③Because the small gate has a small volume and fast freezing, when producing certain products, it is not necessary to wait for the entire solidification of the product after the small gate is frozen. As long as the external cured layer has sufficient strength and rigidity, the product can be demolded, thereby Shorten the molding cycle and improve production efficiency.

④In the multi-cavity unbalanced pouring system, if the small gate is used, the flow resistance of the gate to the plastic melt will be much greater than the flow resistance of the multi-channel melt, so it may be filled in the melt After the flow channel has established enough pressure, each cavity can be fed and filled at approximately the same time. Therefore, the small gate can balance the feeding speed of each cavity in the multi-cavity cavity, which is beneficial to the balance of the pouring system.

⑤If you use a larger gate molded product, in the case of higher surface quality requirements, you often need to use appropriate tools or machine tools to post-process the product to remove the gate scars, especially when the gate is too large, the gate Aggregate must also be removed by sawing, cutting, etc. However, this trouble can be avoided when using a small gate. For example, the small gate condensate can be quickly removed by hand, or it can be automatically removed by a special mold structure during demoulding. In addition, the scar after the small gate is removed is generally small, and it is generally not necessary or only needs a little trimming and polishing work. Therefore, the use of a small gate is not only conducive to the separation of the condensate from the pouring system and the product, but also to the repair of the product.

However, it should be noted that although a small gate has the above-mentioned advantages, an excessively small gate will cause a large flow resistance, resulting in a prolonged filling time of the feed. Therefore, some plastic melts (such as polyformate and polysulfone) with high viscosity or shear rate that have little effect on the apparent viscosity should not be formed by small gates. In addition, when molding large products, you should also pay attention to enlarge the gate cross-sectional area accordingly, and sometimes even need to enlarge the gate cross-sectional height to close to the maximum thickness of the product to improve the melt fluidity. In addition to the above, for products with a large wall thickness and a large shrinkage rate, it is generally required to have enough time to shrink, so in this case, the gate cross-sectional area can not be designed too small.