Experimental investigation of the single screw extruder with grooved melting zone

Abstract

The barrel grooves of feeding zone were extended to the melting zone in a single screw extruder (SSE). A novel melting mechanism for SSE with grooved melting zone and anticompression screw was proposed, and a new hydraulic quick‐opening SSE platform was specifically designed and built to verify the model using materials of PP and HDPE. Comparative experiments were carried out for investigating melting behavior with various combinations of barrels and screws. For the ability of building reasonable pressure, the anticompression screw fits SSE with grooved melting zone. The solids in barrel grooves were melted quickly at the beginning of melting zone and kept melted state in the entire melting zone, which greatly improved the melting of solids in screw channel. Compared with conventional SSE, it was found that actual melting temperature was about 10°C higher in the case of SSE with grooved melting zone and anticompression screw. Although melting of polymer in the screw channel started at a later time, the melting length of SSE with grooved melting zone was greatly shortened by 50%, compared with that of traditional extruder. The melting efficiency and the throughout were also improved significantly. POLYM. ENG. SCI., 58:1555–1563, 2018. © 2017 Society of Plastics Engineers

Effect of processing conditions on the microstructure of microcellular PP/WF composites prepared by the continuous extrusion molding technology

“…Therefore, the screw speed was changed to adjust the melt pressure indirectly. As the screw speed increased, the melt conveying efficiency was also improved, which caused the more melts accumulated and compressed reciprocally in the die [21][22][23]. As a result, the melt pressure in the die essentially increased with the screw speed.…”