Method for eliminating shear cracks of steel sections of sucker rods

The invention provides a method for eliminating shear cracks of steel sections of sucker rods. The method includes the steps: setting rolling starting temperature; rolling; controlling finishing; shearing the steel; stacking rod bundles. 20Cr2Mo steel is taken as an example, the rolling starting temperature of the steel with the diameter phi 19 is 1080-1120 DEG C, and the rolling starting temperature of the steel with the diameter phi 22-28 is 1070-1110 DEG C. The frame speed of finished steel with the diameter phi 19-28 is 7.5-8.0 meters per second, specified lengths are multiplied according to a multiple length, top cropping and back-end cropping quantities are added, and the length of the finished steel is 80-87 meters. The stepping cycle of a cold bed is 3.4 seconds, a step is reserved between an upper cold bed multiple length and the multiple length of the steel with the diameter phi 19-28, residence time is shortened, and the multiple length steel temperature is higher than or equal to 350 DEG C. After the multiple length contracts with cold, the upper limit deviation value is controlled to range from -10mm to +0mm. The gap value of shear blades is 0.05-0.18mm. The rod bundles are stacked and covered with canvases for slow cooling, and the cracks of the sections are avoided.