This article introduces a kind of structure for the bottom of the fan-shaped block of the tire blank in a two-drum light truck tire building machine, featuring a slight angle. This structure is applied to the 16″ all-steel radial tire product. The purpose of this structure is to improve a series of defects in the bead area of the original fan-shaped block, such as bead bubbles, bead under-fill, and bead edge protrusion (bead width). The results show that after changing the fan-shaped block from a seamless to a seamless design, by deepening the depth of the fan-shaped block and increasing the angle at its bottom, the angle of the fan-shaped block is brought closer to the bead angle, thus achieving better compatibility with the steel bead. This improves the squeezing force of the fan-shaped block on the inner side of the tire blank after lifting, solving the problem of edge warping on the inner side of the tire blank, while ensuring the consistency of the tire bead shape with the contour of the bead mold.