How to Choose the Best Thermocouple for Hot Runner Systems?

Choosing the correct thermocouple is essential for the stability and service life of a hot runner system. Selection depends on resin type, working temperature range, required response speed, mold structure, and durability expectations. K‑type thermocouples are suitable for most general and high‑temperature applications, while J‑type sensors perform better in low‑to‑medium temperature environments. Sheath materials such as stainless steel and Inconel provide different levels of corrosion and high‑temperature resistance. Ungrounded junctions offer stronger anti‑interference performance, while grounded junctions deliver faster response. Cable length, connector type, and installation method must match the mold design to avoid damage during operation. Compatibility with temperature controllers and hot runner brand systems also affects overall stability. Users must consider long‑term reliability rather than only initial cost. This article provides a complete selection guide, including type comparison, material selection, structural design, and application matching, helping users choose the most suitable and cost‑effective thermocouple and avoid losses caused by improper selection.