In the hot runner accessory market, a large number of counterfeit and shoddy thermocouples flood in, which are low in price but short in service life, unstable in temperature measurement and easy to cause production failure. It is essential for mold manufacturers and injection molding enterprises to master simple and effective identification methods. Firstly, distinguish from appearance and processing technology. Formal qualified hot runner thermocouples adopt precise numerical control processing, smooth probe surface, uniform thread specification, tight welding junction and neat and flawless wire arrangement. While imitation products have rough surface, uneven welding spots, thin protective casing and obvious burrs on structural parts, with poor overall fineness.
Secondly, identify through internal material and structural design. Standard thermocouples use high-density high-temperature resistant insulating filler inside, which is compact and high temperature resistant, not easy to melt and deform under long-term high temperature. Inferior products are filled with cheap ordinary insulating materials, which will soften and lose insulation effect above 280℃, easily causing internal short circuit. High-quality products are equipped with thickened anti-oxidation protective sleeves, while fake products use thin ordinary casings that are prone to aging and cracking.
Thirdly, test practical temperature sensing performance. Under the same high-temperature environment, connect the thermocouple to a standard temperature controller for heating test. Genuine products respond fast, stable in temperature rise data, small in fluctuation and consistent with actual measured temperature of infrared thermometer. Counterfeit thermocouples show slow temperature response, large data swing, obvious temperature drift after short-time use, and inconsistent temperature display of repeated tests.
Fourthly, check brand certification and parameter marking. Regular supporting thermocouples of well-known hot runner brands are clearly marked with model specification, temperature resistance range, wire standard and production batch number, complete with factory inspection report and quality guarantee certificate. Imitation products are vague in marking, incomplete in parameter information and lack formal quality certification. In addition, judge from service life and after-sales service. Genuine thermocouples can work stably for more than 8 to 12 months under normal working conditions, with perfect after-sales replacement and maintenance services. Low-cost fake products often fail within 1 to 3 months, with no effective after-sales guarantee. Choosing formal authorized suppliers and refusing ultra-low-price inferior accessories is the fundamental way to avoid losses caused by unqualified thermocouples.
