — Class 1 acceptance for aerospace and nuclear lots.
- Hardness sample 4 positions per heat per ASTM E384.
- Tensile coupon from each heat per ASTM E8 + elevated-temperature per E21.
- Charpy V-notch impact test per ASTM E23 — required for nuclear and cryogenic-service forged bar.
- Magnetic permeability < 1.005 per ASTM A342.
- AS9102 first-article on aerospace heats; EN 10204 3.2 third-party witness for nuclear and offshore.
A286 Forged Bar Downstream Forming & Machining
Forged bar is raw stock — torque does not apply directly. Downstream forging into closed-die parts: forging force per square inch of die-contact area typically 100,000 psi for A286 at 1095 °C. For closed-die forging blank sizing, oversize the forged bar by 5-10 % above the closed-die cavity volume. Aging shrinkage 0.05 % linear; design closed-die forging allowance accordingly. Forged bar should be ultrasonically inspected per ASTM A388 before downstream forging — internal flaws migrate and become surface defects in closed-die forging.
A286 Forged Bar Applications by Industry
A286 forged bar serves heavy-section high-temperature applications:
- Aerospace turbine shafting: Open-die forged ⌀ 75-150 mm round bar for jet-engine compressor and accessory drive shafts. Forging-grade microstructure provides superior fatigue performance vs hot-rolled.
- Industrial gas turbine main shafts: Forged ⌀ 150-300 mm round bar for Siemens / GE / Mitsubishi gas-turbine main shafts, generator coupling shafts. A286 gas turbine applications.
- Nuclear reactor internals: ASTM A638 grade 660 forged bar for ASME Section III control-rod-drive housings, pressuriser steam-discharge nozzles. A286 nuclear applications.
- Aerospace structural forging blanks: Forged bar as raw stock for downstream closed-die structural forgings — wing-spar root fittings, engine-mount lugs, landing-gear pivot blocks.
- Petrochemical pressure-vessel: Heavy forged bar for refinery hydrogen-service pressure-vessel internals, hydrogen-embrittlement-resistant downhole tool bodies.
- Power generation turbine blades: Forged bar as raw stock for steam-turbine and gas-turbine blade machining — forging produces aligned grain flow for fatigue performance.
Governing Standards & Material Specifications
Every A286 bar product is released against the applicable industry standard. EN 10204 type 3.1 mill certificates ship with every order. See the consolidated A286 AMS / ASTM specifications hub for full spec scope.
| Authority | Specification | Coverage |
|---|---|---|
| ASTM | A453 grade 660 Cl. A/B/C/D | High-temperature bolting material |
| ASTM | A638 grade 660 Type 1/2 | Forged bolting stock |
| ASTM | B637 | Precipitation-hardenable bar |
| AMS | 5731 | Bar / forging — solution-treated |
| AMS | 5732 | Bar / forging — solution-treated and aged |
| AMS | 5737 | Bar — sol-treated and aged (precision) |
| UNS | S66286 | Material designation |
| DIN | 1.4980 / X5NiCrTiMoVB25-15-2 | European designation |
| EN | 10204 3.1 / 3.2 | Mill / third-party-witness certification |
A286 Forged Bar vs Alternative Materials
Engineers compare A286 bar against three alternatives: A286 vs Inconel 718, A286 vs 17-4 PH, and A286 vs Waspaloy. See A286 equivalent grades.
How to Specify A286 Forged Bar
A complete a286 forged bar callout should include: material spec, heat-treatment condition, dimensional standard, size, surface finish, marking, inspection certificate. Example callout:
A286 forged bar, ASTM A638 grade 660 Type 1, AMS 5731 chemistry, sol-treated 1650 °F + aged 1325 °F × 16 h, ⌀ 150 mm × 3000 mm length, +5/-0 mm OD tolerance, ASTM A388 ultrasonic inspection Class 1, EN 10204 3.2 third-party witness.
A286 Forged Bar — Frequently Asked Questions
What is A286 forged bar used for?
