Hot rolled state of delivery state of precision stainless steel pipe

The hot-rolled state of the stainless steel in the delivery state is no longer subjected to special heat treatment after hot rolling or forging, and it is delivered directly after cooling, which is called hot-rolled or hot forged state. The termination temperature of hot rolling (forging) is generally 800~ At 900°C, it is generally cooled naturally in the air afterwards, so the hot-rolled (forged) state is equivalent to normalizing treatment. The difference is that the end temperature of hot rolling (forging) is high or low, unlike normalizing, which has strict heating temperature control, so the steel structure and properties fluctuate more than normalizing. At present, many steel companies adopt controlled rolling. Due to the strict temperature control of the final rolling and forced cooling measures after the final rolling of the sanitary elbow, the grain size of the steel is refined and the delivered steel has higher comprehensive mechanical properties. . This is the reason why non-twist controlled cold and hot-rolled wire rod has better performance than ordinary hot-rolled wire rod. Steel delivered in hot-rolled (forged) state has a certain degree of corrosion resistance because the surface is covered with a layer of oxide scale. It is stored and transported. The requirements are not as strict as the steel delivered in the cold drawn (rolled) state. Large and medium-sized steel and medium-thick steel can be stored in the open yard or after being covered.