Reasons and solutions for too little extrusion of horizontal injection molding machine
Today, let's talk about the reason and solution of the horizontal injection molding machine's too little extrusion.
Customers often report that the extrusion volume of the horizontal injection molding machine is gradually reduced after a period of time after the horizontal injection molding machine is turned on. This is mainly caused by the following reasons:
The first reason is that the cold air has been on for a long time, causing the mold surface to be too cold. At this time, we need to check whether the plasticization and melting of the rubber at the exit of the mold surface has been completed.
The second reason is that the start-up temperature is too low. At this time, it is necessary to check whether the temperature of each part of the extrusion barrel and die meets the standard requirements? Although the outside temperature of each part reaches the standard, if the heating time is not enough, the inside and outside temperatures will be inconsistent; check whether there is a heater or thermocouple damaged? If any electrical components are damaged, repair or replace them immediately.
The third reason is that the temperature of the extrusion barrel or die is too high, the screw and barrel of the melting section are worn, the screw is carbonized, and the feeding is not smooth. Check the sensitivity of the temperature controller and deal with it appropriately. The die head temperature controller should be of higher sensitivity.
The fourth reason is that the transmission belt is loose or falling off. The old transmission belt should be replaced immediately. If it is still used, an idler pulley should be installed to adjust the belt tension to prevent the belt from loosening and falling off again.
The fifth reason is that there is glue sticking to the screw feeding part. Before stopping each time, the temperature should be lowered slightly; wait until the screw feeding part is completely out of glue before stopping; after starting the machine, it is found that the screw is stuck with the glue. When cleaning, the screw must be cleaned first. When it is really inconvenient to clean, use a plastic rod or wooden rod to squeeze the material under the feed port to make the rubber sticking to the feed part of the screw move forward. At this time, pay attention Plastic rods or wooden rods are bitten by the screw rods, or wood chips fall off. Never use metal rods.
The sixth reason is that there is agglomeration of rubber in the throat of the feeding cylinder, and the water temperature of the cooling water jacket at the throat of the feeding cylinder should be controlled below 40C°. If the filter is clogged, it must be replaced with a new one in time.
The seventh reason is that the back pressure is too low. The phenomenon caused by the back pressure is too low. The discharge is unstable, which can be corrected by increasing the back pressure.
The eighth reason is that the DC motor voltage fluctuates too sharply. A voltage stabilizer should be installed to ensure the stability of the voltage.
The ninth reason is that the rotation speed of the clamping rod is uneven, or the pressure between the rollers is too large. At this time, check whether the clamping rod is eccentric? Whether the transmission belt is worn or loosened off; when the pressure between the rollers is too low, slippery will occur, the air pressure or spring can be adjusted to increase the pressure.
The tenth reason is that there are too many recycled materials mixed with pulverized materials. It is necessary to reduce the proportion of mixed powder materials and try not to add recycled materials; if pulverized materials need to be added, it is best to make granular materials first to stabilize the discharge.