Corrosion Resistant Sensors. Where there is a requirement to measure the temperature of highly corrosive processes, Pyrosales can provide a thick teflon sleeve which covers all the wetted parts of the thermowell. Teflon is an ideal material if the temperatures are not high as it is resistant to most strong acids. It has been usual to use a teflon dip coat, however we these are only thin coatings that are easily damaged and as such provide no protection. By providing a thick sleeve sized to fit the OD of the thermowell, you can protect your sensor and maintain control of your process temperature. Contact our Sales Department so that we can advise on the options available.