Inconel 718 Pipe & TubeManufacturer, trader & exporter, India
Also sold as Alloy 718 · UNS N07718 · W.Nr 2.4668 · Precipitation-hardening nickel alloy
Inconel 718 pipe and tube are not an established product form in our catalogue, and no pipe or tube specification is asserted for Inconel 718 here. Send your specification and quantity and we will confirm what can be supplied. It is a age-hardenable nickel–chromium alloy with niobium and molybdenum, chosen for very high strength at temperatures up to about 650 °C. Kanak Steel & Engineering Co. manufactures, trades and exports it from Mumbai; EN 10204 3.1 or 3.2 certificates are available on request / as specified in the PO. Markets we have supplied to include Oman, UAE, Saudi Arabia, Brazil, Argentina, Spain and Chile (India is the home market).
- Stock & mill supply
- EN 10204 3.1 / 3.2
- PMI on request
- NACE MR0175 on request
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is Inconel 718 Pipe & Tube?
Inconel 718 pipe & tube is an age-hardenable nickel–chromium alloy with niobium and molybdenum supplied as pipe & tube to a specification not yet established (UNS N07718). Buyers specify it for very high strength at temperatures up to about 650 °C. It is also sold as Alloy 718, UNS N07718, W.Nr 2.4668.
- What it is
- Age-hardenable nickel–chromium alloy with niobium and molybdenum
- Seamless
- a specification not yet established
- Welded
- a specification not yet established
- Sizes
- NPS ⅛" – 24" · OD tube to order
- Schedules
- 5S · 10S · 40S · 80S · 160 · XXS
- Best at
- Very high strength at temperatures up to about 650 °C
Inconel 718 Pipe & Tube Specification & Sizes
| Seamless pipe | a specification not yet established |
|---|---|
| Welded pipe | a specification not yet established |
| Tube | a specification not yet established |
| Grade | Inconel 718 · UNS N07718 · W.Nr 2.4668 |
| Size & schedule | NPS ⅛" to 24" to ASME B36.19 / B36.10; OD × wall for tube |
| Length | Single random, double random, or cut lengths |
| Ends | Plain end · bevelled end (for welding) · threaded |
| Testing | Hydrostatic or eddy-current · PMI · flattening & flaring · IGC on request |
| Documents | EN 10204 3.1 · 3.2 with third-party inspection |
Inconel 718 Pipe: Seamless, Welded or Tube?
Three different specifications cover 718 tubular products. Pick the route first — it decides price, test requirements and lead time. General requirements (tolerances, hydrostatic or electric testing) come from ASTM B829 (seamless) and B775 (welded). Schedules, the −12.5% wall tolerance and the B31.3 wall formula are explained in the pipe guide.
| Route | Specification | Use it for |
|---|---|---|
| Seamless pipe | a specification not yet established | Pressure and critical service; no weld seam to inspect. |
| Welded pipe | a specification not yet established | Economical in larger diameters and thinner walls where the code allows it. |
| Tube | a specification not yet established | Heat exchangers and instruments; ordered by exact OD × wall. |
Inconel 718 Pipe Wall & Weight by Schedule
For the same size, the schedule sets the wall — and the weight you pay for. Cross-sections are drawn to scale for 2" NPS (OD 60.33 mm, ASME B36.19); weights use the density of Inconel 718, 8.19 g/cm³.
Other sizes: pipe schedule chart and weight calculator.
Inconel 718 Pipe & Tube Chemical Composition
| Element | Weight % (producer reference) |
|---|---|
| Nickel (+Co) | 50.00 – 55.00 |
| Chromium | 17.00 – 21.00 |
| Iron | Balance |
| Niobium (+Ta) | 4.75 – 5.50 |
| Molybdenum | 2.80 – 3.30 |
| Titanium | 0.65 – 1.15 |
| Aluminium | 0.20 – 0.80 |
| Cobalt | 1.00 max |
| Carbon | 0.08 max |
| Manganese | 0.35 max |
| Silicon | 0.35 max |
| Phosphorus | 0.015 max |
| Sulphur | 0.015 max |
| Boron | 0.006 max |
| Copper | 0.30 max |
Inconel 718 Pipe & Tube Mechanical Properties
No specification requirement is asserted for this product form; requirements are to the purchase specification.
