I. Standard Cooling Time for New Parts
Applicable Scenario: Brand new, undamaged hot runners, after 8 hours of standard preventative baking according to specifications, with an insulation resistance ≥20MΩ after drying.
Cooling Time: Natural cooling to below 60℃ takes approximately 1-1.5 hours, after which they can be directly installed and wired without additional waiting.
II. Cooling Time for Slightly Damaged Hot Runners
Applicable Scenario: Hot runners exposed to a humid environment for 2-4 hours, after 12 hours of baking to remove moisture.
Cooling Time: Natural cooling for 1 hour, after a retest of the insulation resistance showing no drop, they can be installed. The total cooling time should not exceed 1.5 hours.
III. Cooling Time for Moderately to Severely Damaged Hot Runners
Applicable Scenario: Hot runners with condensation on the surface, after 16-24 hours of deep baking for thorough dehumidification.
Cooling Time: Natural cooling for 1.5-2 hours. After two consecutive retests confirming the insulation resistance is consistently ≥30MΩ and there is no moisture reabsorption, the device can be installed.
IV. Cooling Time Adjustment Rules for Special Environments
In high-humidity environments such as the plum rain season/return to spring, the cooling process must be completed in a dry room. The cooling time is uniformly shortened to 45 minutes to avoid prolonged exposure and secondary moisture absorption.
For large multi-cavity hot runner plates, the cooling time is increased by an additional 30 minutes to ensure the internal temperature of the runner plate drops uniformly to below 60℃, preventing burns to installation personnel.
Forced cooling methods such as direct fan blowing and water cooling are prohibited to avoid sudden cooling deformation of the hot runner metal components, which could lead to sensor displacement and leakage at the sealing surface.
