Gas Turbine Fuel and Cooling Air Lines
High-pressure fuel lines and cooling air lines on gas turbines are run in Alloy 718 seamless pipe, which delivers the 862 MPa yield minimum that ASTM B983 sets for the precipitation-hardened condition.
ASTM B983 / UNS N07718 / W.Nr. 2.4668
Inconel 718 Seamless Pipes Manufacturer in Thailand
For high-pressure fuel and cooling air lines, liquefied gas plumbing and downhole pressure-containing parts, Thaida Stainless Steel Manufacturing (Thailand) Co., Ltd. manufactures Inconel 718 seamless pipes to ASTM B983 at its mill in Ban Bueng, Chonburi, Thailand. The alloy is UNS N07718, written W.Nr. 2.4668 on European drawings, and it is the precipitation-hardened grade within our Inconel seamless pipes group. Our Bang Phli, Samut Prakan office prepares inquiries, quotations and export paperwork.
Inconel 718 seamless pipeUNS N07718 / W.Nr. 2.4668
- 6 to 457 mmOutside diameter
- 1 to 65 mmWall thickness
- Up to 18 mLength
- EN 10204 3.1Test certificate
EN 10204 3.1 certificate / 3.2 on request
Specifications of ASTM B983 Inconel 718 Seamless Pipes
Each line is ordered by standard pipe size and schedule. The rows set out the diameter, wall and length we produce for an Inconel 718 seamless pipe order, the delivery condition required for UNS N07718, and the checks made before release.
- Standard
- ASTM B983
- Grade
- 718 (UNS N07718)
- Outside Diameter
- 6 to 457 mm
- Wall Thickness
- 1 to 65 mm
- Length
- Up to 18 m
- Ordering Basis
- Standard pipe size and schedule
- End Type
- Plain endscut and deburred
- Delivery Condition
- Solution annealed plus precipitation hardened, descaled
- Form
- Seamless
- Testing
- Chemical analysis and tension test per lot
- Hydrostatic or nondestructive electric test on each pipe
- Test Certificate
- EN 10204 3.13.2 on request
ASTM B983, Standard Specification for Precipitation Hardened or Cold Worked, Seamless Nickel Alloy Pipe and Tube, is the product standard behind every ASTM B983 Inconel 718 seamless pipe we make. Its scope lists eight nickel alloys, UNS N07718 among them, and it identifies each one by UNS number alone: Inconel 718 and Alloy 718 are commercial names carried on requisitions, while the standard itself speaks of N07718. The companion Inconel 718 seamless tubes follow the same standard but are ordered on outside diameter plus a minimum or average wall and a cut length.
Each lot is covered by a single chemical analysis and a single tension test, and every length is then either pressure tested with water or examined by a nondestructive electric method. The figures are reported on an EN 10204 3.1 (3.2 on request) material test certificate covering the heat analysis and the lot tension result. An independent inspector can witness testing and release when the order asks for one.
UNS N07718 Seamless Pipe Chemical Composition
Iron, not nickel, is the remainder element in UNS N07718 seamless pipe. Nickel is held between 50.0 and 55.0% and chromium between 17.0 and 21.0%, with niobium, molybdenum, titanium and aluminum each set within a closed range. ASTM B983 prints the niobium row under its older name, columbium, and the 4.75 to 5.50% limit applies to that element alone, since the separate columbium-plus-tantalum row carries no requirement for this alloy.
