S355JR structural steel pipe is a type of structural steel widely used in construction and machinery manufacturing.
Grade Interpretation:
"S" represents structural steel;
"355" indicates the minimum yield strength of the steel is 355 MPa;
"JR" indicates the impact toughness grade and delivery condition of the steel. JR indicates that the impact test was conducted at room temperature and the steel is delivered in a hot-rolled condition.
Chemical Composition:
Its main chemical components include:
Carbon (C) ≤0.22%
Silicon (Si) ≤0.55%
Manganese (Mn) ≤1.60%
Phosphorus (P) ≤0.025%
Sulfur (S) ≤0.025%
Trace amounts of other alloying elements may be added to improve performance.
Mechanical Properties:
Yield strength ≥355 MPa
Tensile strength between 480 MPa and 620 MPa
Elongation ≥17%, exhibiting good plastic deformation capacity.
Manufacturing process: Hot rolling or normalizing is usually used. Hot rolling allows the steel to obtain the desired cross-sectional shape and size, while normalizing eliminates internal stress, improves microstructure and properties, and ensures that the steel has a uniform and dense microstructure, thereby improving its mechanical properties and weldability.
Application Areas and Market Demand
S355JR structural pipes have a wide range of applications, covering multiple industries including construction, machinery, shipbuilding, bridges, chemicals, petroleum, and power.
In the construction industry, S355JR square and rectangular tubes are commonly used in beams, columns, and floor slabs of high-rise buildings, factories, and bridges.
In the shipbuilding industry, this steel can be used to manufacture structural components such as decks, bulkheads, and trusses.
In the machinery manufacturing industry, S355JR structural pipes can be used to manufacture various mechanical parts and components.
In the petrochemical and power equipment manufacturing industries, S355JR hollow tubes also play an important role.
With the continuous development of the global economy and the ongoing advancement of infrastructure construction, the market demand for S355JR steel pipes is showing a continuous upward trend.
S355JR Steel Tube Factory
