1. Comparison of mechanical properties
The minimum yield strength of API 5L Grade B pipe is about 241MPa, the tensile strength is around 414MPa, and the elongation is over 30%. Its strength is moderate and its ductility is good. This makes it suitable for low-pressure and small deformation demand scenarios.
The minimum yield strength of API 5L X70 pipe is 483MPa, the tensile strength is over 570MPa, and the toughness is excellent. It can withstand the strong impact and complex external forces of high-pressure oil and gas. Its high strength can resist internal pressure and external load, and its high toughness can prevent fracture failure.
2. Differences in manufacturing process
API 5L Grade B is mostly manufactured by hot rolling and normalizing process. It is made of common carbon steel, contains carbon, manganese and other elements, has less alloy components, conventional process, low equipment and technical requirements, and low cost.
API 5L X70 is based on high-strength, low-alloy steel, containing niobium, vanadium, titanium and other alloy elements. Use thermomechanical controlled processing or quenching and tempering processes to strictly control the heating, deformation and cooling links and optimize the microstructure of steel. It requires high-end equipment and fine control, and the cost is relatively high.
3. Different application scenarios
API 5L Grade B is often used in places with low pressure and load, such as urban gas distribution network branches, small oil field gathering and transmission lines, etc., which can meet the needs of low-pressure and short-distance transportation and are cost-effective.
API 5L X70 shines in high-pressure, long-distance, and harsh environment transportation. For example, long-distance oil and gas trunk lines can efficiently transport oil and gas over long distances; deep-water offshore facilities can withstand high hydrostatic pressure and harsh sea conditions; polar and seismic areas can withstand extreme conditions to ensure stable transportation of oil and gas.
API 5L X70 spiral pipe Chemical Composition
| X70 PSL1 | X70 PSL2 | |||||||
| Grade | C (Max.) | Mn (Max.) | P (Max.) | S (Max.) | C (Max.) | Mn (Max.) | P (Max.) | S (Max.) |
| X70 | 0.26 | 1.65 | 0.03 | 0.03 | 0.22 | 1.85 | 0.025 | 0.015 |
API 5L X70 carbon steel spiral pipe Mechanical Properties
| Pipe Grade | Tensile Properties - X70 Pipe Body of SMLS and Welded Pipes PSL 1 | Seam of X70 Welded Pipe | ||
| Yield Strength a | Tensile Strength a | Elongation | Tensile Strength b | |
| Rt0,5 PSI Min | Rm PSI Min | (in 2in Af % min) | Rm PSI Min | |
| X70 | 70,300 | 82,700 | c | 82,700 |
API 5L Grade B pipe Chemical Composition
|
Grade |
Chemical Composition |
|||||||
|
API 5L Grade B Pipe |
C |
Si |
Mn |
P |
S |
V |
Nb |
Ti |
|
0.16 |
0.45 |
1.65 |
0.020 |
0.010 |
0.07 |
0.05 |
0.04 |
|
Mechanical Properties of API 5L Class B Pipes
|
Grade |
Permissible yield point ratio |
Yield Strength MPa(min) |
Tensile Strength MPa |
Elongation % (min) |
|
API 5l Grade B Pipe |
≤ 0.85 |
290 |
420 - 540 |
23 |
API 5L PSL1 X70 Seamless Pipe
