Tube skin thermocouples on 9 large ethylene furnaces were experiencing a 40-50% failure rate within 6 months of installation. They were also seeing large drift patterns of those thermocouples before they failed.
Thermo Sensors fabricated, for test, our proprietary “K” thermocouple to the quality standards for insulation resistance testing that would continue to meet ASTM e608 (500vdc @ 1 Gigohm). Then, follow an established tube skin thermocouple installation procedure.
Since then, we have installed duplicate sets of 16 each “K23” Thermo Sensors tube skin thermocouples in 8 of the heaters (128 total). To date, the thermocouples are still reading with extreme accuracy and without a single failure.