Seamless Boiler Tube ASTM Certified Mill Direct | Kuaima Steel Group
Supplier's customization ability
- Drawing-based customization
- Sample-based customization
- Full customization
Minimum order quantity: 1 ton
Shipping total: To be negotiated
- Lead time:
- confirmed with the quotation
- Packaging:
- standard export packing
- Samples:
- available on request
Product details
Technical Specifications of Seamless Boiler Tube
| Property | Parameter | Description |
|---|---|---|
| Product Name | Seamless Boiler Tube | Hot-rolled or cold-drawn seamless steel tube for boiler and heat exchanger service |
| Material Grade | ASTM A106 Gr.B / SA210 Gr.A1 / SA213 T11 / T22 / 20G | Multiple grades available for medium- and high-pressure boiler applications |
| Standard Compliance | ASTM A106, ASTM A210, ASTM A213, EN 10216-2, GB 5310, JIS G3461 | Meets international boiler tube manufacturing and testing standards |
| Carbon (C) | 0.10 – 0.30% | Varies by grade; ensures adequate strength and weldability |
| Manganese (Mn) | 0.29 – 1.06% | Enhances tensile strength and hardenability |
| Silicon (Si) | ≤ 0.50% | Acts as deoxidizer and improves high-temperature oxidation resistance |
| Chromium (Cr) | 0 – 2.50% | Present in alloy grades (T11/T22) for creep and oxidation resistance |
| Molybdenum (Mo) | 0 – 1.05% | Improves elevated-temperature strength in alloy grades |
| Phosphorus (P) / Sulfur (S) | P ≤ 0.035% / S ≤ 0.035% | Controlled to minimize hot shortness and ensure toughness |
| Tensile Strength | 415 – 590 MPa | Per ASTM A106 Gr.B ≥ 415 MPa; alloy grades up to 590 MPa |
| Yield Strength | 205 – 310 MPa | Per ASTM A106 Gr.B ≥ 240 MPa; varies with grade and heat treatment |
| Elongation | ≥ 22% | Minimum elongation in 50 mm gauge length per applicable standard |
| Dimensions (OD × WT × Length) | OD: 10.2 – 457 mm / WT: 1.5 – 50 mm / L: 4 – 18 m | Custom sizes available; tolerances per ASTM A450 or EN 10216-2 |
| Surface Finish | Black painted / Oiled / Varnished / Bare | Anti-rust treatment applied; pickled or shot-blasted finish optional |
| Application | Power plant boilers, superheaters, reheaters, economizers, heat exchangers | Suitable for medium- and high-pressure steam service up to 600 °C |
| Certification | ISO 9001, PED 2014/68/EU, TÜV, BV, SGS, Lloyd's | Mill test certificate EN 10204 3.1 / 3.2 provided with each shipment |
| Packaging | Bundled with steel strips, plastic caps on ends, waterproof wrapping | Seaworthy export packaging; marking per customer or standard requirement |
| MOQ | 1 Metric Ton | Smaller trial orders negotiable; lead time depends on specification |
Seamless Boiler Tube ASTM Certified Mill Direct | Kuaima Steel Group
Seamless boiler tube is an essential component in power generation, petrochemical processing, and industrial heating systems where reliable performance under high temperature and pressure is non-negotiable. Manufactured through hot-rolling or cold-drawing processes without any welded seam, these tubes deliver superior structural integrity that welded alternatives simply cannot match. At Kuaima Steel Group, we supply ASTM-certified seamless boiler tubes directly from our partner mills, offering premium grade materials at cost-effective, mill-direct rates. Whether you operate coal-fired power plants, waste heat recovery boilers, or high-pressure steam generators, our seamless boiler tubes meet the rigorous demands of continuous service in extreme thermal environments.
What Is Seamless Boiler Tube?
A seamless boiler tube is a hollow cylindrical steel product manufactured from a solid round billet that is pierced and elongated without any longitudinal weld joint. This seamless construction eliminates the weakest point found in welded tubes — the seam — resulting in uniform grain structure and consistent wall thickness throughout the entire length. Seamless boiler tubes serve critical roles in water-tube boilers, superheaters, economizers, and reheater sections where they must withstand internal pressures exceeding 20 MPa and continuous operating temperatures up to 580°C (1076°F). The absence of a weld seam provides enhanced resistance to creep, fatigue, and stress corrosion cracking under prolonged high-temperature service.

