International standards for rhs steel

International standards for rhs steel

RHS steel is an abbreviation for rectangular tubes, which refers to standard sized steel tubes and pipes used for structural purposes. It is available in a range of sizes, with thicknesses typically ranging from 1.0mm to 6.0mm. It is usually made from hot rolled steel sheet, which is then cold-formed into a rectangular section. This type of steel is suitable for a variety of applications including bridges, building frames, fencing, and roofing, amongst others. 

The primary international standards for RHS steel are set by the International Organization for Standardization (ISO). ISO 898-1 is a primary document that specifies requirements for mechanical properties and test methods for determining mechanical parameters of steel such as yield strength, tensile strength, and hardness. There are also other relevant standards such as ISO 3573 which specifies additional requirements for steel grades and types, and ISO 4998 which specifies additional requirements for chemical properties including chemical composition and surface characteristics. Additionally, there are national standards in various countries that may further specify requirements for products within their jurisdiction. 

In addition to international and national standards, there are also industry standards that manufacturers adhere to in order to ensure the quality and safety of their RHS steel. For example, the American Society for Testing and Materials (ASTM) and the British International Standards (BS) are just two of many industry standards that relate to RHS steel.

Mechanical Properties of RHS Steel

The mechanical properties of RHS steel are determined by the ISO 898-1 standard. This standard specifies requirements for yield strength, tensile strength, and hardness. Yield strength is the point at which the material begins to deform without any additional force applied. Tensile strength is the point where the material will break when subjected to a given load. And finally, hardness is the resistance of the material to wear and tear. 

The requirements for minimum yield strength in RHS steel vary depending on the type of steel and the size of the section. For example, for Grade A36 steel with a section size of 2 x 2 inches, the minimum yield strength is 36 ksi (kilopounds per square inch). For the same grade of steel, the minimum tensile strength requirement is 58 ksi. The hardness requirements vary depending on the thickness of the section, with a minimum hardness value of 245 BHN (Brinell Hardness Number).

Chemical Properties of RHS Steel

The chemical properties of RHS steel are measured in accordance with the ISO 4998 standard. This standard specifies requirements for chemical composition and surface characteristics, such as cleanliness, phosphorus and sulfur content, and impurities. The chemical composition of RHS steel typically includes elements such as carbon, manganese, phosphorus, sulfur, silicon, and chromium. 

The phosphorus and sulfur content must be kept to a minimum in order to increase ductility and impact resistance. As a result, the phosphorus and sulfur content must be below 0.045% and 0.050%, respectively. The maximum allowable levels of impurities such as lead and copper are also specified, generally ranging from 0.30% to 0.50%. 

In conclusion, RHS steel is a hollow structural section used in construction, and it is subject to a wide range of international, national, and industry standards which ensure the quality and safety of the product. These standards specify requirements for both mechanical properties, such as yield strength and tensile strength, as well as chemical properties, such as chemical composition and surface characteristics. Together, these standards ensure that RHS steel will meet all requirements for the intended application.