ASME SA790 / ASTM A790 Duplex Steel Pipe | UNS S31803, UNS S32205
June 17, 2024
12Cr1MoV High Pressure Alloy Steel Boiler Pipe
June 30, 2024
ASTM A249 Stainless Steel Boiler Tubes
ASTM A249 covers welded austenitic stainless steel boiler, superheater, heat exchanger, and condenser tubes. These tubes are designed for high-temperature and general corrosive service.
Key Specifications
- Standard: ASTM A249
- Material: Austenitic stainless steels
- Form: Welded tubes
- Applications: Boilers, superheaters, heat exchangers, condensers
Chemical Composition
The chemical composition varies depending on the specific grade of stainless steel used. Below are typical compositions for common grades:
| Element | TP304 (%) | TP316 (%) | TP321 (%) |
|---|---|---|---|
| Carbon (C) | ≤ 0.08 | ≤ 0.08 | ≤ 0.08 |
| Manganese (Mn) | ≤ 2.00 | ≤ 2.00 | ≤ 2.00 |
| Phosphorus (P) | ≤ 0.045 | ≤ 0.045 | ≤ 0.045 |
| Sulfur (S) | ≤ 0.030 | ≤ 0.030 | ≤ 0.030 |
| Silicon (Si) | ≤ 1.00 | ≤ 1.00 | ≤ 1.00 |
| Chromium (Cr) | 18.0 – 20.0 | 16.0 – 18.0 | 17.0 – 19.0 |
| Nickel (Ni) | 8.0 – 11.0 | 10.0 – 14.0 | 9.0 – 12.0 |
| Molybdenum (Mo) | – | 2.0 – 3.0 | – |
| Titanium (Ti) | – | – | 5(C+N) – 0.70 |
Mechanical Properties
| Property | TP304 | TP316 | TP321 |
|---|---|---|---|
| Tensile Strength (min) | 515 MPa (75 ksi) | 515 MPa (75 ksi) | 515 MPa (75 ksi) |
| Yield Strength (min) | 205 MPa (30 ksi) | 205 MPa (30 ksi) | 205 MPa (30 ksi) |
| Elongation (min) | 35% | 35% | 35% |
| Hardness (max) | 90 HRB | 90 HRB | 90 HRB |
Weight Chart
| Outer Diameter (OD) (mm) | Wall Thickness (mm) | Weight (kg/m) |
|---|---|---|
| 12.7 | 1.24 | 0.355 |
| 19.05 | 1.65 | 0.698 |
| 25.4 | 2.11 | 1.270 |
| 38.1 | 2.77 | 2.284 |
| 50.8 | 3.05 | 3.593 |
| 76.2 | 3.40 | 6.342 |
Pressure Rating
Pressure ratings depend on the tube dimensions and operating conditions. Below are typical pressure ratings for common sizes at room temperature:
| Tube Size (OD x Wall) (mm) | Pressure Rating (psi) |
|---|---|
| 12.7 x 1.24 | 2,900 |
| 19.05 x 1.65 | 2,200 |
| 25.4 x 2.11 | 1,800 |
| 38.1 x 2.77 | 1,500 |
| 50.8 x 3.05 | 1,300 |
| 76.2 x 3.40 | 1,100 |
Note: These values are indicative and can vary based on the specific grade and temperature conditions.
