ISO9001 & SGS Certified | Since 2002 | 12,000 m² Factory | Ni Pipe Custom OD/WT | 15-25 Day Lead Time
High Purity Nickel Pipe for Aerospace — Customized Size, Seamless Options
Aircraft tubing carries more than fluid — it carries certification risk. A pipe that embrittles at altitude, corrodes in hydraulic fluid or fails its pressure test grounds a whole programme, not just a component. This high-purity nickel pipe is engineered for exactly that discipline: FCC structure with no ductile-to-brittle transition for low-temperature service, a passive film that resists hydraulic and de-icing environments, and seamless construction per ASTM B161. OD, wall thickness and length are customized to your drawing, so the tubing fits your line — not the other way around.
Available Sizes & Tolerances
| Dimension |
Range |
Note |
| Outside diameter |
per drawing |
Metric and inch series |
| Wall thickness |
per drawing |
Thin-wall to heavy-wall |
| Length |
per drawing |
Straight tubes, cut-to-length |
| Surface |
Bright annealed / pickled |
Per application |
| End finish |
Square-cut, deburred |
Per drawing |
Custom sizes are confirmed against the drawing before production; dimensional tolerances follow the applicable ASTM standard.
Key Advantages
- Seamless construction per ASTM B161 — no longitudinal weld seam to fail under pressure cycling.
- FCC crystal structure — no ductile-to-brittle transition, toughness retained at low temperature.
- High purity nickel (N4/N6/Ni200/Ni201) — stable passive film against hydraulic fluid, de-icing agents and salt-laden air.
- Customized OD, wall and length — metric and inch series, cut to your drawing.
- Free 0.5 kg sample & MOQ 5 kg — validate the pipe on your test bench before committing to a programme.
Technical Deep Dive
1. Seamless vs Welded — Why Seamlessness Matters at Altitude
Tubing is a pressure boundary: the weld seam is its weakest sentence. Seamless nickel pipe removes the longitudinal weld entirely, eliminating weld-zone property variation and the inspection burden that comes with it.
| Factor |
Seamless (ASTM B161) |
Welded |
| Longitudinal weld seam |
None |
Present |
| Pressure cycling behaviour |
Uniform properties around circumference |
Weld zone is the fatigue focus |
| Inspection |
Simpler certification path |
Weld NDE required |
| Aerospace preference |
Preferred for pressure lines |
Limited to low-pressure service |
2. Pressure Capability — Barlow Calculation (Example)
Allowable working pressure for thin-wall tube follows P = 2·S·t / D (Barlow formula). Example values below use S = 100 MPa as an assumed design stress — final allowable stress must follow your system code (e.g. ASME B31.3):
| OD |
Wall (t) |
P = 2·S·t / D (S = 100 MPa) |
| 6.35 mm (1/4 in) |
1.0 mm |
≈31.5 MPa |
| 6.35 mm (1/4 in) |
0.5 mm |
≈15.7 MPa |
| 12.7 mm (1/2 in) |
1.5 mm |
≈23.6 MPa |
| 12.7 mm (1/2 in) |
1.0 mm |
≈15.7 MPa |
Pressure rating scales linearly with wall thickness and inversely with diameter — a thicker wall buys pressure, a larger bore costs it.
3. Aerospace Material Behaviour — Low Temperature and Corrosion
FCC nickel keeps its toughness at sub-zero temperature where BCC steels turn brittle, and its passive film resists the fluids an aircraft tube meets in service.
| Requirement |
Nickel pipe response |
| Low-temperature toughness |
FCC — no ductile-to-brittle transition |
| Hydraulic / de-icing fluid exposure |
Stable passive film, corrosion resistant |
| Salt-laden air (coastal operation) |
Resistant to chloride pitting at high purity |
| Pressure cycling |
Seamless, uniform cross-section |
4. Applicable Standards
| Standard |
Scope |
| ASTM B161 |
Seamless nickel and nickel alloy pipe and tube |
| ASTM B163 |
Condenser and heat-exchanger tubes |
| ASTM B725 |
Welded nickel and nickel alloy pipe |
Standard selection depends on application; seamless B161 is the default for aerospace pressure lines.
