ss 304 seamless tube
2. Standard: ASTM A269, ASTM A213, engineered specifically for strict tolerance tubing configurations
3. Process: High-precision multi-pass cold drawing, ensuring highly uniform wall concentricity and smooth inner bore
4. Size Range: Small-diameter instrumentation sizes from 3mm up to 159mm outside diameter with precise decimals
5. Heat Treatment: Bright annealed (BA) in a hydrogen-protected environment to guarantee mirror-like internal cleanness
6. Surface Finish: High-purity bright annealed or external commercial polished (180/240/320/400 Grit)
7. Application: Laboratory testing systems, heat exchanger coils, food machinery piping, and hydraulic controls
8. Service Advantage: Flexible custom size fabrication, instant query responses, and complimentary sample availability
9. Packaging: Each tube individually sleeved in protective plastic bags, securely crated in solid export wooden frames
10. Key Advantage: Remarkable bending, flaring, and coiling capabilities, completely free of leaks under structural vibrations
SS 304 Seamless Tube – Premium Cold-Drawn Stainless Steel Tubing for High-Precision Industrial Applications
Hebei All Trust Steel Co., Ltd specializes in manufacturing high-precision ss 304 seamless tube engineered to meet the demanding requirements of instrumentation, heat exchange, and fluid control systems. Our tubes are manufactured using the latest multi-pass cold-drawing technologies to provide remarkable dimensional precision and high corrosion resistance. Our tubes are produced with an annual capacity of over 15.000 tons and 100% hydraulic testing with outer diameters from 1,59 mm up to 159 mm. Each is hydrogen-purged brilliant annealed (BA) to provide an ultra-smooth interior mirror surface that is perfect for laboratory testing systems, food processing pipes and hydraulic controls. And we have 5,000+ tons on hand for immediate delivery.
What Defines Our SS 304 Seamless Tube?
The product is a high-performance austenitic stainless steel solution that is produced without welded seams and joints. This results in consistent grain structure throughout with no heat-affected zone (HAZ) typical of welded equivalents.
You get remarkable structural stability with this grade of 18% chromium and 8% nickel. The seamfree structure overcomes major industrial issues such localised corrosion at weld points, the possibility of leaking under high pressures and a non-uniform wall thickness.
Our tubes have no longitudinal weld seam and can thus withstand 20% more operating pressure than welded tubes. Hence they are the ideal alternative for the transfer of fluids and gases when safety cannot be compromised.
Cold-drawing on precise mandrels ensures excellent concentricity between inner and outer diameters. Such homogeneity is required for precise instruments and intricate hydraulic assembly.
Technical Specifications
| Parameter | Details |
|---|---|
| Standard | ASTM A213 / A269 / ASME SA213 / EN 10216-5 |
| Material Grade | SS 304 (UNS S30400) |
| Manufacturing Process | Cold Drawn / Cold Rolled / Precision Rolled |
| Outer Diameter (OD) | 1/16" - 5" (1.59 mm - 127 mm) |
| Wall Thickness (WT) | 0.010" - 0.200" (0.25 mm - 5.08 mm) |
| Length Options | 5.8 m / 6 m / 11.8 m / 12 m / Custom Cut |
| Surface Finish | Bright Annealed (BA) / Solution Annealed / Mechanical Polished |
| End Type | Plain End / Square Cut / Burr-Free |
| Testing Methods | Eddy Current / Ultrasonic / Hydrostatic / Air Under Water |
| Mechanical Testing | Flaring / Flattening / Tensile / Hardness / PMI Analysis |
| Quality Certificates | EN 10204 3.1 & 3.2 MTC / ISO 9001:2015 / PED |
| Third-Party Inspection | SGS / BV / TUV / DNV / ABS Accepted |
| Packaging | Plywood Cases / Fumigated Wooden Boxes / Waterproof Wrapping |
Core Material Properties
The maximum carbon percentage of our seamless tubes is 0.08%, therefore reducing the carbide precipitation in welding processes. Density is 8.0 g/cm3 giving optimum ratio of strength to weight.
Mechanical properties include a minimum tensile strength of 515 MPa and minimum yield strength of 205 MPa. The elongation factor is 35% and so provides outstanding formability for bending and flaring operations.
Thermal Resistance Allows continuous operation up to 1795°F and intermittent exposure to 1590°F. The great resistance to oxidation means that the tubes are ideal for high temperature applications.
