FIELD: process engineering.
SUBSTANCE: invention relates to extrusion into pellets of polymers of thermoplastic polyesters or copolyesters from polyester melt. Proposed method consists in feeding polyester melt into nozzles to make bunches thereof to be driven by stretching rolls into pelletiser. Note here that bunch stretching speed Vab is adjusted by stretching rolls. Bunches escape from nozzles at speed Vaus making at least 110 m/min. Note here that relationship Vaus/f (speed Vaus to nozzle outlet area f) is set to satisfy the condition Vaus/f≥30 m/(min×mm2) for bunches to be brought in contact with cooling fluid. Proposed device comprises nozzles with outlet to feed bunches by fed fluid. Besides said device comprises pelletiser and stretching rolls to feed bunches from nozzles into pelletiser. Note here that nozzle outlet diameter d or length l are set to make relation l/d satisfy the relation l/d≤1, preferably l/d≤0.7, more preferably l/d≤0.5, and more preferably l/d=0.3.
EFFECT: ruled out adhesion of pellets, lower costs, simplified process.
32 cl, 7 ex, 2 dwg
