Q355B seamless steel pipes are high-quality low-alloy structural steel tubes widely used in hydraulic systems, pipelines, construction, and oil & gas applications. Manufactured according to multiple international standards, these pipes ensure excellent mechanical properties, dimensional accuracy, and surface quality.
Material Type: Low-alloy steel (Q355B), 10#–45#, 20MnG, 25MnG, 15CrMoG, 35CrMo, 16Mn, and other grades
Manufacturing Technique: Hot rolled
Surface Treatment: Oil painting
Pipe Type: Thick wall seamless steel pipe
Certifications: API5L, ISO 9001:2008, SGS, BV, CCIC, CE (EN10204-3.1)
Specifications
| Parameter | Details |
|---|---|
| Outer Diameter | 21–1030 mm |
| Wall Thickness | 6–60 mm |
| Length | 5.8–12 m (customizable) |
| Section Shape | Round |
| Delivery Condition | Hot rolled, annealed, normalized, quenched & tempered |
| Surface | Oil painted / Varnished |
| End Type | Beveled, plain, or as required |
| Weight per Unit | 850 kg |
| Export Packaging | Bundled with plastic caps, markings per customer request |
| Lead Time | 15–30 days after full payment |
Standards and Grades
Q355B seamless pipes comply with:
ASTM / BS / DIN / ANSI standards including:
ASTM A106, A213, A312, A333, A335 series
BS 3059-2
DIN 17175, DIN 2448, DIN EN 10208-1, DIN EN 10217-1
ANSI B36.10M-2004, ASTM A420 WPL6 alloy steel
Applicable Grades: 10#–45#, A53–A369, Cr-Mo alloys, Q195–Q345, 45#, A333, A335 P1/P5/P9/P11/P12/P23, 10CrMo910, 12Cr2Mo
Mechanical & Chemical Testing
All pipes undergo comprehensive testing to ensure high quality and reliability:
Chemical Composition Analysis
Mechanical Properties Testing: Tensile strength, yield strength, elongation, hardness
Technological Tests: Flattening, flaring, bending, hydraulic pressure
Surface Quality Inspection
Eddy Current Examination
Visual Inspection
Applications
Low and medium pressure fluid pipelines
Casing pipes
Low and medium pressure boiler seamless steel pipes
High pressure boiler seamless steel pipes
Carbon seamless steel pipes for shipbuilding
High pressure chemical fertilizer equipment
Petroleum and natural gas pipelines
Heat exchangers
Diesel engines
Construction, chemical, environmental, and industrial equipment
Advantages of Q355B Pipes
Excellent mechanical properties and high yield strength (≥ 355 MPa)
Superior weldability and cold bending performance
Good toughness and ductility for structural applications
High corrosion resistance with surface coatings
Fully compliant with international quality and safety standards
Available in custom sizes and packaging options
