Today, Yankang will share with you the debugging and maintenance of the plasticizing system of the blow molding machine.
Debugging of plasticizing system
1) the heater of the plasticizing system must be tightened uniformly. The heater should closely and evenly adhere to the heating surface. Aiming at the mica heater, the rubber hammer should be used to gently beat the mica heater while fastening to ensure close fitting, which is conducive to uniform heating and prolong the service life of the heater.
2) The thermocouple probe must have sufficient spring preload to ensure accurate temperature measurement.
3The compression bolt of the die head of the storage cylinder is usually not suitable for complete tightening. It can be pressed gently to leave room for thermal expansion and cold shrinkage of the cylinder; The axis of the barrel should be straight and not bent.
4) Before heating, the cooling water of the barrel must be opened, and the cooling water of the die should be prevented to block the blockage of the barrel to prevent the cylinder seal on the gearbox and the die from aging and oil leakage.
5) The magnetic frame needs to be placed in the hopper to prevent iron filings from entering the screw, causing damage to the screw and die parts or blockage of the die flow path.
6) When the cold machine is started, it is generally recommended to reduce the extrusion speed. After the tube blank is normally extruded from the die, the speed is gradually increased.
7) Before the tube blank is normally extruded from the die, the person should not stand in front of the die and under the die; when the storage tank machine is in the first 3 shots, the personnel should be away from the die and manually shoot. The pressure is usually not too large (generally not more than 5 MPa).
8) The automatic injection pressure of the storage tank machine is usually not too large, and the actual time of the automatic shot is usually more than 5 seconds. The too-fast speed easily leads to inaccurate wall thickness tracking and melt fracture.
9)For machines equipped with a wall thickness control system, the wall thickness controller must be activated and manually operated once, and then the extrusion material is started to prevent the parts from being completely closed and the parts are damaged.
Maintenance of the plasticizing system
1) During the operation of the belt drive pair, the belt may have a little tension and need appropriate tension; the end faces of the two pulleys should be in the same plane; for the coupling drive, the motor shaft and the gearbox shaft must be guaranteed. Concentricity.
2) The gearbox needs a regular oil change. Use 150# (or 220#) medium pressure industrial gear oil. The new machine uses 500 hours to change the oil, and then change the oil every 3000 hours. When the machine has just stopped working and the gearbox is still at a higher temperature, change the oil. After the old oil is discharged, clean the sediment with a small amount of new oil, and clean the filter of the lubricating oil pump, then add new oil to 1/2~2/3 of the liquid level window.
3) The temperature of the barrel and die is usually 150 degrees or more. All fastening screws must be coated with copper disulfide for easy disassembly.
4) The die parts are matched with precision, the separation and assembly need special care and skill, can not be dry, prevent damage and deformation; the fastening screws need to be evenly tightened diagonally, pay attention to concentricity and verticality; multi-die should pay attention to the center of the die Deviation from a distance (<0.1).
5) The storage piston overflow of the storage cylinder die needs to be cleaned regularly, usually about 1 week. The inner core overflow usually needs to be cleaned for 3~5 years, otherwise it will affect the storage stroke and wall thickness control stroke.
6) Regular inspection: gearbox temperature, extrusion motor temperature, barrel root, and cooling jacket temperature, die cooling plate temperature.
7) Safety reminder: The barrel and the die part are high temperatures and the heater terminal is charged. Pay attention to safety during maintenance and prevent it from scalding and electric shock.
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