Preparation method of caterpillar polyester drawn yarn with good dyeing performance

The invention relates to a preparation method of a caterpillar polyester drawn yarn with good dyeing performance, which comprises the following steps of: extruding a polyester melt from a spinneret plate; the production method comprises the following steps: sequentially performing circular blowing cooling, primary oiling, primary pre-interlacing, a godet hook, a double-row reverse U-shaped porcelain piece, a GR1 godet, an HR2 hot roller, an HR3 hot roller, an HR4 hot roller, an HR5 hot roller, secondary oiling, secondary pre-interlacing, a GR6 godet, a main interlacing, a GR7 godet, and winding and forming to obtain a product. An air duct for circular air blowing is divided into an upper part and a lower part, the upper part is an area which is 10cm downwards from the top end of the air duct, the other part is the lower part, the air speed of cooling outlet air in the upper part of the air duct is 0.60-0.70 m/s, and the air speed of cooling outlet air in the lower part of the air duct is linearly and progress