AISI 4130 / ASTM A519 alloy steel seamless tubes deliver high tensile strength, excellent fatigue resistance, and reliable impact toughness under high-stress operating conditions. Manufactured via hot-rolling or cold-drawing without welded seams, these tubes maintain uniform structural integrity across the entire cross-section. Supplied in normalized or quenched and tempered conditions, they machine, weld, and heat-treat predictably for critical structural and pressure applications.
Specifications
|
Primary Standards |
ASTM A519, AISI 4130, SAE J1352 |
|
Cross-Reference Standards |
EN/DIN 1.7214, JIS SCM430 |
|
Manufacturing Processes |
Hot Finished (HF) & Cold Drawn (CD) |
|
Outer Diameter (OD) |
10 mm – 320 mm (0.39 in – 12.6 in) |
|
Wall Thickness (WT) |
1 mm – 50 mm (0.04 in – 1.97 in) |
|
Length |
Random lengths (5m–7m) or fixed lengths up to 12m |
|
Heat Treatment States |
Normalized (+N), Annealed (+A), Quenched & Tempered (+QT) |
|
Surface Condition |
Black, pickled, oiled, phosphated, or cold-drawn bright finish |
Material & Manufacturing
Chemical Composition (ASTM A519 / AISI 4130 %)
|
Carbon (C) |
0.28 – 0.33 |
|
Chromium (Cr) |
0.80 – 1.10 |
|
Molybdenum (Mo) |
0.15 – 0.25 |
|
Manganese (Mn) |
0.40 – 0.60 |
|
Silicon (Si) |
0.15 – 0.35 |
|
Phosphorus (P) |
max 0.035 |
|
Sulfur (S) |
max 0.040 |
Production Process
• Billet Piercing: Round steel billets are heated to 1200°C and pierced on rotary piercing mills to form a hollow shell.
• Elongation & Sizing: The hollow shell passes through mandrel mills or stretch-reduction mills to achieve target OD and wall thickness.
• Cold Drawing (Optional): Tubes undergo pickling and cold drawing through tungsten carbide dies for tight dimensional tolerances and smooth surface finishes.
• Controlled Heat Treatment: Continuous roller-hearth furnaces execute precise normalization or quenching and tempering cycles to lock in mechanical properties.
Quality Inspection
Every production lot undergoes rigorous destructive and non-destructive testing prior to shipment:
Dimensional Verification: Laser micrometers measure OD, ID, and wall thickness consistency along the entire tube length.
Non-Destructive Examination (NDE): 100% Eddy Current or Ultrasonic testing detects internal laminations, surface seams, and micro-cracks.
Mechanical Testing: Tensile testing, yield strength verification, elongation measurement, and Rockwell/Brinell hardness testing per ASTM A519.
Metallographic Analysis: Grain size and decarburization depth evaluation under optical microscopes.
Documentation: EN 10204 3.1 Mill Test Certificate provided with every shipment, detailing exact heat analysis and mechanical test results.
Applications
Aerospace: Fuselage structures, engine mounts, and landing gear components.
Motorsports: Roll cages, chassis frames, and suspension pushrods.
Oil & Gas: Downhole tools, drill string components, and high-pressure fluid lines.
Heavy Machinery: Hydraulic cylinders, drive shafts, and high-load structural pins.
Customization & Supply
Dimensional Customization:
Non-standard outer diameters and wall thicknesses available upon request.
Length Cutting:
Precision cutting to exact fixed lengths with deburred ends.
Packaging:
Bundle packing with plastic caps, woven bags, or wooden crating to prevent transit damage.
Lead Time:
25–35 days for standard production runs; expedited delivery options available for stocked specifications.
FAQ
Q: What is the difference between hot-finished and cold-drawn 4130 seamless tubes?
A: Hot-finished tubes suit structural applications requiring larger diameters and thicker walls with standard tolerances. Cold-drawn tubes offer tighter dimensional tolerances, smoother surface finishes, and higher yield strength, making them ideal for precision machining and hydraulic systems.
Q: Can 4130 alloy steel tubes be welded directly?
A: Yes, but pre-heating (typically 150°C to 200°C) and post-weld heat treatment are recommended to prevent cracking in the heat-affected zone due to the medium-carbon and alloy content.
Q: Are Mill Test Certificates (MTC) supplied with the order?
A: Every order includes an EN 10204 3.1 Mill Test Certificate tracing chemical composition, heat number, and mechanical test results back to the original steel melt.
Q: What is the typical minimum order quantity (MOQ)?
A: MOQ depends on the specification. Standard sizes start at 1 metric ton per item, while custom dimensions or non-standard heat treatments require individual evaluation based on rolling schedules.
Q: What protective coatings are applied for ocean freight?
A: Tubes are coated with anti-rust oil, fitted with plastic pipe end protectors, and bundled with steel strapping, followed by woven plastic wrapping to withstand moisture during maritime shipping.
Q: Can you perform third-party inspection (TPI)?
A: Yes. We accommodate inspection by SGS, BV, TUV, or any client-designated third-party agency prior to final release.
Request a Quote
Submit your specifications to receive a formal quotation within 24 hours.
Required Parameters: Outer Diameter (OD), Wall Thickness (WT), Length, Steel Grade (ASTM A519 / AISI 4130), Quantity, and Destination Port.
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