Key Points for Actual Operation of an Extruder: Starting Up
After the temperature of the extruder is controlled, it can be started. Before starting, the bolts of the die head and the extruder flange should be tightened again to eliminate the difference in thermal deformation between the bolts and the die head. The sequence of tightening the die head bolts is to tighten them diagonally, and the force applied should be approximately the same. When tightening the flange nuts of the machine head, the bolts around should be evenly tight and loose; otherwise, material will escape.
(2) To start the machine, select and press the "Ready to Start" button, then press the "Start" button. After that, slowly turn the speed adjustment knob of the extruder screw. The extruder screw will start to run at a slow speed. Then gradually increase the speed while adding a small amount of material. When feeding materials, always pay attention to the changes in the indications of the server ammeter and various other indicators. The torque of the extruder screw must not exceed the blue mark (generally 65%-75% of the torque gauge). Before the plastic aluminum profiles are extruded, no one is allowed to stand directly in front of the die to avoid accidents caused by bolt breakage or the release of bubbles due to the wet and cold raw materials. After the plastic is extruded from the die opening of the die head, the extruded material needs to be cooled and the traction belt equipment and shaping die pulled down, and these devices should be started. Subsequently, based on the indicated values of the control instruments and the regulations for the extruded products, each part is adjusted accordingly to ensure that the entire extrusion operation is in a normal state. And fill up the material according to the demand. For the twin-screw extruder, a metering feeder is selected to feed the material at a uniform speed.
(3) When the material feed into the mold is uniform and the plasticization is good, the traction belt molding can be carried out. The assessment of plasticization level relies on work experience, generally determined by the appearance of the extruded material, that is, the surface gloss, absence of impurities, no foaming, scorched material, or discoloration. When the extruded material is thinned by hand to a certain level without burrs or cracking and has a certain degree of extensibility, it indicates that the material is well plasticized. If the plasticization is insufficient, the extruder screw speed, barrel, and die temperature can be adjusted appropriately until the product meets the requirements.
(4) During the extrusion production process, all process parameters should be checked regularly according to the processing procedure to ensure everything is normal, and the process record sheet should be properly filled out. The quality of the profiles should be inspected according to the product quality inspection standards, and if any problems are found, corrective measures should be taken immediately.
After the temperature of the extruder is controlled, it can be started. Before starting, the bolts of the die head and the extruder flange should be tightened again to eliminate the difference in thermal deformation between the bolts and the die head. The sequence of tightening the die head bolts is to tighten them diagonally, and the force applied should be approximately the same. When tightening the flange nuts of the machine head, the bolts around should be evenly tight and loose; otherwise, material will escape.
(2) To start the machine, select and press the "Ready to Start" button, then press the "Start" button. After that, slowly turn the speed adjustment knob of the extruder screw. The extruder screw will start to run at a slow speed. Then gradually increase the speed while adding a small amount of material. When feeding materials, always pay attention to the changes in the indications of the server ammeter and various other indicators. The torque of the extruder screw must not exceed the blue mark (generally 65%-75% of the torque gauge). Before the plastic aluminum profiles are extruded, no one is allowed to stand directly in front of the die to avoid accidents caused by bolt breakage or the release of bubbles due to the wet and cold raw materials. After the plastic is extruded from the die opening of the die head, the extruded material needs to be cooled and the traction belt equipment and shaping die pulled down, and these devices should be started. Subsequently, based on the indicated values of the control instruments and the regulations for the extruded products, each part is adjusted accordingly to ensure that the entire extrusion operation is in a normal state. And fill up the material according to the demand. For the twin-screw extruder, a metering feeder is selected to feed the material at a uniform speed.
(3) When the material feed into the mold is uniform and the plasticization is good, the traction belt molding can be carried out. The assessment of plasticization level relies on work experience, generally determined by the appearance of the extruded material, that is, the surface gloss, absence of impurities, no foaming, scorched material, or discoloration. When the extruded material is thinned by hand to a certain level without burrs or cracking and has a certain degree of extensibility, it indicates that the material is well plasticized. If the plasticization is insufficient, the extruder screw speed, barrel, and die temperature can be adjusted appropriately until the product meets the requirements.
(4) During the extrusion production process, all process parameters should be checked regularly according to the processing procedure to ensure everything is normal, and the process record sheet should be properly filled out. The quality of the profiles should be inspected according to the product quality inspection standards, and if any problems are found, corrective measures should be taken immediately.