The following are the general reference values for the tensile strength, cold bending and welding performance of threaded steel:
Tensile strength:
The standard value of the tensile strength of HRB400 threaded steel should not be less than 400 MPa; the standard value of the tensile strength of HRB500 threaded steel should not be less than 500 MPa.
The standard value of the tensile strength of HRB400 threaded steel should not be less than 400 MPa; the standard value of the tensile strength of HRB500 threaded steel should not be less than 500 MPa.
Cold bending performance:
It is usually required that the threaded steel undergoes cold bending tests under the specified bending mandrel diameter and bending angle, and there shall be no cracks, fractures or delamination and other defects. The specific bending mandrel diameter and bending angle will vary depending on the grade and specification of the threaded steel.
It is usually required that the threaded steel undergoes cold bending tests under the specified bending mandrel diameter and bending angle, and there shall be no cracks, fractures or delamination and other defects. The specific bending mandrel diameter and bending angle will vary depending on the grade and specification of the threaded steel.
Welding performance:
The welded joints should meet the requirements in terms of strength, toughness and plasticity. The quality of the welded joints is generally tested through tensile tests, bending tests, etc. The tensile strength of the welded joint should not be lower than the lower limit of the tensile strength specified for the base metal.
The welded joints should meet the requirements in terms of strength, toughness and plasticity. The quality of the welded joints is generally tested through tensile tests, bending tests, etc. The tensile strength of the welded joint should not be lower than the lower limit of the tensile strength specified for the base metal.
It should be noted that the specific qualified values may vary due to different national standards, industry standards and engineering requirements. In practical applications, relevant standard specifications, such as “Steel for Reinforced Concrete – Part 2: Hot Rolled Ribbed Bars” (GB/T 1499.2-2018), etc., should be referred to determine the accurate and applicable qualified values.
For example, for HRB400 threaded steel with a diameter of 20mm, during the cold bending test, the bending mandrel diameter may be 4 times the diameter of the steel bar, and the bending angle is 180 degrees. In some specific projects, higher performance requirements for threaded steel may be imposed.
