Common classification method of spiral steel pipe

There are two commonly used classification methods for spiral steel pipes: one is geometrically classified according to the cross-sectional shape of the transverse ribs and the spacing of the ribs. For example, the British standard (BS4449) divides the rebar into type I, Type II. This classification mainly reflects the grip performance of the rebar. Second, the performance classification (grade), such as our standard (G B1499), according to the strength level (yield point / tensile strength) will be divided into three grades of rebar; Japan Industrial Standard (JI SG3112), according to comprehensive performance The rebar is divided into five categories; the British standard (BS4461), also provides a number of grades of rebar performance test. In addition, according to the purpose of the classification of rebar, such as reinforced concrete is divided into ordinary reinforced concrete and reinforced concrete reinforced with heat treatment.