In-step boring structure of guide vane shaft holes of both inner and outer gate barrels of through-flow turbine

The utility model provides an in-step boring structure of guide vane shaft holes of both inner and outer gate barrels of a through-flow turbine. The in-step boring structure comprises an inner gate barrel, an outer gate barrel and an in-step boring special machine, wherein the inner gate barrel is installed on a rotary disk through an universal bracket; the in-step boring special machine is arranged between the inner gate barrel and the outer gate barrel and is installed on an adjustment base; and the outer gate barrel and the inner gate barrel are coaxially arranged through a roller jack and a regulating positioning rod; positioning channel steel is connected between the inner gate barrel and the outer gate barrel; the flange face of the outer gate barrel is provided with a plurality of fixed support parts; one fixed support is arranged in the position corresponding to the in-step boring special machine; and the fixed support parts are provided with positioning pads for tightly pressing the outer gate barrel