How Does The Mold Temperature Affect The Product?
In our usual production process, when some products are relatively small and the requirements are not very high, it does not seem to have much effect if no cooling water is connected. For example, the plastic injection mold is cracked, and the cracked place happens to have a waterway through it. There is really no way to repair it, and it can only be produced without water.
Some may not need to increase the cooling time, and some need to increase the cooling time, resulting in the entire production. The cycle becomes longer and the production efficiency becomes lower.
However, in the case of very high product requirements of plastic injection mold, don’t say to receive water, that is, after receiving water, the fluctuation of water temperature of injection molding still plays a vital role in the impact of the injection molded product.
If the appearance and size requirements of the injection molded product are not very high, the mode of filling the plastic injection mold with low mold temperature is generally used, which can shorten the cooling time, so as to achieve the purpose of improving injection molding production efficiency.
The mode of filling the injection mold with high mold temperature can make the product cool it is uniform and can prevent internal stress and rupture caused by the excessive temperature difference, as well as improve the product’s flow marks and bonding lines.
In general, the high mold temperature needs to be guaranteed by external equipment. Nowadays, more plastic injection molds are used on the market, such as mold temperature machine. The mold temperature machine can be divided into water type and oil type.
The standard water type mold temperature machine works The maximum temperature is 120℃, and the high-temperature water mold temperature machine can work up to 180℃. Using the mold temperature machine can make the plastic injection mold reach the set temperature and keep the mold temperature constant.
High mold temperature has the following advantages
Conducive to stable dimensions
Since the mold temperature is constantly controlled, the injection-molded product shrinks evenly, and the relative product size is easier to control, which is beneficial to improve the dimensional accuracy.
Facilitates the filling of the cavity
For plastics with poor fluidity and high viscosity, increasing the mold temperature can improve its filling performance and save production cycle time. The fast filling can greatly improve the product’s flow marks, bonding lines, and other bad conditions.
Help to get the best appearance
The lower the mold temperature, the faster the plastic cools in the plastic injection mold, and the relative fluidity becomes worse. Adding the mold temperature can get a better injection mold parts appearance and restore the traces on the surface of the mold. The polished finish of the mold will be completely expressed all over the product.
Conducive to the release of the molded product
For transparent plastic injection molding products, the male mold cavity with high mold temperature or the heart shape of the slider has a tighter clamping force than the low mold temperature products, especially the vacuum adsorption products.
High mold temperature has the following disadvantages
- High mold temperature will enhance the fluidity of the plastic and will cause the generation of burrs.
- Due to the high mold temperature, the gap between the movable (sliding) moving parts may be stuck or the live (sliding) will not move smoothly after the mold is thermally expanded.
- High mold temperature will dissipate heat into the air and on the injection molding machine, which is not conducive to the constant temperature and control.
Generally, in order to prevent the loss of mold temperature, heat insulation plates can be installed on the fixed plates of the male and female molds.
- The high mold temperature will cause the oil stain inside the male mold and the thimble or the interior of the insert to leak out, affecting the appearance quality of the product. For transparent, white, or light-colored products, eight pieces must be unloaded before the production, and the plastic injection molded parts Disassemble and clean them all.