It has excellent cryogenic toughness and retains the mechanical qualities at sub-zero temperatures. This flexibility opens up a wider range of applications across temperature extremes.
Excellence in precision manufacturing
Each tube is subject to strict multi-stage quality inspection. We start with vendor audits and spectrographic examination of raw materials to check the chromium, nickel and molybdenum concentration versus standards.
Production monitoring involves dimensional inspection and real-time wall thickness verification. Our high-end cold drawing machine can achieve tolerances up to ±0.05 mm for precise applications.
Bright annealing in hydrogen purge gives an interior mirror surface devoid of scale. This ultra-smooth finish inhibits bacterial adherence in sanitary applications and lowers fluid friction in hydraulic systems.
The non-destructive testing procedures for the ss 304 seamless tube are 100% eddy current scanning and ultrasonic testing. Zero-leak performance is confirmed by air-under-water pressure testing prior to shipping.
Industrial Usage Scenarios
Oil & Gas Instrumentation The tube's ability to withstand severe hydrostatic pressure and corrosive saltwater conditions is advantageous for downhole control lines and offshore platform umbilical systems.
Food & Pharmaceutical Processing: Sanitary pipe systems include a smooth inside surface for simple CIP sterilisation. It is seamless, so there are no crevices for impurities to collect.
Aerospace & Automotive Hydraulics: Tubing used for high-pressure fuel lines and brake systems must be able to bear burst pressures exceeding 10,000 PSI and resist fatigue from vibration.
Heat Exchange Applications: In condenser and boiler applications, the high thermal conductivity of the tube is used. The same wall thickness is provided to provide uniform heat transfer efficiency.
Laboratory Testing Equipment: Analytical instruments and gas chromatography systems demand the dimensional precision and purity that only seamless construction provides.
Why Choose Hebei All Trust Steel?
We have partnerships with 15+ reputable steel mills to guaranty a steady supply of material and affordable price. We hold over 5,000 tons of rolling inventory to ensure fast order fulfilment.
Stock orders ship within 3-5 days, while custom specifications require just 15-20 days. Priority production scheduling can reduce manufacturing time by up to 35% for urgent projects.
Custom processing services include laser cutting, precision beveling, threading, and specialized length cutting. We accommodate flexible MOQ requirements for non-standard specifications.
Professional packing safeguards your investment in transportation worldwide. Each tube is individually protected with plastic sleeves, foam separators and strengthened plywood crating for seaworthy transit.
FAQ
Q：What structural performance parameters make this product ideal for precision instrumentation?
A：This tube offers exceptional dimensional concentricity and high microstructural ductility, providing reliable leak-free performance and excellent flexibility for complex high-pressure fluid control loops.
Q：How does your factory ensure the extremely smooth internal surface finish required for smooth flow dynamics?
A：The tube is precision cold-drawn over micro-tolerance mandrels and processed via hydrogen-purged bright annealing (BA) to lock in an ultra-smooth, scale-free internal mirror surface finish.
Q：What diagnostic leak-testing protocols must this specific tube batch clear prior to delivery?
A：Every manufacturing lot undergoes 100% mandatory non-destructive testing, passing through continuous online eddy current scans and comprehensive air-under-water pressure bubble tests.
Q：What precise micro-dimensional customization spectrums can be achieved to satisfy advanced industrial drafts?
A：We support extreme calibration versatility, accommodating micro-diameters down to 1/16 inch, tailored metric or fractional outer diameters, and specialized tight-tolerance wall profiles.
Q：Is this product suitable for welding applications?
A: Yes, but when you're welding heavy gauge, when intergranular corrosion is a problem, you want the 304L low-carbon version. Standard 304 works well in most structural welding applications.
Q: Why seamless and not welded for high pressure systems?
A: Seamless design removes weld decay problems and allows for a consistent wall thickness that can handle far greater internal burst pressures than welded alternatives.
Q: Processing over, is the tube magnetic?
A: It stays nonmagnetic in annealed condition. However, cold working methods might result in modest magnetism owing to austenite-to-martensite transition.
Q: How is this delicate instrumentation tubing wrapped to avoid surface scratches throughout worldwide transit?
A: The tubes are individually packaged in protective plastic sleeves, separated by soft foam, and fastened in strengthened, seaworthy plywood boxes so as to avoid any damage.
Contact Us
Ready to source premium ss 304 seamless tube for your project? Contact our technical team at info@hballtrust.com for customized solutions, material certificates, and competitive pricing tailored to your specifications.
