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 Pipe
A286 pipe is high-temperature precipitation-hardening superalloy pipe used for fluid conveyance in jet-engine bleed-air, gas-turbine combustor manifolds, oil & gas downhole completion strings, and chemical-process high-temperature service lines. Distinguished from A286 tube/tubing by sizing convention (pipe = NPS / DN nominal pipe size with schedule wall thickness; tube = OD × wall) and primary use (pipe = pressure-bearing fluid conveyance per ASME B31; tube = mechanical / heat-exchange). TorqBolt manufactures A286 pipe to ASTM A312 (seamless / welded austenitic stainless pipe — extended for A286), ASTM A358 (electric-fusion-welded austenitic stainless pipe), ASME B36.10M (carbon steel pipe dimensions reference), and ASME B36.19M (stainless steel pipe dimensions). Sizes 1/8 inch through 24 inch NPS in schedules SCH 5S, 10S, 40S, 80S, 160. Heat-treated to deliver 130 ksi tensile / 95 ksi yield, retained mechanical properties to 700 °C continuous service. See parent A286 bar stock, sister A286 tubes/tubing, and the canonical chemical composition.
About A286 Pipe
A286 pipe is produced by either seamless extrusion (billet pierced + extruded over a mandrel + cold-finished) or welded (formed from A286 plate / sheet, longitudinally seam-welded, sometimes plug-rolled to remove weld bead). Seamless pipe (ASTM A312 SMLS) is preferred for high-pressure and aerospace service — uniform wall thickness, no weld defect risk. Welded pipe (ASTM A312 EFW or ASTM A358) is more economical for larger diameters and lower-pressure service. Pipe wall schedule conforms to ASME B36.19M tabulated dimensions. Each pipe lot is solution-treated 1650 °F and aged 1325 °F per AMS 5732, hydrostatic-pressure-tested per ASTM A312 / A358, ultrasonic-tested per ASTM A388, and ships with EN 10204 3.1 mill cert (3.2 third-party-witness available for nuclear and offshore service).
A286 Pipe Manufacturing Routes & Standards
TorqBolt produces A286 pipe via four primary routes:
- Seamless extruded pipe (ASTM A312 SMLS) — Billet pierced + extruded over a mandrel + cold-finished. Uniform wall thickness, no weld defect risk. Used for high-pressure aerospace and downhole-tool applications. Sizes 1/8-12 inch NPS.
- Welded pipe — longitudinal seam (ASTM A312 EFW / A358) — Formed from A286 plate or sheet, longitudinally seam-welded by TIG / plasma / electron-beam. Lower cost than seamless for larger diameters (8-24 inch NPS).
- Plug-rolled welded pipe — Welded pipe with weld bead plug-rolled to flush — restores uniform internal flow profile. Used for fluid-conveyance applications where weld bead would cause pressure-drop or sediment accumulation.
- Cold-drawn over mandrel pipe — Extruded pipe cold-drawn over a mandrel for tighter OD/ID tolerance and improved surface finish. Used for instrumentation and aerospace precision pipe.
- ASTM A312 high-temperature service — ASTM A312 covers seamless and welded austenitic stainless pipe extended to A286 chemistry — used for ASME B31.3 high-temperature process piping.
A286 Pipe Sizes & Schedule Reference (Selected NPS)
| NPS (inch) | OD (mm) | SCH 10S wall | SCH 40S wall | SCH 80S wall | SCH 160 wall |
|---|---|---|---|---|---|
| 1/2 | 21.34 | 2.11 mm | 2.77 mm | 3.73 mm | — |
| 3/4 | 26.67 | 2.11 mm | 2.87 mm | 3.91 mm | — |
| 1 | 33.40 | 2.77 mm | 3.38 mm | 4.55 mm | 6.35 mm |
| 1-1/2 | 48.26 | 2.77 mm | 3.68 mm | 5.08 mm | 7.14 mm |
| 2 | 60.32 | 2.77 mm | 3.91 mm | 5.54 mm | 8.74 mm |
| 3 | 88.90 | 3.05 mm | 5.49 mm | 7.62 mm | 11.13 mm |
| 4 | 114.30 | 3.05 mm | 6.02 mm | 8.56 mm | 13.49 mm |
| 6 | 168.28 | 3.40 mm | 7.11 mm | 10.97 mm | 18.26 mm |
| 8 | 219.08 | 3.76 mm | 8.18 mm | 12.70 mm | 23.01 mm |
| 12 | 323.85 | 4.57 mm | 10.31 mm | 17.48 mm | 33.32 mm |
A286 Pipe Manufacturing Process
Every a286 pipe TorqBolt ships traces back to a vacuum-induction-melted plus vacuum-arc-remelted (VIM-VAR) ingot meeting AMS 5731 / 5732 chemistry. Process route:
- VIM-VAR billet input: AMS 5731 / 5732 chemistry. Aerospace lots double-melted (VIM + VAR) for inclusion control.
