Vacuum venting mold design for plastic molded parts
There are some regular venting way which are parting surface venting, insert venting, insert pin venting and well-ventilated steel, but there is a special way is vacumm venting, it will need vacumm machine and radiotube, the mold design and manufacturing way will be different comparing with the regular mold;
Vacuum injection molding can reduce the injection pressure, and the low injection pressure can ensure a small residual stress of injection molding, and make less part deformation and warpage. After vacuuming, the cavity is in a vacuum state, with the filling of the melt, there is no other gas source except that the melt itself decomposes and may generate gas, controlling the material temperature and filling speed can improve air trapping issue.

The vacuum mold has the following advantages:
1. Improve the filling effect of the product, eliminate the influence of air on the molding, and fundamentally solve the poor venting issue;
2. The vacuum cavity of the mold is easy to fill, reducing the injection pressure and the back pressure of the injection molding machine;
3. Increasing the injection speed, reduce the molding cycle and improve the production efficiency;
4. Improve the welding line of the product and quality;
5. Eliminate the product defects, burning and bubbles.
For the precision, thin-walled, large flat parts or complex plastic parts, we should eliminate the air effects for injection, otherwise the part quality is unstable, unfull filling, the big injection pressure will cause the deformation and poor surface.
When making vacumm injection molding is used, the surface of the plastic part is smoother and the molding quality is better. Therefore, the application prospect of vacuum injection mold is very common. For example, the smart phones requires products with thin walls, and some parts add glass fiber to increase strength. Generally, what cannot be achieved by conventional injection molding equipment and processes must be produced by high-speed injection molding machines, and the injection molding process must also be adjusted accordingly, and high-speed and high-pressure injection must be used. This brings a great challenge to the exhaust of the mold in a short time. So many molds must be supplemented by vacuuming to complete. Injection molding is a complex process, and many factors must be considered in order to produce high-quality, stylish and high qualiy products.

Slider angle designing tips
Dec 4, 20231. Normally, all the insertion slopes of the slider are not allowed to be less than 3° to prevent excessive self-locking force and scratched; 2. The angle of the locking surface must be bigger than...view
Plastic molding shrinkage rate
Dec 30, 2021Plastic parts getting smaller by shrink, due to the temperature decrease during the molding process, and the shrinkage is expressed by the shrinkage rate, it is common plastic shrinkage rates are...view
Direct gate of plastic injection mold runner system design
Jan 19, 2022In order to get the best injection quality, the gate type must be selected carefully, the coommon gate tyeps are: direct gate, side gate, pin-point gate, sub gate,valve gate of hot runner etc. Among...view
Vacuum venting mold design for plastic molded parts
Mar 23, 2022There are some regular venting way which are parting surface venting, insert venting, insert pin venting and well-ventilated steel, but there is a special way is vacumm venting, it will need vacumm...view
Reasons for making the exhaust system of the injection mold
Feb 28, 2022The gas in the injection mold includes not only the air in the cavity, but also the air in the gate and the decomposition gas generated by the plastic melt, and the steam which caused by plastic in...view
Slider of side core pulling mechanisum assembling
Jul 21, 2022The picture 1 shows a typical guide pin driven slider parting and core-pulling mechanism, we will talk about the composition and function of the lateral core-pulling mechanism. 1. Lateral forming...view
English
русский

_20250310164515A048.webp)