Forged bar serves heavy-section high-temperature shafting, industrial gas-turbine main shafts, nuclear pressure-vessel internals, aerospace structural forging blanks. The forging-grade microstructure provides superior grain-flow continuity and isotropic mechanical properties vs hot-rolled bar of the same size.
What's the difference between forged bar and hot-rolled bar?
Forged bar: open-die or closed-die hot-forged from ingot — superior grain flow continuity, reduced macroscopic segregation, isotropic mechanical properties. Hot-rolled bar: rolled through a roll mill — directional grain flow, more economical for sizes ≤ 200 mm. Above 200 mm, forging is the dominant production route.
What's the maximum diameter of A286 forged bar?
Standard production: 300 mm (12 inch) round. Custom-drawing: up to 500 mm (20 inch) for special nuclear and pressure-vessel applications. Above 500 mm, custom forgings (not bar) are typically specified — see A286 forgings.
What is ASTM A638 grade 660 vs ASTM A453 grade 660?
ASTM A638: forgings spec — covers A286 in forged condition for high-temperature pressure-bearing service. Type 1 = higher RT tensile; Type 2 = higher stress-rupture. ASTM A453: bolting spec — covers A286 in wrought condition for high-temperature bolting. Both reference the same UNS S66286 chemistry.
Is A286 forged bar ultrasonically inspected?
Yes — 100 % UT per ASTM A388 / SE-388 with Class 1 acceptance for aerospace and nuclear lots. Internal-flaw detection critical for forging-grade applications. Smaller-diameter forged bar (75-150 mm): UT in straight-beam mode. Larger sizes: UT with angle-beam transducers.
Can A286 forged bar be supplied in cryogenic-tested condition?
Yes. Charpy V-notch testing per ASTM E23 at -196 °C available with EN 10204 3.2 third-party-witness for nuclear and cryogenic LNG / hydrogen applications. Typical Charpy V-notch ≥ 27 J at -196 °C for properly heat-treated forged A286.
What's the lead time on AMS 5732 forged bar?
75-150 mm: 8-12 weeks from heat release. 150-300 mm: 12-16 weeks (limited mill availability). Custom sizes > 300 mm: 16-24 weeks. Add 2-4 weeks for AS9102 first-article + EN 10204 3.2 third-party witness.
Is A286 forged bar magnetic?
No. Magnetic permeability < 1.005 verified per ASTM A342 — preserved through forging, cooling, sol-treatment, and aging. Compatible with downstream non-magnetic shaft and structural forging applications.
Can A286 forged bar replace Inconel 718 forged bar?
For service ≤ 700 °C — yes, A286 is approximately one-third the cost. For service > 700 °C, Inconel 718 retains strength up to 850 °C and remains preferred. See A286 vs Inconel 718 for the full comparison.
Why TorqBolt for A286 Forged Bar
Three reasons aerospace and gas-turbine OEMs place a286 forged bar orders with us:
- Vertically integrated supply — VIM-VAR melt sourcing from approved AMS-conforming mills, in-house hot-rolling + cold-drawing + vacuum heat-treatment. No outsourced critical step.
- Aerospace AQMS — AS9100D-certified factory in Mumbai with published quality manual.
- Lead time discipline — 4-6 weeks for ASTM A453 grade 660 standard sizes, 8-12 weeks for custom-drawing aerospace parts.
Three decades of fastener-manufacturing experience; current certifications: ISO 9001:2015, AS9100D, PED 2014/68/EU, NORSOK M-650 QTR.
Recent A286 Forged Bar Order Patterns
Active forged bar orders cover ⌀ 100 mm AMS 5732 open-die for aerospace turbine accessory shaft manufacture, ⌀ 200 mm ASTM A638 grade 660 Type 2 for industrial gas-turbine main shaft, custom 100 × 300 mm rectangular forged bar for nuclear pressure-vessel structural cladding, and ⌀ 250 mm AMS 5731 for high-temperature hydrogen-service downhole tool body machining.
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