ASTM A249 316L refers to TP316L austenitic stainless steel welded tube conforming to the ASTM A249 standard. It is made of low-carbon molybdenum stainless steel and is specifically designed for use in pressure equipment such as boilers, heat exchangers, and condensers. 316L is a low-carbon (≤0.03%) stainless steel grade containing molybdenum (2–3%), which significantly enhances resistance to chloride pitting and crevice corrosion and improves intergranular corrosion resistance in welded joints. ASTM A249 316L welded tubes are typically manufactured using resistance welding (ERW) or TIG welding and undergo solution annealing.
Typical applications for ASTM A249 316L welded tubes include the petrochemical, pharmaceutical, food processing, and offshore engineering industries, as well as high-temperature, high-pressure heat exchange systems; they are particularly suitable for environments containing chloride ions or corrosive media.
ASTM A249 316/316L Tube Specifications
| Standard | ASTM A249, ASME SA249 |
|---|---|
| Material | 316/316L stainless steel |
| Tube Type | Welded Tube |
| Finishes | Annealing Pickling, Bright Annealing |
| Outside Diameter | 6 Up To 304.8 Mm |
| Thickness | 0.5 Up To 6 Mm |
| Application | Heat Exchanger System |
ASTM A249 316/316L Stainless Steel Chemical Composition, %, Max
| C | Mn | P | S | Si | Ni | Cr | Mo | Fe | |
|---|---|---|---|---|---|---|---|---|---|
| 316 | 0.08 | 2.00 | 0.045 | 0.030 | 1.0 | 11-14 | 16-18 | 2-3 | Balance |
| 316L | 0.035 | 2.00 | 0.045 | 0.030 | 1.0 | 10-14 | 16-18 | 2-3 | Balance |
ASTM A249 316/316L Stainless Steel Properties
| Tensile Strength(Mpa), Min | Yield Point(Mpa), Min | Elongation(%), Min | Hardness, Max | |
|---|---|---|---|---|
| 316 | 515 | 205 | 35 | B90 |
| 316L | 485 | 170 | 35 | B90 |
A249 316 316L Stainless Steel Tube Manufacturing
Nowadays, with the development of technology in welded stainless steel tube, in many circumstances, the seamless tube can be replaced by a welded tube for the same purpose. for the A249 stainless steel welded tube, we focus on heat treatment, seam welding of important process in the welded tube production, and excellent corrosion performance.
TIG Welding & Welding Seam
TIG welding can effectively isolate from the surrounding air, not reaction, the arc in the process of tungsten argon arc welding and automatic removal of the role of the surface oxide film. The welding bead will be removed, and cold drawing will be made, and good corrosion performance.
Heat Treatment
Solution annealing is an important stage in the process of welding stainless steel tube, after full solution annealing, the tube will be soft and easy to form and fabrication, such as stainless steel U bending tube, stainless steel coiled tube, solution annealing will remove alloy segregation, and grains will recrystallize as a development of becoming stress relief. We will be concerned about annealing temperature and time depending on which stainless steel grade.
ASTM A249 Tolerances
| OD | WTH | L | |
|---|---|---|---|
| ＜25.40mm | ±0.10mm | ±10.00% | OD＜50.8mm +3.0mm -0mm OD≥50.8mm +5.0 -0mm |
| ≥25.4mm~38.1mm | ±0.15mm | ||
| ≥38.1mm~50.8mm | ±0.20mm | ||
| ≥50.8mm~63.5mm | ±0.25mm | ||
| ≥63.5mm~76.2mm | ±0.30mm | ||
| ≥76.2mm~101.6mm | ±0.38mm | ||
| ≥101.6mm~190.5mm | +0.38mm -0.64mm | ||
| ≥190.5mm~228.6mm | +0.38mm -1.14mm | ||
Testing Of A249 316 316L Stainless Steel Tube
Standard Testing
- Tensile Strength
- Flattening test
- Flaring test
- Flange test
- Dimensional
- PMI
- Hardness test
- Eddy Current test
Optional Testing
- Ultrasonic
- Hydrostatic
- Air Under Water
- Grain Size
- Corrosion
- radiographic inspection
- weld decay test
A249 316L Tube Dimensions
| OD/WT (Mm) | 0.5 | 0.6 | 0.7 | 0.8 | 0.9 | 1.0 | 1.2 | 1.5 | 1.65 | 2.0 | 2.11 | 2.5 | 3.0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 12.7 | Y | Y | Y | Y | Y | Y | Y | ||||||
| 14 | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||||
| 15 | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||||
| 16 | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||||
| 19.1 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||
| 20 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||
| 22 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||
| 23 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||
| 25.4 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | |
| 28 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | |
| 30 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | |
| 31.8 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | |
| 34 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | |
| 35 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||
| 38.1 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||
| 40 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | |||
| 42.2 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | |||
| 44.5 | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | |||
| 50.8 | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||||
| 60.3 | Y | Y | Y | Y | Y | Y | Y | Y | |||||
| 63.5 | Y | Y | Y | Y | Y | Y | Y | Y | |||||
| 76.2 | Y | Y | Y | Y | Y | Y | Y | ||||||
| 88.9 | Y | Y | Y | Y | Y | Y | Y | ||||||
| 101.6 | Y | Y | Y | Y | Y | Y | Y |
