Low Extrusion Volume of The Blow Molding Machine: Reasons And Solutions


Today, let’s talk about the reasons and solutions for the low extrusion volume of the blow molding machine.

Customers often report that the extrusion volume gradually decreases after the blow molding extruder is turned on for a period of time.

There are several reasons for the low extrusion volume of the blow molding machine:
1. The cold air has been turned on for a long time, causing the mold surface to be too cold.
At this time, we have to check whether the rubber at the exit of the die surface has been plasticized and melted.

2. The boot temperature is too low.
At this time, it is necessary to check whether the temperature of each part of the extrusion barrel and the die meets the standard requirements. Although the outside temperature of each part meets the standard, if the heating time is not sufficient, the inside and outside temperatures will be inconsistent; check whether there is a heater or thermocouple damaged. If electrical components are damaged, repair or replace them immediately.

3. Excessive temperature of the extrusion barrel or die head, wear of the screw and barrel in the melting section, carbon formation of the screw, and poor feeding.
Check the sensitivity of the temperature controller and deal with it appropriately. The die head temperature controller should be of higher sensitivity.

4. The drive belt is loose or falls off.
The old transmission belt should be replaced immediately, and an idler pulley should be installed if it can be used to adjust the belt tension to prevent the belt from loosening and falling off again.

5. There is glue sticking in the screw feeding part.
Before each shutdown, lower the temperature slightly; wait until the screw feed part is completely out of rubber, and then shut down; when the screw is found to be stuck by the rubber after the start, the screw must be cleaned first. If it is not convenient to clean, Use a plastic rod or a wooden rod to squeeze the material under the feed port forcefully to make the glue sticking to the feed part of the screw move forward. At this time, pay attention to the plastic rod or wooden rod being bitten by the screw, or wood chips falling off, Never use metal rods.

6. There is an agglomeration of glue in the throat of the feeding cylinder.
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, replace it with a new one in time.

7. 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 backpressure.

8. The DC motor voltage fluctuates too sharply.
A voltage stabilizer should be installed to ensure the stability of the voltage.

9. The rotation speed of the clamping roller is uneven, or the pressure between the rollers is too large.
At this time, check whether the clamping rod is eccentric. Is the transmission belt worn or loose? When the pressure between the rollers is too low, slippery will occur. Adjust the air pressure or spring to increase the pressure.

10. Too much-recycled material mixed with crushed.
It is necessary to reduce the proportion of mixed powder and try not to add recycled materials; if you need to add crushed materials, it is best to make pellets first to stabilize the discharge.

The above content is the reason and solution for the low extrusion volume of the blow molding machine.

Write a comment