Adopting anti-corrosion materials, it can be used as a whole protective sleeve or a two-piece sleeve, or directly treated with anti-corrosion on the protective tube. There are three forms of coating, sintering, and sleeve sealing, which are suitable for measurement in corrosive media of strong acid or alkali. The fixed installation form can be fixed thread, fixed flange (releasing the medium surface), or card sleeve thread, etc., in combination withPVC junction boxes or 316L junction boxes can meet full anti-corrosion requirements. The operating temperature of tetrafluoroethylene can generally reach 200 ℃; If there is severe erosion of the thermal resistance anti-corrosion layer by high velocity measured medium particles on site, surface spraying of wear-resistant alloy can be used; High alumina tubes and corundum tubes can be directly inserted into high-temperature solutions for temperature measurement; Silicon nitride can be directly inserted into various metal solutions such as aluminum solution, copper solution, copper nickel, aluminum nickel alloy solution for temperature measurement, with a temperature resistance of up to 1400 ℃; In special circumstances, titanium tubes, tantalum tubes, etc. can also be used according to the contact medium.