- Billet piercing (seamless route): Billet hot-pierced through with a piercing punch at 1095 °C — creates initial hollow form. Critical: pierce concentric and uniform wall.
- Extrusion through die-and-mandrel: Hollow billet extruded at 1095-1150 °C through a die-and-mandrel set — simultaneous OD and ID formation.
- Cold drawing (precision lots): Extruded pipe cold-drawn over a mandrel for tighter OD/ID tolerance and improved surface finish per ASME B36.19M.
- Solution treatment: Vacuum or atmosphere furnace 1650 °F (AMS 5732). 1 h per inch of wall thickness, oil-quench.
- Precipitation aging: 1325 °F for 16 hours, air-cool. Hardness 29-32 HRC.
- Welding route (alternative for ≥ 8 inch NPS): Plate / sheet formed into pipe shape, longitudinal seam TIG / plasma / EB welded. Plug-rolling optional to flush weld bead.
- Hydrostatic pressure test: Each pipe length tested per ASTM A312 / A358 — 1.5× design pressure for 30 seconds, no leakage.
- Ultrasonic test (UT): 100 % UT per ASTM A388 — internal flaw detection. Aerospace and nuclear lots add Class 1 sensitivity acceptance.
A286 Pipe 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:
- OD and wall thickness verified by laser micrometer per ASME B36.19M tolerance.
- Ovality check per ASTM A312 — typically max 1 % of nominal OD.
- Hydrostatic pressure test 100 % per ASTM A312 / A358 — 1.5× design pressure.
- Ultrasonic test 100 % per ASTM A388 — internal flaw detection. Class 1 for aerospace / nuclear.
- Surface inspection 100 % visual + dye-penetrant LPI per ASTM E1417 on aerospace.
- Hardness sample 1 per heat per ASTM E384.
- Tensile coupon from each heat per ASTM E8 + elevated-temperature per E21.
- 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 Pipe Installation & Service Practice
A286 pipe is fluid-conveyance — pressure rating per ASME B31 calculation using wall thickness, OD, and A286 yield stress at temperature. For an 8 inch NPS SCH 80S A286 pipe (12.7 mm wall), max design pressure at 700 °C is approximately 50-60 bar (depending on B31 design code used). Thermal expansion coefficient 17.0 µm/m·°C — long pipe runs require expansion loops or bellows. For high-pressure aerospace bleed-air pipes, design wall thickness for 4× safety factor over working pressure to account for fatigue cycling and thermal-mechanical fatigue from start-stop cycles.
A286 Pipe Applications by Industry
A286 pipe serves high-temperature pressure-bearing fluid-conveyance applications:
- Jet-engine bleed-air piping: Aerospace seamless A286 pipe for jet-engine bleed-air ducts, anti-ice supply lines, environmental-control system pressurisation. Service to 700 °C with 35 bar pressure. A286 jet engine fasteners ecosystem.
- Industrial gas turbine combustor manifold: A286 pipe as combustor fuel-distribution manifolds, ignition pilot lines. Resists fuel-side corrosion + 700 °C exhaust-side. A286 gas turbine applications.
- Oil & gas downhole completion: A286 seamless pipe for sour-service completion strings, perforating-gun retrieval pipe. NACE MR0175 sour-service compliant when hardness ≤ HRC 35.
- Petrochemical hydrogen-service piping: A286 pipe for refinery hydrogen-service process lines — resistant to high-temperature hydrogen attack (HTHA) at 540-700 °C operating temperatures.
- Cryogenic LNG transfer piping: A286 pipe for LNG storage-vessel internal transfer lines + hydrogen-storage manifold piping. Retains 85 % of room-temperature toughness at -196 °C.
- Nuclear pressure-vessel internal piping: ASTM A453 grade 660 / ASME III A286 pipe for nuclear reactor internal instrumentation tubing, control-rod-drive housing penetrations. A286 nuclear applications.
