Vacuum Negative Pressure Adsorption Technology
Immetech and CUMSA providing solutions to injection molding problems
Injection molding technology has been developing rapidly in recent years, and consumers have increasingly high expectations regarding the function and appearance of products. Due to the requirements for high impact resistance and zero welding lines, the production of many large plastic items calls for the adoption of vacuum adsorption technology to achieve success. Immetech, together with vacuum negative pressure adsorption solutions provider CUMSA, has delivered a series of innovative solutions over the past three years for customers around the world, bringing high-quality molds and products to our client base. The molding cycle time has been shortened, and product defect rates and production costs reduced. For example, 5-star car seats for Dorel; complex automotive parts for Honda; high-end mobile accessories for China Mobile.
Core technology: Solving the air trap and eliminate welding line issues in mold
When molds are filling at high speed, a common issue is the air trap, caused by a combination of the complex part structure and the principles of fluid mechanics. Air trap locations are usually in areas that fill last, so molds need to be designed with adequate and effective venting. Too few or poorly-located vents are a common cause of air traps and defects.
What is the advantage of the CUMSA Vacuum System?
The CUMSA vacuum system removes air from the cavity before the plastic is injected, creating a negative pressure that allows filling in a fraction of a second. It can shorten the molding cycle time, solve the problem of welding lines associated with multiple filling, avoids product air trap and burning, and reduce injection pressure.
How to design and install Vacuum Pulling System into mold?
The most important thing is to ensure perfect sealing, and select the best location for the vacuum system. The illustrations below show the vacuum system in cavity side, VG.523016, for our 5-star Car seat for Dorel. Delivering a powerful vacuum negative pressure function, following here are the working procedures when the mold is set up in the injection machine:
- Closing the mold starts the vacuum system extracting air from the cavity; vacuum is achieved through the venting channel in the mold (60L/min)
- After filling is completed, mold opened and parts ejected, the vacuum system in cavity side will close and stop
- The blowing-out function is performed through the venting channel inside the mold (6 bar) before ejecting the product
- When the mold is closed in the next shot, the vacuum system starts up again to repeat the above procedures
Watch this demonstration video from CUMSA showing the creation of a vacuum in the cavity of a plastic injection mold.
Contact the Immetech Team with your technical support requirements! Our team is highly trained in mold design, including scientific molding and large and complex mold design. We have built many complicated and large-format molds, making use of technologies including RJG sensors, CUMSA vacuum systems, Bauer gas unit and in-mold degating systems, and more!