The granulation process is required for the production of profiles from single screw extruders. The ultimate goal of granulation is to achieve pre-plasticization of pvc plastics so that full plasticization can be achieved when the profiles are produced. In the granulation process, the purpose of plasticization is to promote the shearing, mixing, plasticizing and the like of the PVC by heating and shearing force to drive out the volatiles therein. The granulation can be carried out using a single screw extruder or a twin screw extruder, the former being less efficient than the latter. When granulating with single-screw extruder, temperature control: 100 °C to 120 °C at the front of the fuselage, 130 °C to 150 °C in the middle, 140 °C to 160 °C in the rear, 150 °C to 160 °C in the neck, 150 °C in the head 170 ° C. The screw speed is 10-16 r/min. When granulating with a twin-screw extruder, the temperature can be as low as 5 ° C to 10 ° C. Particle size: The size of the particles is required to be uniform, and the size of the shape is generally 3-4 mm. The size of the particles directly affects production efficiency. If the particles are too large, it is difficult to feed during molding, resulting in a decrease in yield. The shape of the particles is preferably spherical or tablet-shaped. One of the methods for evaluating the quality of granulation is to immerse the particles in an acetone solution at room temperature for 2 hours, and if the swelling ratio is less than 40% to 50%, the granulation plasticization is good. The color of the particles should be consistent. Aluminum Casting Auto Parts,Aluminum Auto Parts,Aluminum Spare Auto Parts,Heavy Truck Auto Parts NINGBO AIKEHAN METAL PRODUCT CO.,LTD , http://www.diecastingsupplier.com
/*kangxianyue 250*250 was created on 2017/3/29*/ var cpro_id = "u2939694";