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.

Hydraulic diameter conversion of runners in plastic mold gating system design
Jan 13, 2022Hydraulic diameter refers to 4 times the ratio of the flow cross-sectional area to the perimeter, as the wall shear stress of non-circular pipes is not even distributed along the surrounding walls,...view
The design principle of the exhaust slot
Mar 6, 2022The exhaust system of plastic molds is also very important, if the product has air trapping or exhaust system is not suitable will have a big impact on injection molding production and product...view
The main design points of the design of the plastic mold pouring system
Jan 11, 2022The main runner is the part where the molten plastic first passes when it is sprayed from the injection nozzle, and it is coaxial with the injection nozzle, because of repeated contact and collision...view
Plastic injection mold common cooling gate
Feb 17, 20221. Straight-through cooling water gate: the straight-through cooling gate is the most commonly used gate for plastic injection mold, and it is also the most convenient type of cooling for processing....view
What is Ejection Molding?
Dec 28, 2021The process to get injection molded products is called injection molding, or called injection. Injection molding is an important method in polymer molding processing, it is characterized by a short...view
Gate position determination of plastic injection mold runner design system
Jan 17, 2022In the selection of gate location, the following issues should be paid attention to: 1. The gate position should be set at the maximum wall thickness of the plastic part, so that the plastic melt...view
English
русский