Governing Standards & Material Specifications
Every A286 product is released against the applicable industry standard. EN 10204 type 3.1 mill certificates ship with every order. See A286 AMS / ASTM specifications hub.
| Authority | Specification | Coverage |
|---|---|---|
| ASTM | A453 grade 660 Cl. A/B/C/D | High-temperature bolting material |
| ASTM | A638 grade 660 Type 1/2 | Forged stock |
| AMS | 5731 | Bar / forging — solution-treated |
| AMS | 5732 | Bar / forging — solution-treated and aged |
| UNS | S66286 | Material designation |
| DIN | 1.4980 / X5NiCrTiMoVB25-15-2 | European designation |
| EN | 10204 3.1 / 3.2 | Mill / third-party-witness certification |
| NACE | MR0175 / ISO 15156-3 | Sour-service hardness limit ≤ HRC 35 |
A286 Pipe vs Alternative Materials
Engineers compare A286 against three alternatives: A286 vs Inconel 718, A286 vs 17-4 PH, and A286 vs Waspaloy. See A286 equivalent grades.
How to Specify A286 Pipe
A complete a286 pipe callout should include all relevant elements. Example callout:
A286 pipe, ASTM A312 grade A286 (UNS S66286), ASTM A453 grade 660 chemistry, sol-treated and aged, NPS 4 inch × SCH 80S (114.3 mm OD × 8.56 mm wall) × random 6 m length, hydrostatic pressure tested, EN 10204 3.1, ultrasonic tested per ASTM A388.
A286 Pipe — Frequently Asked Questions
What's the difference between A286 pipe and A286 tube?
Pipe: NPS / DN nominal pipe size + schedule wall thickness, primary use as pressure-bearing fluid conveyance per ASME B31. Tube: OD × wall thickness, primary use as mechanical / heat-exchanger / instrumentation. Same A286 material, different sizing convention and intended application.
What ASTM standard covers A286 pipe?
ASTM A312 (seamless and welded austenitic stainless pipe) and ASTM A358 (electric-fusion-welded austenitic stainless pipe) extended for A286 chemistry. Reference ASTM A453 grade 660 for the underlying material spec. ASME B36.19M defines stainless pipe dimensions.
Can A286 pipe be welded in field?
Yes — TIG / GTAW with matching A286 welding rod (AMS 5853) for field installation joints. Pre-heat NOT required for thicknesses ≤ 50 mm. Post-weld heat treatment required for full-strength weld zone — solution-treat 1650 °F + age 1325 °F.
What's the maximum diameter of A286 pipe?
Standard production: 24 inch NPS welded (610 mm OD), 12 inch NPS seamless (323 mm OD). Larger diameters available custom — typically welded with longitudinal seam + plug-rolling for bigger sizes.
Is A286 pipe NACE MR0175 compliant?
Yes — when supplied with hardness ≤ HRC 35 (HV ≤ 327) per NACE MR0175 / ISO 15156-3 for sour-service downhole and oilfield applications. Specify on PO; each heat receives Vickers traverse.
Is A286 pipe magnetic?
No. Magnetic permeability < 1.005 verified per ASTM A342. Critical for instrumentation tubing and sensitive aerospace bleed-air applications where adjacent magnetic material would cause EMI.
What's the temperature limit of A286 pipe?
Continuous service: 700 °C (1300 °F). Oxidation-resistant to 982 °C (1800 °F). Stress-rupture life decreases above 700 °C — for sustained service > 700 °C use Inconel 718 or Waspaloy. See A286 vs Inconel 718.
Can A286 pipe be supplied schedule 160 (heavy wall)?
Yes for sizes 1 inch NPS and larger. Schedule 160 wall thickness ranges from 6.35 mm at 1 inch NPS to 33.32 mm at 12 inch NPS. Used for high-pressure downhole and aerospace bleed-air applications.
What's the lead time on AMS 5732 A286 pipe?
Standard sizes 1-4 inch NPS: 8-12 weeks from heat release. Larger sizes 6-12 inch NPS: 12-16 weeks. Custom 14-24 inch NPS welded: 14-20 weeks. Aerospace AS9102 first-article: add 2-3 weeks.
Why TorqBolt for A286 Pipe
Three reasons aerospace and industrial OEMs place a286 pipe orders with us:
- Vertically integrated supply — VIM-VAR melt sourcing, in-house forging + machining + vacuum heat-treatment.
- 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 manufacturing experience; current certifications: ISO 9001:2015, AS9100D, PED 2014/68/EU, NORSOK M-650 QTR.
Recent A286 Pipe Order Patterns
Active A286 pipe orders cover 1-2 inch NPS SCH 80S seamless for jet-engine bleed-air ducts, 4-6 inch NPS SCH 40S welded for industrial gas-turbine combustor manifold piping, custom 8-12 inch NPS SCH 80S for nuclear pressure-vessel internal piping, and 1/2-3/4 inch SCH 160 for oilfield downhole completion strings.
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