Thermal shock occurs when components experience rapid, extreme temperature changes, such as during sudden startup, mold changes, or material switches. These abrupt shifts create intense internal stress that can damage sensors, leading to drift, wire breakage, or complete failure. Thermocouples designed for hot runners are specifically engineered to resist thermal shock and maintain stable performance.
Mineral-insulated construction provides excellent resistance to rapid temperature changes. The compact, sealed structure reduces internal stress caused by expansion and contraction, protecting the sensing alloy wires. High-quality junctions, often laser-welded, further improve durability against sudden heating or cooling. Standard low-grade thermocouples often fail quickly under thermal shock due to weak internal connections and poor insulation.
In practical production, thermal shock commonly happens when switching between cold and hot materials or during emergency restarts. Reliable thermocouples maintain calibration and signal stability through these events, ensuring the process recovers quickly without defects. Resistance to thermal shock extends service life, reduces maintenance, and improves process resilience in dynamic production environments.
