P355QL2 and P460QL2 are high-strength, fine-grain, quenched and tempered (Q+T) steel plates, conforming to EN 10028-6 standard, designed for welded pressure vessels and boilers, offering excellent mechanical properties and low-temperature toughness, with the 'P' indicating pressure vessel use, the number its minimum yield strength (355 MPa & 460 MPa), 'QL2' denoting superior low-temperature impact properties (Charpy V-notch), and '2' signifying enhanced weldability/toughness over 'QL1' grades.
Chemical Composition
|
P355QL2 Chemical Composition |
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|
Grade |
The Element Max (%) |
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|
C |
Si |
Mn |
P |
S |
N |
B |
|
|
P355QL2 |
0.16 |
0.4 |
1.5 |
0.020 |
0.010 |
0.015 |
0.005 |
|
Mo |
Cu |
Nb |
Ni |
Ti |
V |
Zr |
|
|
0.25 |
0.3 |
0.05 |
0.5 |
0.03 |
0.06 |
0.05 |
|
|
P460QL2 Chemical Composition |
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|
Grade |
The Element Max (%) |
||||||
|
C |
Si |
Mn |
P |
S |
N |
B |
|
|
P460QL2 |
0.18 |
0.50 |
1.70 |
0.020 |
0.010 |
0.015 |
0.005 |
|
Mo |
Cu |
Nb |
Ni |
Ti |
V |
Zr |
|
|
0.50 |
0.3 |
0.05 |
0.5 |
0.03 |
0.06 |
0.05 |
|
Mechanical Property
|
Grade |
P355QL2 Mechanical Property |
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|
Thickness |
Yield |
Tensile |
Elongation |
|
|
P355QL2 |
mm |
Min Mpa |
Mpa |
Min % |
|
6-50 |
355 |
490-630 |
22% |
|
|
50-100 |
335 |
490-630 |
22% |
|
|
100-150 |
315 |
450-590 |
22% |
|
|
Grade |
P460QL2 Mechanical Property |
|||
|
Thickness |
Yield |
Tensile |
Elongation |
|
|
P460QL2 |
mm |
Min Mpa |
Mpa |
Min % |
|
6-50 |
460 |
550-720 |
19% |
|
|
50-100 |
440 |
550-720 |
19% |
|
|
100-150 |
400 |
500-670 |
19% |
|
Key Characteristics & Differences:
Standard: Both fall under EN 10028-6 for weldable fine grain steels, quenched and tempered, used in demanding industrial applications.
Strength: P355QL2 offers a minimum yield strength of 355 MPa, while P460QL2 provides higher strength with a minimum yield of 460 MPa, making it suitable for higher pressure applications.
Temperature Performance: The "QL2" suffix signifies excellent low-temperature toughness (sub-zero impact testing) and improved weldability compared to QL1 grades, crucial for cryogenic or cold-climate use.
Applications: Common in high-pressure boilers, tanks, and reactors, particularly where welding is involved and good impact resistance at low temperatures is essential.
