S275JR square tubing is a common type of structural steel pipe with a square cross-section. Made from S275JR steel, it possesses specific mechanical properties and chemical composition, making it suitable for various structural supports and frame construction applications.
Material Characteristics
S275JR steel belongs to the non-alloy structural steel category. The "S" in its name represents structural steel, "275" indicates a minimum yield strength of 275 MPa, and "JR" signifies a certain impact toughness at room temperature. The chemical composition of S275JR square tubing mainly includes elements such as carbon, manganese, silicon, phosphorus, and sulfur. The carbon content is controlled at a low level to help maintain good weldability and formability. Manganese improves strength and toughness, silicon aids in deoxidation, and phosphorus and sulfur, as impurity elements, are limited to a low range to ensure stable material properties.
In terms of mechanical properties, S275JR square tubing has a minimum yield strength of 275 MPa and a tensile strength between 410 and 560 MPa. This type of steel pipe also possesses a certain elongation, typically exceeding 20%, enabling it to withstand a certain degree of deformation without breaking. Regarding impact toughness, S275JR material achieves an impact energy exceeding 27 Joules in a Charpy V-notch impact test at room temperature, indicating good impact resistance at room temperature.
Production Process
S275JR square tubes are typically produced using cold bending or hot rolling processes. Cold bending involves repeatedly rolling the steel strip into a square cross-section, then sealing the joints with high-frequency welding. This process produces square tubes with high dimensional accuracy and a smooth surface, suitable for applications with stringent dimensional requirements. Hot rolling involves heating the steel billet to a high temperature and then forming it into a square tube using a rolling mill. Hot-rolled square tubes typically have thicker walls, allowing them to withstand higher loads.
During production, quality control includes raw material inspection, forming process monitoring, welding quality inspection, and final product testing. Upon arrival at the factory, raw materials must be verified against material certificates to ensure the steel conforms to the S275JR standard. During the forming process, roller pressing parameters need to be adjusted to ensure accurate cross-sectional shape and dimensions. In the welding process, current and speed must be controlled to ensure strong welds. The final product requires dimensional measurement, surface inspection, and sampling for mechanical property testing to ensure each batch meets standard requirements.
Application Areas
S275JR square tubing is widely used in building structures, machinery support frames, warehouse racking, exhibition display frames, and other applications. In building structures, this square tubing is commonly used for beam and column supports, roof trusses, etc. Its square cross-section facilitates connection and installation, and effectively transfers loads. In the machinery field, S275JR square tubing can be used to manufacture equipment bases, guardrails, and other components; its stable performance ensures safe equipment operation.
Warehouse racking is another important application area for S275JR square tubing. Rack uprights and beams are typically made of square tubing; its uniform cross-sectional distribution ensures more even stress distribution when bearing the weight of goods, reducing the likelihood of localized deformation. The exhibition frame uses S275JR square tubing primarily because of its neat appearance, ease of painting, and ability to meet the needs of different exhibition designs.
S275JR Hollow Section facatory
