Products Description
Understanding the Role of Low-Temperature Steel Grades
P275NL1 and P275NL2 are low-temperature pressure vessel steel grades under EN 10028-3, designed to maintain impact toughness at –40°C and –50°C respectively. These grades are essential for cold-region or cryogenic-related applications.
However, not every pressure vessel operates in such extreme conditions. In many projects, selecting a low-temperature grade may be unnecessary.
EN 10028-3 N is the room temperature quality, NH is for the elevated temperature quality, NL1 is for the low temperature quality and NL2 is for the special low temperature quality.
These steel grades are characterized by a minimum yield strength of 235 - 355 MPa and by good weldability. These grades are used above all for manufacturing boilers, pressure vessels and pipes transporting hot liquids. The user of these steel grades must make sure that his calculation, design and processing methods are appropriate for the material. The grades of this series offer good cold and hot-forming properties.
When P275N Is the Most Practical Choice
P275N steel plate should be chosen instead of P275NL1 or P275NL2 when:
- Operating temperature remains above freezing
- No low-temperature impact test is specified
- Equipment is installed in controlled industrial environments
- Project budget and material efficiency are important
In these situations, P275N provides sufficient safety and performance without the added cost associated with low-temperature testing and stricter production controls.
|
P275N Chemical Composition |
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|
Grade |
The Element Max (%) |
||||||
|
C |
Si |
Mn |
P |
S |
Al(min) |
N |
|
|
P275N |
0.18 |
0.40 |
0.5-1.40 |
0.030 |
0.025 |
|
0.02 |
|
Cr |
Cu |
Mo |
Nb |
Ni |
Ti |
V |
|
|
0.30 |
0.30 |
0.08 |
0.005 |
0.50 |
0.03 |
0.05 |
|
Carbon Equivalent: Ceq = 【C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15】%
|
Grade |
|
P275N Mechanical Property |
|||||
|
Thickness |
Yield |
Tensilmie |
Elongation |
Impact Energy(KV J) min |
|||
|
P275N |
mm |
Min Mpa |
Mpa |
Min % |
-20° |
0° |
+20° |
|
≤ 16 |
275 |
390-510 |
24 |
40 |
47 |
55 |
|
|
16> to ≤35 |
275 |
390-510 |
24 |
40 |
47 |
55 |
|
|
35> to ≤50 |
265 |
390-510 |
24 |
40 |
47 |
55 |
|
|
50> to ≤70 |
255 |
390-510 |
24 |
40 |
47 |
55 |
|
|
70> to ≤100 |
235 |
370-490 |
23 |
40 |
47 |
55 |
|
|
100> to ≤150 |
235 |
350-470 |
23 |
40 |
47 |
55 |
|
Cost and Supply Considerations
Low-temperature grades typically involve:
- Additional impact testing
- Stricter quality control
- Higher production and certification costs
For standard pressure vessel applications, specifying P275NL1 or P275NL2 may result in over-specification without delivering real technical benefits. P275N helps avoid unnecessary material expenses while still meeting design requirements.
Performance Comparison Overview
| Grade | Impact Test Requirement | Typical Application |
|---|---|---|
| P275N | Standard | Normal temperature pressure vessels |
| P275NL1 | –40°C | Cold-region pressure equipment |
| P275NL2 | –50°C | Extreme cold environments |
Engineering and Procurement Perspective
From both engineering and procurement viewpoints, P275N is often the most balanced solution. It simplifies sourcing, reduces lead time, and lowers overall project cost while maintaining compliance with pressure vessel standards.
P275N steel plate should be selected whenever low-temperature impact resistance is not a design requirement. It offers reliable performance, cost efficiency, and wide availability for standard pressure vessel projects.
GNEE STEEL assists customers in selecting the most suitable P275 grade, helping avoid unnecessary upgrades while ensuring safety and compliance.
👉 Contact us for technical advice and competitive pricing.
FAQ：
What is P275N steel plate?
P275N is a normalized pressure vessel steel grade under EN 10028-3, designed for moderate temperature service.
What does the "N" mean in P275N?
"N" indicates the steel is supplied in normalized condition, ensuring stable mechanical properties.
What is the yield strength of P275N?
Minimum yield strength is 275 MPa (depending on thickness).
Is P275N a hot rolled steel plate?
Yes, P275N is produced by hot rolling followed by normalizing heat treatment.
What are typical applications of P275N steel?
Pressure vessels, boilers, storage tanks, heat exchangers, and industrial vessels.
