Controlled rolling and controlled cooling production method for green small-specification HRB500E reinforcing steel bar

The invention discloses a controlled rolling and controlled cooling production method for a green small-specification HRB500E reinforcing steel bar. The method comprises the working procedures of heating, rolling and cooling; in the heating process, the soaking temperature is 1090-1150 DEG C; the initial rolling temperature of the rolling procedure is 970-1030 DEG C, and the finish rolling temperature of the rolling procedure is 900-980 DEG C; the temperature on a cooling bed in the cooling process is 900-980 DEG C; when the initial rolling temperature is 970-1030 DEG C, the rolled blank is continuously rolled into an intermediate product, then water cooling is conducted, the finish rolling temperature is controlled to be 900-980 DEG C, then water cooling is conducted, and the cooling bed feeding temperature is controlled to be 900-980 DEG C; the microstructure of the hot-rolled ribbed steel bar is mainly ferrite and pearlite, a hardening layer does not exist, the yield strength is 520 Mpa or above, the yield