Polyacrylonitrile filaments and fibers may be obtained without interruption by spinning the spinning solution into a hot-air spinning duct, washing, drawing, crimping, preparing, steaming, drying cooling and, optionally, cutting at a take-off rate kept at 150 to 400 m/minute and for a tow weight of from 10 to 100 g/m when(a) the washing process is carried out in several stages on the countercurrent principle and a vibrating duct is used for transporting the spun tow through the washing process,(b) drawing is carried out before and/or after washing in a steam atmosphere at 100.degree. to 120.degree. C.,(c) crimping is carried out in an aerodynamic crimping unit using a hot, gaseous medium under a pressure of from 5 to 16 bars and at a temperature in the range from 50.degree. to 210.degree. C.,(d) the preparation is continuously applied to the tow before, during or after crimping,(e) for steaming, the tow is transported through a steaming apparatus in folded form and in the absence of tension on a vibrating duct and, at the same time, treated with steam at 100.degree. to 120.degree. C.,(f) finally, the tow is dried in folded form on a belt dryer using hot air at 60.degree. to 180.degree. C., subsequently cooled with cold air to temperatures below 50.degree. C. and, optionally, delivered to a cutting machine.