Seamless Boiler Tube Technical Specifications
Our seamless boiler tubes are manufactured in compliance with internationally recognized standards, ensuring traceability and performance reliability across all critical boiler applications.

| Parameter | Specification Details |
|---|---|
| Applicable Standards | ASTM A106 Grade B/C, ASTM A179, ASTM A192, ASTM A210 Grade A1/C, ASME SA213 T11/T22/T91, EN 10216-2, GB 5310 |
| Steel Grades | 20G, 15CrMoG, 12Cr1MoVG, SA106B, SA210C, T11, T22, T91, 16Mo3, 13CrMo4-5 |
| Outside Diameter | 10.0 mm – 630 mm (0.394″ – 24.8″) |
| Wall Thickness | 1.5 mm – 60 mm (0.059″ – 2.362″) |
| Length | Random length 5–12 m, or cut-to-length per customer requirement |
| Tensile Strength | 415 MPa min (SA192) / 485 MPa min (SA210 Gr.A1) / 585 MPa min (SA213 T91) |
| Yield Strength | 240 MPa min (SA192) / 255 MPa min (SA210 Gr.A1) / 415 MPa min (SA213 T91) |
| Max Service Temperature | Up to 580°C (T91 grade) / 565°C (T22 grade) / 400°C (SA192 carbon steel) |
| Surface Finish | Black painted, varnished, oiled, or bare as specified |
| Testing | Hydrostatic test, flattening test, flaring test, ultrasonic examination per ASTM E213, eddy current per ASTM E309 |
Key Advantages of Our Seamless Boiler Tubes
Uniform Microstructure: The piercing and elongation process produces a homogeneous grain flow aligned along the tube axis, delivering a density of approximately 7.85 g/cm³ with no weld-induced heat-affected zones. This translates to consistent mechanical properties across every section of the tube.

Outstanding High-Temperature Performance: Alloy grades such as SA213 T91 (9Cr-1Mo-V) maintain a minimum tensile strength of 585 MPa at room temperature and exhibit exceptional creep rupture resistance at temperatures up to 580°C, enabling thinner wall designs and reduced overall boiler weight.
Comprehensive Non-Destructive Testing: Every seamless boiler tube from Kuaima Steel Group undergoes 100% ultrasonic testing per ASTM E213 and hydrostatic testing at pressures calculated per ASTM A530, ensuring zero-defect delivery for critical pressure service.
Dimensional Precision: Our tubes are supplied with outer diameter tolerances within ±0.5% and wall thickness tolerances within ±10% (or tighter per special order), meeting the precise fit-up requirements of modern boiler fabrication.
Applications
Seamless boiler tubes find extensive application in:
- Utility and industrial water-tube boilers (subcritical and supercritical)
- Superheater and reheater sections operating above 450°C
- Economizer tubes for heat recovery systems
- Petrochemical furnace tubes and heat exchangers
- Combined cycle heat recovery steam generators (HRSG)
- Nuclear power steam supply systems (with appropriate nuclear grade certification)
Frequently Asked Questions
What is the MOQ?
Our minimum order quantity for seamless boiler tubes is typically 1 metric ton per size and grade combination. For less common alloy grades such as T91 or T92, a minimum of 2 metric tons may apply depending on mill scheduling.
Do you provide material test certificates?
Yes. Every shipment includes original mill test certificates (MTC) per EN 10204 3.1, documenting chemical composition, mechanical properties, and non-destructive test results. Third-party inspection reports from SGS, TÜV, or BV are available upon request at additional cost.
What is the typical delivery time?
Standard carbon steel grades (SA192, SA210) in common sizes ship from stock within 7–10 business days. Alloy grades (T11, T22, T91) and non-standard dimensions require 30–45 days for mill production and quality inspection.
Can you cut to custom sizes?
Absolutely. We offer precision cut-to-length services with a tolerance of ±3 mm, along with beveling (30° or 37.5° per ASME B16.25), threading, and protective end-cap installation to meet your project-specific fabrication requirements.
Get a Competitive Quote for Seamless Boiler Tube
Kuaima Steel Group delivers ASTM and ASME certified seamless boiler tubes at mill-direct rates with full traceability and technical support. Contact our dedicated boiler tube specialists today with your required grade, dimensions, and quantity. We respond to all inquiries within 12 hours with detailed pricing and lead time confirmation — helping you keep your boiler projects on schedule and on budget.
Ratings & Reviews
Know your supplier
Supplier's customization ability
- Drawing-based customization
- Sample-based customization
- Full customization
Minimum order quantity: 1 ton
Shipping total: To be negotiated
- Lead time:
- confirmed with the quotation
- Packaging:
- standard export packing
- Samples:
- available on request