The extruder is extruded through the fixed shape of the extruder under the action of the screw, and is cut by water cooling under the action of the tractor. It is mainly used in the continuous production of a large number of extruders with the same cross section, such as pipe rod and other materials, and can also be used in plastic modified granulation. The basic mechanism of extrusion is simple - a screw Rotate in the cylinder and push the plastic forward. The screw is actually an inclined plane or a slope that winds around the center layer. The aim is to increase pressure to overcome greater resistance. As far as an extruder is concerned, there are 3 kinds of resistance to be overcome: the friction force of the solid particle feed on the wall and the friction between the feed areas in the front of a few circles before the screw rotates, the adhesion of the melt on the wall of the cylinder, and the internal logistics resistance of the melt when it is pushed forward.
It is divided into single screw extruder and twin screw extruder. For many people who have not known the extruder, the operation of the extruder is very mysterious, and there are many already, or the people who are using the extruder, do not understand the correct operation specification of the extruder. Operators should pay attention to the use of extruders: the extruder operators should memorize the operating requirements and operation sequence of the instructions for extruders. Before driving, check the screw and nut of each connecting part on the equipment, whether the lubricating parts are added to the lubricating oil, and whether the quantity of oil in the tank is within the specified oil level. Check whether the hopper is clean, without any foreign body.
Check whether the raw materials meet the quality requirements; if the quality of the raw materials is qualified, feed them to the hopper and fill them up. Verify the structure of screw is in line with the production process requirements. After confirming that the cylinder is clean and no foreign matter is found, filter net, diffuser plate and molding die are installed. Adjust the temperature of the automatic control instrument on the set control box according to the requirements of the plasticizing process. The heating system is started, the cylinder and the mould are heated up. When the temperature is up to 1.5h, the heating temperature should be kept constant. The V belt wheel part of manual barring wheel should be flexible and easy to move without blockage. Start the lubricating oil pump and check whether the lubricating oil pipeline is smooth and whether the location of the lubricating oil supply is accurate.
After lubricating oil supply 3min, adjust the main motor speed knob to zero position, start the screw at low speed and turn the main motor to work. At the same time, the swing of the current meter pointer of the main motor should be observed. It should be within the specified load range. Note: the shorter the screw transit time is, the better the length should not exceed 3min, so as to avoid scratching the screw and barrel. Open the hopper feed gate, feed slowly and evenly. Start the cooling device. Open the cooling water supply system. Start the traction device. Check the plasticizing quality of the melt extruded from the die opening, and install the sizing sleeve when the melt is completely plasticized evenly. If the tube blanks extruded from the die die are inclined, the clearance between the die and the mandrel should be adjusted immediately. When adjusting, release the adjusting screws on the thin side of the billet wall and tighten the adjusting screws on the thick side of the billet until the billet runs in a straight line. Note: when the gap between the die and the mandrel is adjusted or the quality of the plasticization of the molten material is observed, the operator can not face the die opening to prevent the explosion of the scald operator.
After the extrusion regulation of the billet is normal, the tube blank is led into the sizing sleeve, the human tank is drawn into the traction machine, and the speed of adjusting the traction speed is appropriately matched with the extrusion speed of the tube blank from the die opening. Cut off the tube products and sample. The quality and size of the inspection products should conform to the quality requirements specified in the production. After checking the quality of the pipe products, the sound of the equipment is not abnormal, and the current load is normal, so that the working speed of the screw can be increased to the normal production speed. After the extrusion production turns to normal work, the operator should always pay attention to the following work: whether the motor load current of the driving motor is normal, whether it is in the rated range, or not in the rated range; the rotation of the working parts of each movement is abnormal; the temperature rise of each bearing position is normal, the highest temperature rise should not exceed 55 degrees C; the lubricating oil and the cooling can be cooled. Whether there is leakage in the water pipe and whether the working flow pressure is within the prescribed value. In case of a sudden blackout or abnormal accident in work, emergency shutdown should be made, and the speed adjustment knobs should be adjusted to zero.
It is divided into single screw extruder and twin screw extruder. For many people who have not known the extruder, the operation of the extruder is very mysterious, and there are many already, or the people who are using the extruder, do not understand the correct operation specification of the extruder. Operators should pay attention to the use of extruders: the extruder operators should memorize the operating requirements and operation sequence of the instructions for extruders. Before driving, check the screw and nut of each connecting part on the equipment, whether the lubricating parts are added to the lubricating oil, and whether the quantity of oil in the tank is within the specified oil level. Check whether the hopper is clean, without any foreign body.
Check whether the raw materials meet the quality requirements; if the quality of the raw materials is qualified, feed them to the hopper and fill them up. Verify the structure of screw is in line with the production process requirements. After confirming that the cylinder is clean and no foreign matter is found, filter net, diffuser plate and molding die are installed. Adjust the temperature of the automatic control instrument on the set control box according to the requirements of the plasticizing process. The heating system is started, the cylinder and the mould are heated up. When the temperature is up to 1.5h, the heating temperature should be kept constant. The V belt wheel part of manual barring wheel should be flexible and easy to move without blockage. Start the lubricating oil pump and check whether the lubricating oil pipeline is smooth and whether the location of the lubricating oil supply is accurate.
After lubricating oil supply 3min, adjust the main motor speed knob to zero position, start the screw at low speed and turn the main motor to work. At the same time, the swing of the current meter pointer of the main motor should be observed. It should be within the specified load range. Note: the shorter the screw transit time is, the better the length should not exceed 3min, so as to avoid scratching the screw and barrel. Open the hopper feed gate, feed slowly and evenly. Start the cooling device. Open the cooling water supply system. Start the traction device. Check the plasticizing quality of the melt extruded from the die opening, and install the sizing sleeve when the melt is completely plasticized evenly. If the tube blanks extruded from the die die are inclined, the clearance between the die and the mandrel should be adjusted immediately. When adjusting, release the adjusting screws on the thin side of the billet wall and tighten the adjusting screws on the thick side of the billet until the billet runs in a straight line. Note: when the gap between the die and the mandrel is adjusted or the quality of the plasticization of the molten material is observed, the operator can not face the die opening to prevent the explosion of the scald operator.
After the extrusion regulation of the billet is normal, the tube blank is led into the sizing sleeve, the human tank is drawn into the traction machine, and the speed of adjusting the traction speed is appropriately matched with the extrusion speed of the tube blank from the die opening. Cut off the tube products and sample. The quality and size of the inspection products should conform to the quality requirements specified in the production. After checking the quality of the pipe products, the sound of the equipment is not abnormal, and the current load is normal, so that the working speed of the screw can be increased to the normal production speed. After the extrusion production turns to normal work, the operator should always pay attention to the following work: whether the motor load current of the driving motor is normal, whether it is in the rated range, or not in the rated range; the rotation of the working parts of each movement is abnormal; the temperature rise of each bearing position is normal, the highest temperature rise should not exceed 55 degrees C; the lubricating oil and the cooling can be cooled. Whether there is leakage in the water pipe and whether the working flow pressure is within the prescribed value. In case of a sudden blackout or abnormal accident in work, emergency shutdown should be made, and the speed adjustment knobs should be adjusted to zero.
