The re-verification cycle for hot runner sensor preload adjustments varies depending on the scenario. It is essentially divided into two categories: immediate verification before production and periodic re-verification. Specific cycle requirements are as follows:
1. Immediate Verification Before Production After Preload Adjustment
Regardless of the scenario, once the preload adjustment is completed, verification must be performed immediately before mold sealing and production. Production can only begin after confirming that the preload and contact force meet the requirements to avoid subsequent production failures caused by problematic preload adjustments.
2. Periodic re-verification cycle after normal production, adjusted according to production scenario
|
Production Scenario |
Re-verification Cycle |
Description |
|
Routine Precision Injection Molding |
Every 3-6 months/per mold maintenance |
Routine hot and cold cycles have little impact on preload; verification can be performed concurrently with mold maintenance. |
|
High-Temperature/Continuous Production (24-hour uninterrupted production) |
Every 1-3 months |
Long-term continuous hot and cold cycles are more likely to cause preload relaxation; a shorter verification cycle is required. |
|
High-Temperature Injection Molding (Processing temperature > 300℃, such as PVC, PEEK) |
Every 2 months |
Thermal expansion and contraction stress changes are greater in high-temperature environments, making preload deviation more likely. |
|
After the first adjustment of preload for a new mold |
First re-verification 1-2 weeks after production |
After a complete hot and cold cycle for the first time with a new mold, verify whether the preload is stable. After confirming no deviation, verify according to the regular cycle. |
3. The following abnormal situations require immediate re-verification without waiting for the cycle:
If the following situations occur during production, after ruling out issues such as sensor aging and loose wiring, the preload amount needs to be immediately disassembled and re-verified:
Irregular temperature fluctuations exceeding ±3℃; Significantly delayed temperature rise, with a difference in heating time exceeding 30% compared to a qualified sensor of the same specification; Unexplained color differences, dimensional fluctuations, missing glue/flash, or other defects in the injection molded product.
