This standard specifies the order contents; classification and code; section, dimension and permissible deviations; length and permissible deviation; shape; weight and permissible deviation; technical requirements and marking example of cold forming hollow sectional steel for general structure.
This standard is applicable to the circular, rectangular and square cold forming hollow sectional steel (hereafter referred to as "sectional steel") made of cold-rolled or hot-rolled steel sheet and strip by the continuous roller cold forming units, as well as the continuously hot-dip coated sectional steel, but not applicable to the sectional steel produced by methods such as drawing, stamping and bending and those made of galvanized steel plate and strip by cold forming and welding forming.
As for the sectional steel specified in this standard, high frequency resistance welding method is mainly adopted; argon arc welding or other welding methods may also be adopted.
2 Normative References
The following referenced document is indispensable for the application of this document. For dated reference, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 6725 General Requirements of Cold Forming Steel Sections
3 Order Contents
The order contract or order based on this standard shall include the following information:
a) Standard number;
b) Product name;
c) Designation;
d) Delivery weight;
e) Dimension and shape;
f) Special requirements.
4 Classification and Code
Sectional steel is classified into square, rectangular and circular shapes, and their codes are as follows:
