SCREWS FOR EXTRUSION OF PLASTICS

摘要

FIELD: process engineering.SUBSTANCE: invention relates to screws of multishaft extruders and to extrusion of plastics. Efficient operation is ensured by screws incorporated with multishaft extruders with two screw shafts running in one direction to clean each other by scraping wherein sum of ridge angles of two screws is larger than or equals 0 and smaller than 2*?-8*arccos(0.5*a/ra). Amount of ridge areas of two screws exceeds 4. Note here that every screw of said pair has two areas of screw profile consisting in every case of side area and groove area whereat the sum of lateral angle and groove angle exceeds ?/2.EFFECT: higher efficiency at higher pressure and minimised thermal load at extruded product.14 cl, 39 dwg, 2 ex