ASTM A333 Gr.6 Steel Pipe
Mar 06, 2024
- Chemical composition requirements, %,
C: ≤0.30
Mn: 0.29-1.06
P: ≤0.025
S: ≤0.025
Si: ≥0.10
Ni: ≤0.40
Cr: ≤0.30
Cu: ≤0.40
V: ≤0.08
Nb: ≤0.02
Mo: ≤0.12
*For every 0.01% reduction in carbon content, the manganese content can be increased by 0.05% until 1.35%.
*Based on protocol, niobium content may be increased to 0.05% for melt analysis and 0.06% for finished product analysis.
- Heat treatment requirements:
1. Normalizing above 815°C.
2. Normalize above 815°C, then temper.
3. Thermoforming between 845-945°C, then furnace cooling above 845°C (only applicable to seamless tubes).
4. Press 3 for processing and tempering.
5. Tempering after quenching above 815°C.
- Mechanical performance requirements:
Yield strength: ≥240Mpa
Tensile strength: ≥415Mpa
- Elongation：
|
Sample |
A333 GR.6 |
|
|
Portrait |
Horizontal |
|
|
Minimum value for standard circular specimens or small scale specimens with a gauge length of 4D |
22 |
12 |
|
For rectangular specimens with wall thicknesses 5/16 in. (7.94mm) and above, and all small specimens tested at full cross-section, the gauge length is 2 in. (50mm) |
30 |
16.5 |
|
For rectangular specimens with wall thickness less than 5/16 in. (7.94mm), the gauge length is 2 in. (50mm) (specimen width is 1/2 in., 12.7mm) |
A |
A |
A allows from the above elongation values, for wall thickness below 5/16in. (7.94mm), for every 1/32in. (0.79mm) thinning, the longitudinal elongation and transverse elongation decrease by 1.5%. Decrease by 1.0%.
- Impact test
Experimental temperature: -45°C
When a small-sized Charpy impact specimen is used and the specimen notch width is less than 80% of the actual thickness of the material, a lower impact test temperature should be calculated according to Table 6 of the ASTM A333 specification.
|
Sample, mm |
Minimum average of three samples | The minimum value among the three samples |
|
10 × 10 |
18 |
14 |
|
10 × 7.5 |
14 |
11 |
|
10 × 6.67 |
12 |
9 |
|
10 × 5 |
9 |
7 |
|
10 × 3.33 |
7 |
4 |
|
10 × 2.5 |
5 |
4 |
Steel pipes should be subjected to hydraulic or non-destructive testing (eddy current or ultrasonic) one by one.
Steel pipe outer diameter tolerance：
|
O.D, mm |
Positive tolerance,mm |
Negative tolerance,mm |
|
10.3-48.3 |
0.4 |
0.4 |
|
48.3＜D≤114.3 |
0.8 |
0.8 |
|
114.3＜D≤219.10 |
1.6 |
0.8 |
|
219.1＜D≤457.2 |
2.4 |
0.8 |
|
457.2＜D≤660 |
3.2 |
0.8 |
|
660＜D≤864 |
4.0 |
0.8 |
|
864＜D≤1219 |
4.8 |
0.8 |
