Verification of Dimensional Accuracy
The full length of the hole is smoothly and without snagging or binding a regular nylon "Go" gauge. The inner diameter tolerance and coaxiality deviation are verified to be ≤0.05 mm, fulfilling the initial design requirements.
Verification of Temperature Sensing Performance
The mended hole is completely filled with a freshly calibrated sheathed probe. For thirty minutes, the system is heated to the hot runner's typical working temperature. For comparison, a calibrated standard contact thermometer is utilised; there must be no continuous unidirectional drift and a variation of ≤±1°C between the temperature controller reading and the measured temperature.
Verification of Operational Stability
There are three successive cycles of heating and cooling (from ambient temperature to 600°C). The temperature signal exhibits no abrupt jumps or anomalous variations during the operation, and the temperature uniformity deviation is ≤±1.5°C, which satisfies hot runner temperature control accuracy requirements.
Verification of Installation Compatibility
The outer wall of the sheath fits precisely against the inner wall of the hole without becoming loose, and the sheathed probe may be put in and taken out without binding. Retesting verifies that there is no chance of electrical leakage since the insulation resistance between the housing and the sheath terminals is ≥100 MΩ.
The component is authorised for regular production usage when all tests are successfully completed and the accuracy of the repaired temperature-sensing hole is verified to satisfy specifications.
