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- Common problems with a non-return valve
Common problems with a non-return valve
Process improvement by understanding how a non-return valve works
This video will go into common problems that occur with a non-return valve in the injection molding process.
The key to trouble-free injection molding of thermoplastic materials with less downtime and improved quality begins before production ever starts. Choosing the appropriate equipment components, then setting up the ideal machine and process conditions, can make or break your bottom line. In the end, it's imperative for the quality of the molded part. This video will dive deep into the common challenges of a non-return valve and provide guidance on how to avoid and solve them.
During the start of the injection phase of the cycle, the non-return valve (NRV) prevents the back flow of material. Because the material can only flow in one direction, the movement and pressure of the injection unit can now be transferred into the material and then into the mold. When the screw is in the plasticizing phase of the cycle, the NRV allows the movement of material to the front screw.
How a non-return valve works
What are the causes of the NRV not closing
How to tell if the non-return valve is leaking during production/when press is not in production
Factors that affect the closing behavior or NRV
Some things to try to get the non-return valve to close more repeatably