BH is welded to H just, and RH is hot rolled H steel.
Section steel is a strip steel with definite section shape and size. It is one of the four big kinds of steel (plate, tube, mould, wire). According to the section shape, the section steel is divided into simple section steel and complex section steel (deformed steel). The former refers to the steel, round steel, flat steel, angle steel, six angle steel; the latter refers to the I-beam, channel steel, steel, steel, steel frame bending etc..
In accordance with the different smelting quality of steel, steel is divided into ordinary steel and high quality steel. According to the current catalogue of metal products, ordinary steel can be divided into large section steel, medium section steel and small section steel. The section steel can be divided into I-beam, channel steel, angle steel, round steel and so on according to its sectional shape.
