The flat yarn making machine is adopted micro-processor control, frequency conversion governor and setting and displaying technical data may be fully digitized on the basis of absorbing international advanced techniques. The main parts use quality products. The line enlarges L/D ratio and adopts new type of separating screw and widens mixing smelt zone on the extruder screw pot which is specially processed using quality steel, fine plasticized effect, low energy consumption in relation to output. For the change filter system of the flat film stretching line, we apply advanced automatic belt change filter. The bake-board is changed into advanced hot drawing oven and principal technical index of the line reaches international advancing level.