- FeIron, Remainder
- NiNickel, 50.0 to 55.0
- CrChromium, 17.0 to 21.0
- NbNiobium, 4.75 to 5.50
- MoMolybdenum, 2.80 to 3.30
UNS N07718718
| Element | Limit per ASTM B983 (%) |
|---|---|
| Ni (Nickel) | 50.0 to 55.0 |
| Cr (Chromium) | 17.0 to 21.0 |
| Fe (Iron) | Remainder |
| Nb (Niobium) | 4.75 to 5.50 |
| Mo (Molybdenum) | 2.80 to 3.30 |
| Ti (Titanium) | 0.65 to 1.15 |
| Al (Aluminum) | 0.20 to 0.80 |
| Co (Cobalt) | 1.0 max |
| C (Carbon) | 0.08 max |
| Mn (Manganese) | 0.35 max |
| Si (Silicon) | 0.35 max |
| P (Phosphorus) | 0.015 max |
| S (Sulfur) | 0.015 max |
| B (Boron) | 0.006 max |
| Cu (Copper) | 0.30 max |
Phosphorus and sulfur are each capped at 0.015% and boron at 0.006%. Iron may be determined arithmetically by difference, which is why it appears as the remainder rather than as a range.
Mechanical Properties of Seamless Nickel Alloy 718 Pipe
ASTM B983 tabulates one room-temperature row for UNS N07718, tied to the solution annealed plus precipitation hardened condition, and a seamless nickel alloy 718 pipe must meet it as delivered.
| Property | Value | Unit |
|---|---|---|
| Condition | Solution annealed plus precipitation hardened | |
| Tensile Strength, min | 1034 (150) | MPa (ksi) |
| Yield Strength, min | 862 (125) | MPa (ksi) |
| Elongation in 2 in. (50 mm) or 4D, min | 20 | % |
| Hardness, max | 40 | Rockwell C |
The tension test run on each lot checks tensile strength, yield strength and elongation together against this row.
Equivalent Designations of Inconel 718
Inconel 718 is written in these ways on American, European, Japanese and Chinese drawings. ASTM B983 assigns only the UNS number; the remaining entries are cross-references for matching a drawing callout and carry no claim of conformity to another national standard.
- ASTM B983 (USA)UNS N07718
- Commercial name (USA)Inconel 718, also written Alloy 718
- Europe (W.Nr.)2.4668
- Japan (JIS)NCF718
- China (GB)GH4169
A requisition written for 2.4668, NCF718 or GH4169 is matched to N07718 when the order is entered, and the material is certified against ASTM B983 under that number.
Delivery Condition and Fabrication of Seamless Inconel 718 Pipe
ASTM B983 recognizes three supply conditions: cold worked; cold worked and precipitation hardened; and solution annealed plus precipitation hardened. Only the last has a property row for UNS N07718, so that is how this pipe ships. Pipe is descaled after heat treatment unless the furnace runs under atmosphere control, in which case the standard waives descaling. The solution and aging cycles appear in B983 as recommendations only; what the standard enforces is the delivered condition and the property row above, and the mill sets its cycle to meet them.
Ends arrive plain, cut and deburred, ready for the bevel your welding procedure calls for. A non-mandatory appendix of B983 states that proper heat treatment during or after fabrication is needed for optimum performance and that the manufacturer should be consulted on the details. Send the welding procedure and any planned post-weld heat treatment with the inquiry, and we review them against the condition the pipe is delivered in.
Seamless WNR 2.4668 Pipe Sizes and Hot-Worked Tolerances
Our seamless WNR 2.4668 pipe range runs 6 mm to 457 mm across the outside diameter, 1 mm to 65 mm through the wall, and to 18 m in length. Within that range each line is called up as a pipe size and schedule, and our offer states the matching diameter and wall.
