S235JR Rectangular pipe is a square or rectangular hollow section made from S235JR grade steel, which is a non-alloy structural steel defined by the European standard EN 10025-2 . The name "S235JR" breakdown: "S" stands for structural steel, "235" indicates a minimum yield strength of 235 MPa, and "JR" denotes that it can absorb at least 27 joules of impact energy at 0°C . This material is renowned for its excellent weldability, workability, and cost-effectiveness, making it a popular choice for various structural applications .

S235JR steel has a carefully controlled chemical composition to ensure its mechanical properties and processability.

Manufacturing and Standards

S235JR rectangular pipes are typically manufactured through a welding process (such as resistance welding) from hot-rolled steel strips or plates . They conform to European standards like EN 10219-1 . These pipes are usually supplied in the as-rolled condition, and their production process is controlled to ensure consistent dimensional accuracy and surface quality .

Standard sizes for rectangular pipes are diverse. Common widths and heights range from around 20mm to over 400mm, with thicknesses from about 2mm to 25mm . They are often available in standard lengths of 6m, 9m, or 12m .

Key Features and Advantages

S235JR rectangular pipes offer several distinct advantages:

Excellent Weldability and Formability: The low carbon content makes them suitable for various welding methods (e.g., arc welding, gas shielded welding) without preheating in most cases. They also handle cutting, drilling, and cold bending well .

Good Strength-to-Weight Ratio: The hollow rectangular section provides high load-bearing capacity and torsional stiffness while being lightweight, contributing to material efficiency .

Cost-Effective: As a widely produced grade, it offers a good balance of performance and affordability .

Dimensional Accuracy and Surface Quality: These pipes are known for their smooth surfaces, precise dimensions, and ease of connection and installation .

Recyclability: Like most steels, it is 100% recyclable .

Application Fields

S235JR rectangular pipes are versatile and used in numerous sectors :

Construction and Infrastructure: Building frames, roofs, support structures, bridges, transmission towers, and staircases.

Mechanical Manufacturing and Equipment: Equipment frames, machine guards, conveyor system supports, and various structural components for agricultural machinery.

Automotive and Transportation: Used in vehicle chassis frames and internal structures for ships.

Other Industrial Applications: Storage racks, agricultural greenhouse structures, and general-purpose containers.