An API 5L Gr. B LSAW steel pipe is a large-diameter, welded pipe manufactured to the American Petroleum Institute (API) 5L standard for Grade B steel, using the longitudinal submerged arc welding (LSAW) process, and is suitable for oil, gas, water, and other fluid transportation systems. This pipe type features a single weld seam created by a long submerged arc welding process, is available in standard quality (PSL1) and higher-specification versions (PSL2) with additional testing, and offers excellent strength for high-pressure applications.
Key Characteristics
Standard: American Petroleum Institute (API) 5L, Grade B
Manufacturing Process: Longitudinal Submerged Arc Welding (LSAW)
Product Specification Level (PSL): Available in both PSL1 (standard) and PSL2 (enhanced testing and requirements)
Material: Carbon steel with specific chemical composition and mechanical properties for Grade B
Application: Primarily used in pipeline transportation systems for oil, natural gas, and water
Benefits and Features
High Strength: Possesses a minimum yield strength of 245 MPa (35,500 psi)
Corrosion Resistance: Can be coated with various materials like FBE, 3PE, or black paint for added protection
Large Diameters: LSAW welding is suited for the production of large-diameter pipes
Workability: The material has excellent workability and can be elongated significantly
PSL Levels Explained
PSL1: A standard quality pipe with basic chemical and mechanical requirements.
PSL2: A higher specification requiring more stringent chemical composition, mechanical properties, and testing, including fine-grain practices for the steel.
Equivalent Standards
API 5L Grade B is often referenced by ISO 3183.
It is considered equivalent in many aspects to American Society for Testing and Materials (ASTM) A106 Grade B and ASTM A53 Grade B.
Standard
Tolerance of Outside Diameter and Wall Thickness of LSAW Steel Pipe
|
Types |
Standard |
|||||
|
SY/T5040-2000 |
SY/T5037-2000 |
SY/T9711.1-1977 |
ASTM A252 |
AWWA C200-97 |
API 5L PSL1 |
|
|
Tube end OD deviation |
±0.5%D |
±0.5%D |
-0.79mm～+2.38mm |
<±0.1%T |
<±0.1%T |
±1.6mm |
|
Wall thickness |
±10.0%T |
D<508mm, ±12.5%T |
-8%T～+19.5%T |
<-12.5%T |
-8%T～+19.5%T |
5.0mm |
|
D>508mm, ±10.0%T |
T≥15.0mm, ±1.5mm |
|||||
Chemical Composition and Mechanical Properties of LSAW Steel Pipe
|
Standard |
Grade |
Chemical Composition(max)% |
Mechanical Properties(min) |
|||||
|
C |
Mn |
Si |
S |
P |
Yield Strength(Mpa) |
Tensile Strength(Mpa) |
||
|
GB/T700-2006 |
A |
0.22 |
1.4 |
0.35 |
0.050 |
0.045 |
235 |
370 |
|
B |
0.2 |
1.4 |
0.35 |
0.045 |
0.045 |
235 |
370 |
|
|
C |
0.17 |
1.4 |
0.35 |
0.040 |
0.040 |
235 |
370 |
|
|
D |
0.17 |
1.4 |
0.35 |
0.035 |
0.035 |
235 |
370 |
|
|
GB/T1591-2009 |
A |
0.2 |
1.7 |
0.5 |
0.035 |
0.035 |
345 |
470 |
|
B |
0.2 |
1.7 |
0.5 |
0.030 |
0.030 |
345 |
470 |
|
|
C |
0.2 |
1.7 |
0.5 |
0.030 |
0.030 |
345 |
470 |
|
|
BS EN10025 |
S235JR |
0.17 |
1.4 |
- |
0.035 |
0.035 |
235 |
360 |
|
S275JR |
0.21 |
1.5 |
- |
0.035 |
0.035 |
275 |
410 |
|
|
S355JR |
0.24 |
1.6 |
- |
0.035 |
0.035 |
355 |
470 |
|
|
DIN 17100 |
ST37-2 |
0.2 |
- |
- |
0.050 |
0.050 |
225 |
340 |
|
ST44-2 |
0.21 |
- |
- |
0.050 |
0.050 |
265 |
410 |
|
|
ST52-3 |
0.2 |
1.6 |
0.55 |
0.040 |
0.040 |
345 |
490 |
|
|
JIS G3101 |
SS400 |
- |
- |
- |
0.050 |
0.050 |
235 |
400 |
|
SS490 |
- |
- |
- |
0.050 |
0.050 |
275 |
490 |
|
|
API 5L PSL1 |
A |
0.22 |
0.9 |
- |
0.03 |
0.03 |
210 |
335 |
|
B |
0.26 |
1.2 |
- |
0.03 |
0.03 |
245 |
415 |
|
|
X42 |
0.26 |
1.3 |
- |
0.03 |
0.03 |
290 |
415 |
|
|
X46 |
0.26 |
1.4 |
- |
0.03 |
0.03 |
320 |
435 |
|
|
X52 |
0.26 |
1.4 |
- |
0.03 |
0.03 |
360 |
460 |
|
|
X56 |
0.26 |
1.1 |
- |
0.03 |
0.03 |
390 |
490 |
|
|
X60 |
0.26 |
1.4 |
- |
0.03 |
0.03 |
415 |
520 |
|
|
X65 |
0.26 |
1.45 |
- |
0.03 |
0.03 |
450 |
535 |
|
|
X70 |
0.26 |
1.65 |
- |
0.03 |
0.03 |
585 |
570 |
|
