the yarn moving devices are effective when the oil content is on the order of 0 5 fig2 a to 2c are a sectional view a fragmentary side view and a general side view respectively of a cooling plate as shown in fig2 c two openings 25 are formed at two positions of the guide groove 20 of a cooling plate 9 and two yarn moving devices 29 are disposed in connection with the openings 25 respectively as shown in fig2 a and 2b each yarn moving device 29 comprises a reciprocating bar 28 driven for reciprocation by a driving device 30 a bracket 27 attached to the reciprocating bar 28 and a yarn guide 26 having a portion forming a u shaped guide groove and a funnel like portion disposed at the middle of the opening 25 and attached to the bracket 27 the yarn guides 26 of a plurality of drawing false twisting units are moved by the reciprocating bar 28 the yarn moving device 29 moves the yarn y regularly along the curved face of the yarn guide groove 20 in the cross sectional direction thereof as shown in fig1 the yarn moving devices 29 are disposed at an appropriate interval as shown in fig2 c so that the yarn y can be moved laterally at the middle point.