Density & Physical Properties
| Property | Value |
|---|---|
| Density | 8.19 g/cm³ |
| Melting range | 1260 – 1336 °C |
| Magnetic | Non-magnetic |
Typical / reference values (producer data, Special Metals SMC-045) — not specification requirements.
Inconel 718 Equivalent Grades
Values follow Special Metals INCONEL alloy 718 bulletin SMC-045 (2007) — producer reference composition, not a specification requirement; specification limits in ASTM B637-26, B670-25 and A1014/A1014M-26 are pending current standard text. Always check against the edition named on your purchase order.
Inconel 718 Pipe Weight Chart (kg/m)
Weight per metre (kg/m) = (OD − WT) × WT × 0.02573, with OD and wall thickness in mm. The factor comes from Inconel 718's density of 8.19 g/cm³.
Example: 4" Sch 40S (114.30 × 6.02 mm)
(114.30 − 6.02) × 6.02 × 0.02573 = 16.77 kg/m
| NPS | OD mm | Sch 10S kg/m | Sch 40S kg/m |
|---|---|---|---|
| ½" | 21.34 | 1.04 | 1.32 |
| 1" | 33.40 | 2.18 | 2.61 |
| 2" | 60.33 | 4.10 | 5.68 |
| 3" | 88.90 | 6.74 | 11.78 |
| 4" | 114.30 | 8.73 | 16.77 |
| 6" | 168.28 | 14.42 | 29.48 |
| 8" | 219.08 | 20.83 | 44.39 |
Six-digit Harmonized System heading (nickel alloy, chapter 75). Your country adds its own digits — confirm with your customs broker. All HS codes.
How to Verify Inconel 718 Pipe & Tube with PMI
Positive material identification with a handheld XRF gun confirms the alloy on the piece itself, in seconds, before it is cut or welded. Inconel 718 is most often mixed up with Inconel 625 — the table shows which elements tell them apart.
Handheld XRF does not measure carbon or nitrogen; those come from the mill certificate or optical emission (OES) testing. PMI can be arranged on request — state it on your enquiry.
Under technical review for TDS.
| Element | Inconel 718 (producer reference) | Inconel 625 |
|---|---|---|
| Nickel | 50.00 – 55.00 | As specified |
| Chromium | 17.00 – 21.00 | As specified |
| Molybdenum | 2.80 – 3.30 | As specified |
| Copper | 0.30 max | — |
| Titanium | 0.65 – 1.15 | As specified |
| Niobium | 4.75 – 5.50 | As specified |
| Iron | Balance | As specified |
| Manganese | 0.35 max | As specified |
Inconel 718 Pipe & Tube Price — What Decides It
Two quotes for "718 pipe & tube" can differ by 20% and both be fair. We quote 718 pipe & tube per kg for full sizes and per piece for cut sizes. These six things move the price per kg, so you can compare offers like for like.
Inconel 718 Pipe & Tube Applications
Inconel 718 is specified when the cheaper grade will not survive the service but a higher alloy would be more than the job needs. These are the jobs our buyers use it for.
Inconel 718 Pipe & Tube vs 625, 600 and 825
| Grade | Pipe & Tube standard | PREN (approx.) | Pick it when |
|---|---|---|---|
| Inconel 600 | ASTM B167 | — | High-temperature oxidation, caustic and nuclear service |
| Inconel 718 | a specification not yet established | — | Very high strength at temperatures up to about 650 °C |
| Inconel 825 | ASTM B423 | ≈ 31 | Sulphuric and phosphoric acid service, chloride stress-corrosion cracking and sour gas |
| Inconel 625 | ASTM B444 | ≈ 51 | Seawater, high strength and high temperature in one alloy |
PREN = Cr + 3.3 Mo + 16 N, from mid-range chemistry. A screening guide, not a substitute for corrosion data on your medium.
