Ⅰ. Cleaning of extruder screw
1. Remove the extruder screw head, check ring and thrust ring.
2. Use a brass brush to remove the resin residue on the extruder screw, and wipe off the residual melt with a waste cotton cloth.
3. Check the external quality of the different types of extruder screws. If there are small scratches, they can be lightly polished with fine gauze. If there are large scratches, the cause should be found out and corrected.
4. After the screw of the extruder is cooled to normal temperature, wipe off the oil stains on the screw of the extruder with a flux that is not easy to burn.
5. Use the same method to clean the extruder screw head, check ring, and thrust ring.
When cleaning, pay attention not to damage the appearance of the parts. Before installing the screw, apply molybdenum disulfide grease evenly to the screw thread of the extruder screw and the screw head to prevent the thread from rusting and seizing.
Ⅱ. Cleaning of extruder barrel
1. Use a brass brush to remove the resin residue on the inside and outside of the barrel of the extruder, wrap the waste cotton cloth on the end of the long mallet, and wipe off the residual melt on the inside and outside.
2. When the temperature of the barrel drops to 30-50 degrees, lubricate the wet waste cotton cloth with a solvent that is not easy to burn, wrap it around the end of the mallet, and continue to clean the inside and outside of the extruder barrel.
3. Check the quality of the inside and outside of the barrel after cleaning.
4. During cleaning, the nozzle and extruder barrel should be cleaned at the same time.
Ⅲ. How to choose a suitable cleaning method for the screw and barrel of the extruder
When choosing a cleaning method, you need to consider the cleaning conditions, the problems to be solved, and the cost of response.
If the screw barrel of the extruder is already very dirty, the solution is to pull the screw, because the dirty screw cannot be completely removed no matter what you use. Even if it can be completely removed, it will take too much raw material and time.
If you are dealing with a color change, make a judgment first. If changing from white to transparent, just use raw materials to wash. But if toner is added, or red, green, yellow, black, etc. need to be changed to lighter colors, it is recommended to use professional screw cleaning materials to deal with it, especially for hot runners or toners as colorants.
If it is necessary to clean the carbon deposits in the extruder screw, we suggest that carbon deposits should be precautionary. If it is a serious carbon deposit, it is recommended to pull the screw. But for black dot carbon deposits, we believe that the production is mainly caused by downtime, so we must do a good job of protection at the shutdown node, that is, use the screw cleaning material for shutdown maintenance during the shutdown to add the residual resin to the screw, and fully replace the residual resin. This shutdown maintenance material stops in the screw to protect the screw, and it can be replaced with raw materials when it is turned on. It can not only achieve the purpose of cleaning, but also prevent the occurrence of new black spots, which can kill two birds with one stone.
Keyword: sheet metal screws