API 5L GR.B Seamless Steel Pipe
API 5L Grade B Seamless Steel Pipe is a high-strength, carbon steel pipe manufactured according to the American Petroleum Institute (API) 5L specification , which is globally recognized for pipelines used in the oil and gas, petrochemical,...
API 5L Grade B Seamless Steel Pipe is a high-strength, carbon steel pipe manufactured according to the American Petroleum Institute (API) 5L specification, which is globally recognized for pipelines used in the oil and gas, petrochemical, and energy sectors. It is engineered for the transportation of oil, gas, water, and other fluids in both onshore and offshore applications, making it a widely used product in the construction of transmission pipelines, gathering lines, and structural piping systems.
As a Grade B steel pipe, this product offers a balanced combination of strength, ductility, weldability, and durability, making it suitable for moderate-pressure applications and structural use in demanding environments. The seamless construction enhances its integrity and resistance to internal and external pressure, as there are no welded joints that could weaken the pipe structure.
Material Composition and Manufacturing
API 5L GR.B seamless pipes are produced from high-quality carbon steel, typically containing elements such as carbon, manganese, phosphorus, and sulfur, with strict control over chemical composition to meet the API 5L standard. The seamless pipes are made using hot-rolled or cold-drawn techniques, followed by heat treatment (normalizing, stress relieving, or quenching and tempering, as needed) to ensure uniform mechanical properties throughout the length of the pipe.
The seamless process ensures:
No weld seam – eliminating weak points
Smooth internal surface – reducing friction and improving flow efficiency
High pressure resistance – suitable for long-distance, high-volume pipelines
Mechanical and Physical Properties
Tensile Strength: ≥ 415 MPa (60,200 psi)
Yield Strength: ≥ 245 MPa (35,500 psi)
Good impact resistance, even in moderate sub-zero temperatures
Excellent weldability using standard welding techniques
These properties make API 5L Grade B Seamless Steel Pipe a trusted material for high-stress, high-load applications in challenging field conditions.
Key Features
Seamless Design: Uniform structure with superior strength and pressure containment
Wide Range of Sizes: Outer diameters typically range from 1/2" to 36", with wall thicknesses from SCH10 to XXS or customized
Length Options: Single random length (5-7m), double random length (11-13m), or custom-cut lengths
End Types: Plain End (PE), Beveled End (BE), or Threaded End (TE)
Surface Coatings: Available with black painting, anti-corrosion oil, 3PE/3LPE coating, or galvanized finish
Dimensional Standards: Conforms to API 5L, ASME B36.10M, or other international specifications
Typical Applications
Oil & Gas Transmission Lines
Water Distribution and Supply Systems
Structural Steel Projects
Offshore and Subsea Installations
Petrochemical and Refinery Piping Systems
Boiler and Heat Exchanger Tubing
Heavy Equipment Manufacturing
Whether it’s laid across rugged terrain or buried underground in corrosive soil conditions, API 5L Grade B seamless pipe performs with strength, safety, and longevity.
Testing & Certification
Every pipe undergoes strict quality control and testing, including:
Hydrostatic pressure testing
Ultrasonic and Eddy current testing
Visual and dimensional inspection
Chemical and mechanical analysis
Pipes are certified with:
API 5L monogram license
ISO 9001, ISO 14001, ISO 45001
Third-party inspection reports (SGS, BV, Lloyd’s, TUV) available upon request
Why Choose API 5L GR.B Seamless Steel Pipe?
Choosing API 5L Grade B seamless steel pipe means investing in a durable, high-performance solution that delivers consistent results in high-pressure and corrosive service conditions. It is a versatile and economical choice for industries that demand both structural integrity and long service life.