ASTM B983 runs two dimensional regimes. Clause 14.1 applies its own hot-finished tables to pipe finished hot, and those tables run past 9 1/4 in. (235 mm) outside diameter. Clause 14.2 holds precipitation-hardened and cold-worked pipe to the standard's cold-worked limits for dimensions, straightness and ovality, which are closer, and the quotation names the set that governs each size. These are the B983 hot-worked pipe rows for the larger bores:
| Nominal OD, in. (mm) | OD Tolerance, in. (mm) | Nominal Wall Tolerance | Minimum Wall Tolerance |
|---|---|---|---|
| Over 4 1/2 (114) to 6 1/2 (165), incl. | ±0.047 (±1.2) | +16.0% / -12.5% | +28.5% / 0 |
| Over 6 1/2 (165) to 9 1/4 (235), incl. | ±0.062 (±1.6) | +16.0% / -12.5% | +28.5% / 0 |
| Over 9 1/4 (235) to 14 (356), incl. | ±0.120 (±3.05) | +16.0% / -12.5% | Not tabulated |
| Over 14 (356) to 24 (610), incl. | ±0.20 (±5.08) | +16.0% / -12.5% | Not tabulated |
Swipe sideways to see the full table.
Up to 5 in. (127 mm) outside diameter, each individual reading has to fall inside the band, ovality included. Above 5 in., the band applies to the mean diameter and no single reading may exceed twice the tabulated value. Eccentricity is counted within the individual measurements throughout. Because the final band is printed to 24 in. (610 mm) while our production stops at 457 mm, the largest pipe we can make, rather than the table, caps a large-bore size list.
Seamless Alloy 2.4668 Pipe Beside Inconel 625 and 600
Inconel 625 seamless pipes are made to ASTM B444 in two annealed grades with no aging step, while 718 gains its strength from precipitation hardening under B983. Our 625 pipe range stops at 35 mm wall, and seamless alloy 2.4668 pipe is produced up to 65 mm, which settles the choice on very heavy-walled spools.
Inconel 600 seamless pipes follow ASTM B167 and contain at least 72.0% nickel, against 50.0 to 55.0% in 718. In its B167 conditions 600 is held to a yield minimum between 170 and 240 MPa, depending on condition and diameter, compared with 862 MPa for precipitation-hardened 718.
Industrial Applications of Alloy 718 Seamless Pipe
Seamless Inconel 718 pipe is chosen for pressure-containing lines in gas turbines, propulsion systems, liquefied gas storage and oil and gas wells.
Liquefied Gas Storage Plumbing
Plumbing lines for liquefied gases, including the piping of liquid oxygen and hydrogen storage systems, use this pipe where the line calls for a seamless, high-strength nickel alloy with certified heat chemistry.
Liquid-Fueled Rocket Motor Lines
Propellant and oxidizer flow lines in liquid-fueled rocket motors are built from seamless nickel alloy 718 pipe, with chemistry and tension results reported per lot so every line traces back to its heat.
Downhole Tool Housings and Completion Equipment
Downhole tooling housings, pressure-containing components, high-strength tubing, casing connectors and completion tools for high-pressure oil and gas wells draw on seamless alloy 2.4668 pipe for strength in the pipe wall.
How Seamless 2.4668 Pipe Is Packed and Shipped
Packing
Larger bores in strapped bundles on timber bearers, smaller sizes in wooden cases, every length capped at both ends.
Marking
UNS N07718, ASTM B983, heat number and nominal size on each seamless 2.4668 pipe, with a bundle tag for small or short pieces.
Documents
EN 10204 3.1 (3.2 on request) material test certificate, filed under the heat numbers marked on the pipe.
Incoterms quoted
FOB, CIF or CFR, naming the destination port in the offer.
Dispatch
Booked against the production slot confirmed on the order acknowledgement.
Seamless 718 Pipe Price per kg
As an indicative guide, Inconel 718 seamless pipe sells for USD 24 to 55 per kg. Three factors place an order within that band: the nickel market, followed to a smaller degree by niobium and molybdenum; the heat treatment behind the precipitation-hardened delivery condition; and the size, quantity, documentation and any extra testing or traceability on the order. Send the line list with quantities and we turn the indication into a dated quotation.
Indicative price, Inconel 718 Seamless Pipes
USD 24 to 55 per kg
Indicative only. Send your sizes and specification to Thaida for a firm quotation.
