Inconel 718 Forged Seamless Pipe
Table Of Content
What is Inconel 718 pipe?
Inconel 718 (UNS N07718 / W.Nr. 2.4668) is a precipitation-hardenable nickel alloy. For forged seamless pipe, specify the required manufacturing route, material condition, outside diameter, wall thickness and inspection criteria together. Grade designation alone does not define the finished pipe performance.
Request a quote for your pipe dimensions
Specifications of Inconel 718 Forged Seamless Pipe
| Item | Specification / order requirement |
|---|---|
| Material | Inconel 718, UNS N07718, W.Nr. 2.4668 |
| Product form | Round forged seamless pipe or machined hollow. Confirm the manufacturing route and final product specification with the quotation. |
| Seamless pipe / tube standard | ASTM B983 includes UNS N07718 high-strength seamless pipe and tube. Confirm the specified edition and delivery condition. |
| Aerospace tubing specifications | SAE AMS 5589 and AMS 5590 apply to seamless tubing with different solution heat-treatment requirements. They are not interchangeable ASTM specifications. |
| Dimensions | Specify outside diameter (OD), inside diameter (ID) or wall thickness (WT), length, dimensional tolerances and any machining allowance. |
| Material condition | State the required solution treatment and, where applicable, precipitation hardening condition. Confirm it against the ordered specification. |
| Ends and surface | Specify plain or beveled ends, drawing details, surface finish and cleanliness. Availability is subject to technical confirmation. |
| Inspection and documentation | Define required chemistry, mechanical tests, NDT, dimensional inspection, heat traceability and certificate type before ordering. |
| Quotation details | Send quantity, dimensions, drawing if available, standard, material condition, application and delivery destination. |
Specification reference: ASTM B983 scope.
Inconel 718 Pipe and Tube Examples
Chemical Composition of Inconel 718
| Element | Composition, mass % |
|---|---|
| Nickel + cobalt | 50.00–55.00 |
| Chromium | 17.00–21.00 |
| Iron | Balance |
| Niobium + tantalum | 4.75–5.50 |
| Molybdenum | 2.80–3.30 |
| Titanium | 0.65–1.15 |
| Aluminum | 0.20–0.80 |
| Carbon | 0.08 maximum |
Selected composition limits from the Special Metals alloy 718 technical bulletin. The ordered specification and heat-specific material certificate govern acceptance, including elements not shown here.
Mechanical Properties and Delivery Condition
| Property | What to confirm |
|---|---|
| Tensile and yield strength | Required minimum values, test temperature, specimen orientation and material condition under the ordered specification. |
| Elongation | Required minimum and gauge length for the applicable specimen and product dimensions. |
| Hardness | Test method, scale, test locations and acceptance range, where specified. |
Dimensional Reference Examples
| Outer Diameter (mm) | Wall Thickness (mm) | Reference length (m) |
| 12.7 | 1.65 | 6 |
| 25.4 | 2.11 | 6 |
| 50.8 | 3.05 | 6–12 |
| 76.2 | 4.19 | 6–12 |
| 101.6 | 5.74 | 6–10 |
Inconel 718 Forged Pipe Applications
Alloy 718 is used in demanding aerospace and oil-and-gas components. A pipe or hollow may be considered when strength, temperature and environmental requirements justify this alloy.
- Machined components: verify machining allowance and final heat-treatment requirements.
- High-strength tubular components: specify design loads, dimensions and inspection coverage.
- Pressure service: confirm material acceptance and design calculations under the applicable code.
UNS N07718 Forged Pipe PMI Test
Positive Material Identification (PMI) helps check alloy identity by measuring selected elements. The video illustrates a PMI inspection. Match the tested item to its heat identification and material certificate.
Inconel 718 Forged Pipe NDT Test
Non-destructive testing checks for specified discontinuities using an agreed technique. Ultrasonic testing can assess internal indications, while suitable surface methods address surface-breaking indications. Coverage and acceptance criteria must be defined for the order.
Inconel 718 Forged Pipe PT Test
Liquid penetrant testing (PT) reveals discontinuities open to the examined surface, such as cracks or laps. The photographs below illustrate penetrant inspection.
718 Nickel Alloy Forged Pipe Hardness Test
Hardness testing supports assessment of material condition and heat-treatment consistency. Specify the test method, scale, locations and acceptance criteria. Hardness readings alone do not replace required tensile testing.
UNS N07718 Forged Pipe Test Report
The existing report images below are examples of recorded sample identification and test results.
Inconel 718 Forged Seamless Pipe Why Choose Us
718 Forged Seamless Pipe Packing
Packaging should protect pipe surfaces and ends during handling and transport. Agree case or bundle construction, internal supports, corrosion protection and package markings for the shipment.
Pipe Dimensions: OD, ID and Wall Thickness
OD means outside diameter. WT means wall thickness. For a round pipe, ID = OD − 2 × WT. Use actual millimeter dimensions when calculating weight, rather than treating nominal pipe size as the measured diameter.
Inspection Requirements to Include in an RFQ
- Heat-specific chemical analysis and material identification.
- Tensile, yield and elongation tests required by the ordered condition.
- Hardness, where specified.
- Dimensional and visual examination.
- NDT or pressure testing as required by the product specification and purchase order.
Inconel 718 Pipe Weight Chart
The following theoretical weights use round-pipe geometry and a reference density of 8.19 g/cm³, approximately equivalent to the annealed density of 0.296 lb/in³ in the Special Metals technical bulletin.
| OD (mm) | Wall (mm) | Weight (kg/m) |
|---|---|---|
| 12.7 | 1.65 | 0.469 |
| 25.4 | 2.11 | 1.264 |
| 50.8 | 3.05 | 3.747 |
| 76.2 | 4.19 | 7.763 |
| 101.6 | 5.74 | 14.157 |
Formula: Weight (kg/m) = π × (OD − WT) × WT × 8.19 ÷ 1000. OD and WT are in millimeters. Multiply kg/m by length in meters for the theoretical weight of one length.
Nickel Alloy 718 Pipe Documentation
- Material certificate with heat number and applicable chemical and mechanical results.
- Dimensional and inspection records required by the purchase order.
- Heat-treatment records where required by the specification or quality plan.
- Packing list, commercial invoice and required origin or shipping documents.
Pressure Design Considerations for Alloy 718 Pipe
A safe working pressure cannot be assigned from the alloy name and pipe size alone. The calculation must use the applicable design code, design temperature, allowable stress for the accepted material condition, minimum wall after tolerance and allowances, and the complete piping arrangement.
For process piping, review the scope and requirements of ASME B31.3 where applicable.
Selecting the Correct Pipe Form
Useful distinctions when preparing an enquiry include thin-wall versus thick-wall dimensions, straight pipe versus a machined hollow, and solution-treated versus precipitation-hardened material. A nominal schedule or a general term such as “high pressure” is not a complete specification.
Send the actual OD, wall thickness, length, tolerance and drawing requirements. Welded tube, coiled tube and non-round sections are different product forms and should not be assumed equivalent to forged seamless pipe.
Surface Finish and Protection
Define the required inside and outside surface condition, roughness, cleanliness and end preparation in the enquiry. Any machining, polishing, pickling or protective coating requires technical confirmation for the specific product.
Inconel 718 Forged Seamless Pipe Tolerances
Dimensional inspection verifies the outside diameter, inside diameter and wall thickness against the ordered tolerances before the forged seamless pipe is released.
Specify OD, ID or wall tolerance, straightness, ovality, length tolerance and any machining allowance on the drawing or purchase order. The applicable standard and agreed dimensions determine acceptance.
