Cable-setting-free soluble ball seat plugging device and fracturing string

The invention discloses a cable-setting-free soluble ball seat plugging device and a fracturing pipe column. The cable-setting-free soluble ball seat plugging device comprises n stages of fracturing sliding sleeves which are sequentially connected in series from bottom to top. Each fracturing sliding sleeve comprises an outer cylinder and a sliding sleeve inner cylinder, an inner and outer connecting channel is formed in the upper end of the outer cylinder, the sliding sleeve inner cylinder is connected in the outer cylinder in a sleeving manner, an annular clamping groove is formed in the inner wall of the sliding sleeve inner cylinder, and the widths of the clamping grooves in all stages of fracturing sliding sleeves are sequentially increased from top to bottom; during fracturing construction, the cable-setting-free soluble ball seat plugging device is arranged in the sliding sleeve inner barrel of the corresponding stage according to the fracturing stage number, the sliding sleeve of the corresponding sta