Grade & Price Guide
| Grade |
Ni Content |
Best Application |
Reference Price (FOB, USD/kg) |
| N4 (NP1) |
≥99.9% |
Vacuum electronics |
420–480 |
| Ni201 |
≥99.0% |
High-temp service |
350–390 |
| Ni200 |
≥99.2% |
Battery, chemical |
340–380 |
| N6 (NP2) |
≥99.5% |
Industrial corrosion |
300–340 |
FOB China port, subject to size and quantity. Final quotation per drawing.
Chemical Composition
Source: DLX product catalogue, pure nickel family (grades N4 / N6 / Ni200 / Ni201).
| Element (wt%) |
N4 |
N6 |
Ni201 |
Ni200 |
| Ni+Co |
99.9 |
99.5 |
— |
— |
| Ni |
— |
— |
≥99.0 |
≥99.2 |
| C |
≤0.01 |
≤0.10 |
≤0.02 |
≤0.15 |
| Cu |
≤0.015 |
≤0.10 |
≤0.25 |
≤0.25 |
| Si |
≤0.03 |
≤0.10 |
≤0.35 |
≤0.35 |
| Mn |
≤0.002 |
≤0.05 |
≤0.35 |
≤0.35 |
| Fe |
≤0.04 |
≤0.10 |
≤0.40 |
≤0.40 |
| S |
≤0.001 |
≤0.005 |
≤0.01 |
≤0.01 |
| P |
≤0.001 |
≤0.002 |
— |
— |
| Mg |
≤0.01 |
≤0.10 |
— |
— |
Mechanical & Physical Properties (Annealed)
| Property |
Value |
| Density |
8.908 g/cm³ |
| Melting point |
1435–1446 °C |
| Curie temperature |
358 °C |
| Tensile strength (annealed) |
≥462 MPa |
| Elongation (annealed) |
≥35% |
| Hardness (annealed) |
90–120 HB |
| Shear modulus |
≈76 GPa |
| Electrical resistivity |
0.096 μΩ·m (20 °C) |
| Thermal conductivity (Ni200) |
70.2 W/m·K |
Product Specification
| Item |
Detail |
| Form |
Seamless straight tube, cut-to-length; welded on request |
| Dimensions |
OD, wall and length per drawing (metric / inch) |
| Temper |
Annealed (M) / half-hard / hard |
| Surface |
Bright annealed or pickled |
| End finish |
Square-cut, deburred |
| Packaging |
End caps + moisture barrier + wooden crate |
Quality Assurance
Pressure boundaries are verified, not assumed. Pipes are dimension-checked for OD, wall and ovality; hydrostatic or pneumatic testing follows the applicable standard, with eddy-current inspection on request. Chemical composition is locked per heat, batches are sampled for tensile and hardness, and an EN 10204 3.1 MTC is issued on request.
Packaging & Delivery
Tubes are end-capped to protect the bore, wrapped in moisture barrier film and packed in wooden crates; lot numbers trace back to the heat and melt record. Custom sizes are produced in 15–25 days, and free 0.5 kg samples are dispatched within 3–5 days.
About DLX Alloy
One mill, every form: Changzhou DLX Alloy draws, rolls and finishes nickel alloys in wire, strip, bar and tube form under one 12,000 m² roof — so an aerospace programme can source consistent chemistry across its entire bill of materials from a single nickel-only supplier. Since 2002, with ISO9001 and SGS certification and 1,200 tonnes of annual capacity, our process chain runs from melting to final inspection, and every lot carries traceability back to its heat.
FAQ
Q1. Seamless or welded — which should I specify?
For aerospace pressure lines, seamless per ASTM B161 removes the longitudinal weld seam and its fatigue focus. Welded (ASTM B725) is limited to low-pressure service.
Q2. What custom sizes can you supply?
OD, wall thickness and length per drawing, in metric or inch series, cut-to-length with square, deburred ends.
Q3. What are the MOQ and sample terms?
MOQ is 5 kg. A free 0.5 kg sample is available for N6 and Ni200; N4 and Ni201 samples are charged and refunded with your first order above 50 kg.
Q4. What testing and documentation do you provide?
Dimensional inspection, hydrostatic/pneumatic testing per standard, eddy-current on request, and an EN 10204 3.1 MTC with composition and mechanical results per batch.
Q5. Why is nickel pipe suited to aerospace?
FCC structure gives no ductile-to-brittle transition — toughness holds at low temperature — and the passive film resists hydraulic fluid, de-icing agents and salt-laden air.
