How High-temperature Resistant Thermocouples Adapt To Special Engineering Plastics

Special high-temperature engineering plastics such as PEEK, LCP, PPS and PA46 are commonly utilised for high-temperature resistant automobile parts, electronic insulation components and industrial precision parts. They are moulded at a temperature of as high as 400°C to 450°C, which is well beyond the long term operating limit of ordinary medium and low temperature thermocouples. Ordinary thermocouples will quickly oxidise, drift and fail in such harsh situations. Professional high-temperature resistant hot runner thermocouples rely on unique alloy formulations and structural techniques to adapt to ultrahigh temperature working conditions.

High-temperature resistant thermocouples use imported materials Inconel alloy sheath and vacuum smelted nickel-chromium superalloy sensor core, which may be stable thermoelectric linearity for a long time above 450degC without crystal structural changes and oxidation attenuation. The internal insulation employs high purity magnesium oxide ceramic filling, which still maintains outstanding insulation performance and pressure resistance under ultrahigh temperature, avoiding the leakage of signal and the failure of short circuit. The complete body adopts laser seamless welding, totally sealed structure, to isolate the high temperature volatile gas erosion, prevent the internal alloy wire corrosion and oxidation.

Conventional J type thermocouples will lose all measurement precision totally while working above 350°C for a long time, and the usual K type likewise has obvious drift above 400°C. The customised models for high-temperature adjust the alloy ratio, suppress the high-temperature potential drift and adopt the matching special compensation algorithm of the high-temperature controller to ensure that the temperature measurement error is controlled within ±0.5°C for a long time. It can properly record the small temperature fluctuations of the runner, stabilise the melt viscosity of specific engineering plastics, and prevent breakdown, carbonisation and unbalanced filling caused by ultrahigh temperature deviation.

Besides, the high temperature resistant thermocouples are provided with the high temperature anti-aging leads and radiation protection structure to adapt to the long-term high temperature baking and harsh heat radiation environment of the runner. Moulders making special high temperature plastics that naively use regular thermocouples will find that it leads to frequent failure, high scrap rate and recurrent mould maintenance. The matching of high temperature resistant thermocouples is the essential assurance to give full play to the moulding performance of special engineering plastics and to stabilise long-term production.