- Outside diameter
- Quantity
- Testing and certification
- Nickel price
- Molybdenum price
Mill, Office and Export Markets
Our mill is at 154 Moo.1 Map Phai, Ban Bueng, Chonburi 20170, Thailand, and the sales and documentation office is at 89/18 Moo.15 Enterprize Park, Bangna-Trad Road, Bang Kaeo, Bang Phli, Samut Prakan 10540, Thailand. Inconel 718 seamless pipe leaves the mill for projects across Thailand and for export to Singapore, Malaysia, Vietnam, Indonesia, the Philippines and India.
Factory154 Moo.1 Map Phai, Ban Bueng,
Chonburi 20170, Thailand
Chonburi 20170, Thailand
Office89/18 Moo.15 Enterprize Park, Bangna-Trad Road,
Bang Kaeo, Bang Phli, Samut Prakan 10540, Thailand
Bang Kaeo, Bang Phli, Samut Prakan 10540, Thailand
Exporting to
- Singapore
- Malaysia
- Vietnam
- Indonesia
- Philippines
- India
Seamless Precipitation-Hardened 718 Pipe FAQ
Which specification goes on an order for 718 seamless pipe, and is there an ASME number?
Cite ASTM B983 and UNS N07718. B983 has no ASME SB specification counterpart, so the order cites the ASTM standard and the UNS number. That differs from the 600, 601 and 625 grades in the family, whose product standards each have an ASME equivalent.
What condition is UNS N07718 seamless pipe delivered in?
Solution annealed plus precipitation hardened, the one condition ASTM B983 tabulates for this alloy. Tension specimens are cut after that final heat treatment and pulled in the direction of fabrication, in full pipe section whenever possible, so the certified tensile result describes the pipe exactly as it arrives on site.
How does seamless Inconel 718 pipe compare with Inconel 625 on strength?
718 carries the higher strength minimums and the lower elongation minimum. ASTM B983 requires 1034 MPa tensile, 862 MPa yield and 20% elongation; ASTM B444 sets 625 Grade 1 at 827 MPa, 414 MPa and 30%, and Grade 2 at 690 MPa, 276 MPa and 30%. Send your design basis and we confirm which grade fits the line.
Which diameter tolerances apply to seamless 718 pipe above 9 1/4 in. (235 mm)?
In the hot-worked regime, ASTM B983 allows ±0.120 in. (3.05 mm) on diameter up to 14 in. (356 mm) and ±0.20 in. (5.08 mm) from there to 24 in. (610 mm), with nominal wall at +16.0% / -12.5%. Neither band carries a minimum-wall figure, so state nominal wall for these sizes or agree the basis at quotation.
Can a hydrostatic test above 1000 psi be ordered for Alloy 718 seamless pipe?
Yes. ASTM B983 allows a test pressure above 1000 psi by agreement between you and the manufacturer, or at the manufacturer's option, provided the allowable fiber stress invoked by B983 is not exceeded. The agreed pressure is fixed per size at order entry and recorded against every length.
How is seamless WNR 2.4668 pipe retested if a tension test fails?
The lot gets a second chance on two fresh specimens, each cut from a different sample piece, and both have to meet the ASTM B983 requirements. Chemical analysis and the tension test are each run once per lot, so the retest decides the whole lot rather than one length.
What size range can be ordered in seamless alloy 2.4668 pipe?
Diameter 6 to 457 mm, wall 1 to 65 mm, and length to a maximum of 18 m. Imperial pipe sizes and metric callouts are both accepted, and a size list that mixes the two is priced line by line in a single offer.
Which documents travel with each 718 seamless pipe consignment?
Each consignment carries an EN 10204 3.1 (3.2 on request) certificate together with the packing list and commercial invoice. ASTM B983 makes certification due only when the order specifies it, and we issue the certificate on every order regardless. It identifies the material as UNS N07718 and ties every result to the heat number in the pipe marking.
Request a Quote for Inconel 718 Seamless Pipes
or email sales@thaida.co.th