What's the difference between primary and two grade steel and three grade steel?
There are two kinds of commonly used classification methods of thread steel: one is to shape classification, according to different space shapes and transverse rib rib for classification or type, such as the British Standard (BS4449), the thread steel is divided into type I and type ii. This classification mainly reflects the tightening performance of the threaded steel.
There are two levels of steel rebar, three steel, four steel grade difference, no grade steel, there are a lot of customers to wire (round) mistakenly called a steel. At present, China is gradually out of grade two steel, four steel grade two steel grade HRB335, three grade steel grade HRB400, four grade of steel wire is HRB500, (Pan Yuan) new material grades are HPB195, HPB235, HPB300, old wire material grades corresponding is Q195, Q235.
The two is the performance of classification (class), for example, China's current implementation of standards, (G B1499.2-2007) for steel wire for 1499.1-2008), according to the strength (tensile strength yield point / steel) will be divided into 3 levels; the Japanese industrial standard (JI SG3112), according to the comprehensive performance of the steel branch for the 5 species; the British Standard (BS4461), also provides some level of performance test of thread steel. In addition, the thread steel can be classified according to the use, such as reinforced concrete, ordinary steel bars and reinforced concrete bars for heat treatment.