Tolerances
| Dimensions | Tolerance Range |
|---|---|
| Outside Diameter (OD) | ±0.10 mm for OD ≤ 25.4 mm |
| ±0.15 mm for 25.4 mm < OD ≤ 38.1 mm | |
| ±0.25 mm for OD > 38.1 mm | |
| Wall Thickness | ±10% |
| Length | Up to 6.0 m ±6.0 mm |
| Ovality | 2% of OD for thin-wall tubes |
| Straightness | 1/8 inch in any 10-foot length |
Price List
The price of ASTM A249 stainless steel boiler tubes can vary based on factors such as grade, size, wall thickness, and market conditions. Below is a general price range for some common sizes and grades:
| Grade | Size (OD x Wall) (mm) | Price (USD per meter) |
|---|---|---|
| TP304 | 12.7 x 1.24 | $10 – $15 |
| TP304 | 19.05 x 1.65 | $15 – $20 |
| TP316 | 25.4 x 2.11 | $20 – $25 |
| TP316 | 38.1 x 2.77 | $25 – $30 |
| TP321 | 50.8 x 3.05 | $30 – $40 |
| TP321 | 76.2 x 3.40 | $40 – $50 |
Note: Prices are indicative and can fluctuate based on material costs, supplier, and order quantity.
Types of ASTM A249 Steel Tubes
- TP304 Stainless Steel Tubes:
- Composition: 18% Chromium, 8% Nickel
- Applications: General-purpose use, good corrosion resistance
- TP316 Stainless Steel Tubes:
- Composition: 16% Chromium, 10% Nickel, 2% Molybdenum
- Applications: Enhanced corrosion resistance, particularly against chlorides and industrial pollutants
- TP321 Stainless Steel Tubes:
- Composition: 18% Chromium, 9% Nickel, Ti stabilized
- Applications: High-temperature environments, good resistance to intergranular corrosion
- TP347 Stainless Steel Tubes:
- Composition: 18% Chromium, 10% Nickel, Nb stabilized
- Applications: High-temperature resistance, particularly against carbide precipitation
Conclusion
ASTM A249 stainless steel boiler tubes are essential in various high-temperature and corrosive environments. Understanding their specifications, chemical composition, mechanical properties, and applications can help in selecting the right type of tube for your specific needs. Whether you’re looking for durability, corrosion resistance, or mechanical strength, these tubes offer a versatile solution for industrial applications.
Related posts
The service temperature is 580 ℃, and the steel plate is required to have high high temperature endurance strength. The steel plate is delivered in the normalized and tempered state. 12Cr1MoVG alloy pipe is based on high-quality carbon structural steel, and one or several alloy elements are appropriately added to improve the mechanical properties, toughness and hardenability of the steel.
ASTM A554 specification covers ferritic, welded austenitic and austenitic-ferritic duplex stainless steel mechanical tubing intended for use in structural, ornamental, exhaust and other applications where mechanical properties, appearance, or corrosion resistance is needed. ASME SA554 Tubing is commonly shipped without protective coating. ASTM A554 specification covers as welded or cold-reduced mechanical tubing in sizes to 16 inch (406.4 mm) outside dimension and in wall thicknesses 0.020 inch (0.51 mm). ASTM A554 Welded Mechanical Tubing made from flat-rolled steel by an automatic welding process without the addition of filler metal. ASTM A554 Tubes furnished in one of the following shapes – square, round, rectangular, or special.
Duplex-grade stainless steel alloys have ferritic/austenitic properties, giving these materials superior strength and excellent resistance to oxidation. While the duplex-grade family includes a wide range of specific formulations, duplex S31803 (2205) and super duplex S32750 (2507) stainless steel are two of the most common. These stainless steel products are extremely versatile, with many applications in the oil and gas, petrochemical, and chemical processing industries.
S31803 is the Unified Numbering System (UNS) designation for the original duplex stainless steel. The UNS system was created by a number of trade groups working together in the 1970’s, to reduce confusion from the same alloy being called different things or vice-versa. Each metal is indicated by a letter followed by five numbers, where the letter indicates the family of metals i.e. S for stainless steels.
Alloy 347 stainless steel belongs to the family of austenitic stainless steels and is known for its exceptional stability due to the presence of stabilizing elements. This alloy is highly weldable, and in most cases, annealing is not necessary after welding unless stress relief is desired. The remarkable resistance to oxidation and corrosion exhibited by 347 stainless steel makes it a reliable choice for various applications. Its high creep strength allows it to perform optimally at temperatures up to 1600 °F.
