The structure of the pelleting part in the extrusion granulator is the main device in the auxiliary machine of the extrusion pelleting equipment.The pelletizing auxiliary machine can be divided into hot cutting and cooling parts according to its different working modes and functions,and hot cutting can be divided into dry cutting,water ring cutting and underwater cutting.Their specific working modes and application characteristics are as follows.
(1).The production method of dry cutting and dry pelletizing refers to that the strip material is immediately cut into granules with uniform length by the rotating blade after being extruded from the extruder,and then the granules are sent to the cooling and screening device by the fan through the pipeline.This pelletizing method is suitable for mixing and pelletizing of polyethylene materials.
(2).The production method of water ring cutting and water ring pelletizing refers to that the strip particles extruded by the extruder are immediately cut by the roating blade and thrown to the high-speed rotating water ring attached to the inner wall of the pelletizing cover,and than the water flow takes the particles to the water separator for dehydration,and after drying,they are sent to the material cooling device for cooling,which is the finished product.This production method is suitable for polyolefin mixing and pelletizing.
(3).The production method of underwater pelletizing refers to that the strips extruded by the extruder immediately enter the water for cooling,and then cut into granules,which are then sent to the centrifugal dryer by circulating water for dehydration and drying.This granulation method is more suitable for twin-screw extruding and mixing raw material granulation,and is used for large batch production.
(4).Cold pelletizing Cold pelletizing refers to the mixing and plasticizing of materials by the extruder,forming sheet materials from the molding die in front of the barrel,falling into the water tank for cooling and then coiling,and then pelletizing with a dedicated pelletizing.This extrusion pelletizing production method is suitable for mixing and pelletizing raw materials of polyethylene,polypropylene,ABS and polyethylene terephthalate.
