Author: mgg-Plastic bottle manufacturer
1. The range of tolerances that exceeds the standard requirements of the size of the bottle size. Main reason: (1) The plastic raw material has moisture, causing contraction to increase. (2) The molding process conditions have changed; (3) The temperature when the temperature is measured and the temperature at the time of use.
CAUSE Dimensions change, resulting in an increase in errors. Some plastic grams are identical, but it is not equal to the systolicity, and it is easy to cause contraction deviation. The main factor affecting the size of the shrinkage is the bottle cooling temperature and cooling time, so it needs to be strictly grasped; When measurement, the ambient temperature is also easy to cause changes in the size of the bottle, generally stored in a 2 ° C of 23 ° C for 48 hours, and the size is stabilized and then measured. Solution: The plastic raw material is required for drying treatment when the bottle is out of normal, and the drying temperature and drying time are determined.
The value of the molding process parameters should be improved from the temperature of the injection pressure, holding pressure, and the temperature of the cooling mold should not be higher than 50 ° C, and the cooling time is appropriately extended, which facilitates the bottle body to obtain a smaller shrinkage, and eliminate the storage of room temperature. Deformation, and enable the size of the bottle body to be high, thus ensuring the overall quality of the bottle body. 2. The surface of the bottle has impurities (black spots): (1) The melt temperature is too high, the raw material is overheated; (2) the paste mixing mold at the mouth of the mold; (3) In the raw material mixing process Mixed foreign matter: (4) The plastic itself is not clean (bulk). Cause Analysis: Because the injection molding cycle is long, the plastic is decomposed in the cartridge, which is easy to produce a black class.
In order to reduce the residence time of the plastic in the fuse tube, the actual injection amount and the barrel capacity should have a certain proportion, and the ratio cannot be less than 15%. Solution: Reasonable selection machine simplification, the machine is mainly from the addition of the external thermocouple of the barrel, and is divided into three districts, ie the feed zone, the compression area, the metering area, and the temperature ratings should be from the feed zone of the barrel to compression. The district to the metering zone gradually warmed to form a certain temperature gradient to ensure that the material is not thermally decomposed. It is necessary to clean up the tissue paste, and screen the non-clean raw materials.
3. Main causes of fever and hindle modules: (1) Injection pressure is too high; (2) deficiencies in the formula; (3) The mold in the mold and the inlay portion are adversely: 4) There is a debris between the billet. CAUSE It is easy to deform or misalignment, resulting in flying edges, and should reduce the injection pressure. Solution: In adjusting the process parameters to reduce plastic fluidity and adjust the process conditions, mainly reduce injection pressure, melt temperature, and mold temperature, injection speed, and noise temperature.
4. The amount of injection of the blank is insufficient.