This is a frequently encountered problem. When professional injection molding cannot be solved through technical means, it can be improved through mold design and manufacturing, and usually can be solved.

The melting position of the screw of the injection molding machine reaches the set value, and when the pressure is maintained to complete the injection molding, the position is 0 (residual glue amount is 0). Possible reasons:

1. Leakage of glue. In this case, professional injection molding first checks whether the injection molding machine barrel leaks. Is there any leakage in the fitting position between the nozzle of the injection molding machine and the main liner of the mold. If there is a leakage of glue, it is a natural phenomenon, that is, if the product is not satisfied with the glue, it should be eliminated. The following checks should only be performed when it is confirmed that there is no leakage of molten adhesive. When professional injection molded products are not filled with glue and there is no glue leakage, it may be due to insufficient glue. At this point, it is necessary to increase the melting stroke and the amount of glue. After increasing the melt stroke, continue to inject while observing the residual glue amount of the screw, the melt stroke, and the amount of glue applied to the product.

2. Insufficient amount of glue. In professional injection molding, increasing the melt stroke results in an increase in the supply of adhesive for the product, indicating a shortage of adhesive and the need to increase the melt stroke. When the melting stroke is reached and the product is still not filled with glue, you need to replace it with a larger model of injection molding machine.

3. The glue leaks through the glue mesons. If the amount of glue in professional injection molded products does not increase correspondingly with the increase of melt stroke, it may be a glue leak from the injection molding machine.

The method to check for glue meson leakage is to keep the product with a certain injection cycle in the mold cavity and switch to manual injection. The injection pressure increases from small to large. Observing the progress of screws can determine the leakage of mesons. When manually injecting glue into professional injection molding, the screw will not move forward, indicating that the glue is well sealed and will not leak glue. Allow the screw to advance slightly at higher injection pressures. At this point, it is not the leakage of the melt, but the shrinkage of the melt under pressure.

When professional injection molding products are not satisfied with the glue, the first thing to check is whether there is any leakage between the injection molding machine barrel and the injection molding machine nozzle mold; Secondly, check if there is any glue leakage at the front end of the injection molding machine screw. Only after excluding these two conditions can other judgments be made.