Inconel 718 Corrosion Resistance — Element by Element
Each alloying addition has a job. Knowing which one protects against your medium is the quickest way to judge whether 718 fits.
Niobium forms the gamma-double-prime precipitate that gives 718 its high strength after age hardening.
Keeps very high strength and creep resistance up to about 650 °C.
Its slow ageing response gives good resistance to strain-age cracking during post-weld heat treatment; welding procedure and post-weld treatment still follow the applicable code and specification.
718 is chosen for strength; for corrosion alone, 625 or 825 are usually better value.
How your 718 pipe & tube order runs
- 01Enquiry review — we confirm size, standard edition and documents against your MR or drawing.
- 02Heat selection & PMI — the mill certificate is checked against your order; PMI can be arranged depending on product and requirements, as specified in the PO.
- 03Processing — cutting, machining or bevelling to your specification, with heat numbers marked as specified in the PO.
- 04Inspection — your third-party inspector witnesses, or we share photos and test reports.
- 05Packing & dispatch — seaworthy packing from Nhava Sheva (JNPT), Mumbai, FOB or CIF, documents sent before the vessel sails.
Welding & Fabricating Inconel 718 Pipe & Tube
Inconel 718 welds by all common arc processes. A few points our buyers ask about:
| Matching filler | ERNiFeCr-2 (AWS A5.14) |
|---|---|
| Over-alloyed filler | Post-weld solution treatment and ageing restore strength |
| Preheat | Not required; keep interpass temperature low |
| Cutting | Thermal or abrasive cutting; grind off heat-tinted edges before welding |
Follow your approved WPS; this is general guidance. See also 718 fittings and 718 flanges for the matching pipe-system parts.
How to Order Inconel 718 Pipe & Tube: RFQ Checklist
Get an accurate quote the first time. Copy this list into your enquiry:
- Seamless or welded, and the standard
- NPS and schedule (or OD × wall for tube)
- Length — random or cut, and number of lengths
- End finish — plain, bevelled or threaded
- Certificate type and extra tests
- Delivery port, Incoterm and required date
Inconel 718 pipe & tube — questions buyers ask
Is Inconel 718 the same as Alloy 718?
Alloy 718, UNS N07718, W.Nr 2.4668 are names used for Inconel 718 (W.Nr / EN numbers and older UNS variants are the closest designations; their limits can differ slightly, so specify the UNS number and ASTM grade on the order), and pipe & tube is ordered to a specification not yet established whichever name is on the enquiry.
What is the difference between Inconel 718 pipe and tube?
Pipe is ordered by nominal pipe size and schedule, for carrying fluids. Tube is ordered by exact outside diameter and wall, for heat exchangers and instruments, and is held to tighter tolerances.
Seamless or welded Inconel 718 pipe — which should I buy?
No Inconel 718 pipe specification is asserted in our catalogue; seamless versus welded is decided by your design code and purchase specification.
What is the wall-thickness tolerance on Inconel 718 pipe?
Seamless pipe is normally allowed −12.5% on nominal wall under its general-requirements standard (ASTM B829 (seamless) and B775 (welded)). Allow for it in the pressure calculation or order on minimum wall.
Can Inconel 718 pipe be welded to carbon-steel pipe?
Yes, with the right filler: a nickel-base filler such as ERNiCr-3 (or ERNiCrMo-3) is used when joining it to carbon steel. Follow a qualified WPS.
Can Inconel 718 pipe & tube be supplied to NACE MR0175?
Inconel 718 (UNS N07718) can be supplied for sour service when the PO specifies NACE MR0175 / ISO 15156; acceptability depends on the material condition, hardness and the environmental limits in that standard, which the purchaser must confirm for the application.
Inconel 718 or Inconel 825 — which should I choose?
Inconel 718 is chosen for very high strength at temperatures up to about 650 °C. Inconel 825 is the step up when you need more pitting resistance or strength. See the comparison table on this page, or ask us with your process conditions.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026