Water-based mold cooling coolant splashes and atomizes during daily injection demolding and mold temperature control circulation for domestic and Husky auto part hot runner mold; inferior unqualified coolant containing corrosive chloride and acidic additive produces floating corrosive mist which continuously erodes nearby exposed thermocouple sheath and wiring insulation layer, accelerating premature aging failure of temperature sensing components. Fine coolant fog suspended in air adheres to thermocouple probe surface and condenses into liquid film under temperature alternation; chloride component inside liquid gradually causes pitting corrosion on ordinary 304 stainless steel sheath, corrosion spot expands inward year by year until penetrating sheath wall and destroying internal magnesia insulation layer.
Ordinary fiberglass outer insulation wire absorbs condensed acidic coolant liquid and gradually becomes swollen, pulverized and lose insulation performance; short-circuit accident easily occurs when bare core wire touches mold metal frame. High-quality anti-rust neutral coolant with low chloride content can greatly reduce such corrosion damage, but many small workshops select cheap inferior coolant to cut production auxiliary material cost regardless long-term thermocouple replacement loss.
Standard workshop operation installs splash-proof baffle between mold cooling channel and hot runner thermocouple fixed position to block direct coolant splash; regular weekly maintenance cleans probe and wire surface accumulated coolant residue with neutral cleaning fluid, effectively slowing down corrosion deterioration speed and extending average service life of nearby thermocouple.
