Textured yarn instability is affected by the interactions of overfeed with
texturing speed and of air pressure with texturing speed. With increased ov
erfeed and texturing speed, yam instability increases. Changes in instabili
ty are quite extensive when textured yarn is produced with higher overfeed
coupled with higher texturing speed. With increased air pressure, yarn inst
ability decreases at lower texturing speeds but increases at higher texturi
ng speeds.