SA213 T5 Seamless Alloy Steel Tube – ASTM A213 / ASME SA213 Standard for Boiler, Superheater and Heat Exchanger – 5% Chromium-0.5% Molybdenum Ferritic Alloy Tube for High-Temperature and Corrosive Service

Premium SA213 T5 Seamless Alloy Tube for Refinery Heaters, High-Temperature Boilers, Heat Exchangers, and Petrochemical Furnaces

Womic Steel produces high-quality SA213 T5 Seamless Alloy Steel Tube, manufacturing chromium-molybdenum (5Cr-0.5Mo) ferritic alloy tubes in accordance with ASTM A213 / ASME SA213 specifications. Our SA213 T5 tubes meet the demanding requirements of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, with a minimum tensile strength of 415 MPa and excellent resistance to high-temperature sulfidation and oxidation at temperatures up to 650°C (1200°F). These seamless alloy tubes are the ideal choice for refinery heaters, furnace tubes, heat exchangers, and high-temperature petrochemical applications where resistance to hot corrosion and oxidation is critical, and where lower chromium grades like T11 or T22 are insufficient.

Manufacturer: Womic Steel

1. Product Definition and Scope

SA213 T5 (UNS K41545) is a seamless ferritic alloy steel tube specified under ASTM A213 / ASME SA213 for use in boilers, superheaters, heat exchangers, and other high-temperature pressure-containing equipment. The “T5″ designation indicates a nominal composition of 5% chromium and 0.5% molybdenum. T5 provides significantly better oxidation and sulfidation resistance than lower chromium grades (T1, T2, T11, T22) while maintaining good creep strength. It is widely used in refinery heaters, catalytic reforming units, and high-temperature furnace tubes where exposure to sulfur-bearing fuels requires enhanced corrosion resistance.

Manufacturing Process: T5 tubes are manufactured by the seamless process (hot-finished or cold-finished). Due to the higher chromium content (5%), T5 has greater hardenability than lower Cr grades and requires careful heat treatment (full annealing or normalize and temper) to achieve the proper microstructure and mechanical properties. T5 is typically supplied in the annealed condition.

Grade Designation:

Equivalent Standards and Grades:

Manufacturer: Womic Steel

2. Chemical Composition Requirements

The chemical composition of SA213 T5 is balanced with 5% chromium to provide excellent oxidation and sulfidation resistance while 0.5% molybdenum contributes to creep strength.

SA213 T5 Chemical Composition (Heat Analysis – Seamless Tube):

Composition Notes:

T5 is often selected for refinery service where fuels contain sulfur. The 5% Cr level offers good resistance to sulfidation attack, which is a common failure mode in heater tubes fired with high-sulfur fuels. For even more severe corrosion (vanadium attack, molten salts), higher chromium grades (T9, T91) are recommended.

3. Mechanical Properties

The mechanical properties of SA213 T5 are similar to other CrMo grades at room temperature but maintain good strength at elevated temperatures.

Tensile Requirements (Room Temperature):

For thin walls, elongation adjustment follows the same formula as other SA213 grades.

Hardness Requirements:

High-Temperature Tensile Properties (Reference Values):

Creep Rupture Strength (Typical Values):

The creep strength of T5 is adequate for most refinery heater applications. Its primary advantage over lower chromium grades is not higher creep strength but superior resistance to hot corrosion and sulfidation at elevated temperatures.

4. Heat Treatment Requirements

T5 steel tubes require proper heat treatment to achieve the required microstructure (ferritic-pearlitic or bainitic depending on cooling rate). Due to the higher chromium content, T5 has higher hardenability than T11/T22.

Heat Treatment Requirements:

Normalizing followed by tempering is the most common treatment, producing a fine-grained ferritic microstructure with carbides. Tempering temperature should be at least 650°C (1200°F) to soften and improve ductility.

Manufacturer: Womic Steel performs heat treatment in accordance with ASTM A213 / ASME SA213 requirements. Heat treatment certificates are available upon request.

5. Dimensional Tolerances

Dimensional tolerances for T5 tubes follow ASTM A213 / A1016 as described for other grades.

● Cold Drawn OD Tolerances: Same as T11/T22.

● Wall Thickness Tolerances (Cold Drawn): ±10% of nominal.

● Hot Finished Tolerances: Follow the sliding scale.

● Straightness: 0.2% of length (2 mm/m).

● Length Tolerances: Random 5-12 m; specific lengths +50-100 mm / -0.

6. Available Sizes and Specifications

T5 tubes are available in the same size ranges as other SA213 grades.

Typical Size Range:

● Cold Finished: OD 6.35 mm (1/4″) to 101.6 mm (4″)

● Hot Finished: OD 12.7 mm (1/2″) to 219.1 mm (8-5/8″)

● Wall Thickness: 1.6 mm to 15 mm depending on size

Common T5 Tube Sizes (OD x WT in mm):

25.4 x 2.5, 31.8 x 3.0, 38.1 x 3.5, 44.5 x 4.0, 50.8 x 4.0, 50.8 x 5.0, 60.3 x 5.0, 63.5 x 5.0, 76.2 x 6.0, 88.9 x 6.0, 101.6 x 8.0, 114.3 x 8.0, 141.3 x 10.0

Manufacturer: Womic Steel maintains inventory of common T5 tube sizes for refinery and petrochemical applications.

7. Inspection and Testing Requirements

Standard SA213 tests apply:

NDT Methods: Eddy current (ECT) or ultrasonic (UT) as specified. Hydrostatic testing is also accepted.

8. Applications

SA213 T5 tubes are primarily used in refinery and petrochemical high-temperature corrosive service.

T5 is particularly valued for its resistance to sulfidation attack from sulfur-bearing fuels. It is a standard material for many refinery heater tubes (API 530). For temperatures below about 540°C (1000°F), T11 may suffice, but for higher temperatures or higher sulfur fuels, T5 is preferred.

9. Comparison with Other Grades

T5 occupies a middle ground between the low-chromium grades (T11/T22) and the 9Cr grades. It provides significant corrosion resistance improvement over T22 without the higher cost and weldability challenges of T9.

10. Welding Procedure for SA213 T5

T5 has high hardenability and is susceptible to cold cracking. Strict preheat and PWHT are mandatory.

Recommended Welding Processes: GTAW (TIG) preferred for root pass; SMAW with low-hydrogen electrodes for fill and cap.

Recommended Filler Metals:

Critical Welding Requirements:

PWHT must be performed immediately after welding to prevent hydrogen cracking. The high chromium content makes the weld metal and HAZ hard and susceptible to delayed cracking if proper heat treatment is not applied.

11. Traceability and Marking

Each tube is stencil marked with:

● Manufacturer name

● ASTM A213 / ASME SA213 T5

● UNS K41545

● Size (OD x WT)

● Heat number

● Length

NDT method

Marking Example:

12. Quality Documents

● Mill Test Report (EN 10204 Type 3.1) – included

● Heat Treatment Certificate – included

● Hydrostatic/NDT Certificate – included

● Dimensional Inspection Report – includedCertificate of Origin – included

● Third-Party Inspection – optional (SGS, BV, DNV, TUV, LR, ABS)

13. Contact Information

Website: www.womicsteel.com

E-mail: sales@womicsteel.com

Tel / WhatsApp / WeChat:

Victor: +86 15575100681

Jack: +86 18390957568

Womic Steel – Your reliable partner for SA213 T5 seamless alloy tubes, stainless steel products, and custom solutions for refinery, petrochemical, boiler, and high-temperature furnace applications.