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.

USM Blogo Opening
Oct 27, 2021Hello everyone! Our blog is open today, it is very glad to have the opportunity to meet you here, welcome to visit us whenever you need. USM is a professional plastic injection mold and molding...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
Well-ventilated steel of venting design for molded parts
Mar 14, 2022Well-ventilated steel is a sintered alloy, iIt is a porous material sintered with spherical particle alloys, the pore size is 7-10μm and the strength is poor, but the texture is loose which allow the...view
Banana gate of plastic injection mold runner system design
Feb 7, 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
Plastic injection mold runner system design points
Jan 9, 2022When designing the gating system, Firstly, we should consider making the plastic melt fill the cavity with core side quickly to reduce pressure and heat loss; secondly, it should be economically...view
Different treatment of plastic injection mold cooling system principles
Feb 22, 2022Different treatment principle: 1. The mold temperature is different according to the different plastics, when the plastic requires the molding temperature of the mold to be ≥80°C, the mold must be...view
English
русский



