Molds & Tooling
2 views
PPS Check Valve and Retention
Problem Phenomenon
Metering fluctuates, part weight is unstable, and cold material spots occasionally appear at the nozzle
Cause Analysis
PPS melt viscosity is relatively low; check valve failure causes melt backflow and inaccurate metering; cold material from the nozzle section enters the cavity forming cold material spots; regular inspection of the check valve is the safeguard
Solution
①Regularly inspect the sealing function of the check valve; ②Control nozzle temperature independently to prevent cold material; ③Include metering fluctuation in equipment inspection items; after adjustment, take continuous samples to verify the effect, and resume mass production only after confirming stability
Key Takeaway
The low viscosity of PPS amplifies the impact of check valve failure; behind metering stability lies valve health; after confirming effectiveness, fix the parameters and practices into the work instruction to prevent recurrence
Was this helpful?
0 people found this helpful
Thank you for your feedback!