Permanently installed 02 level probe for furnace atmos. - has hydraulically operated reciprocating cover clearing access for calibration gas supply

摘要

O2 partial pressure in the atmos. of a heat-treatment furnace is measured by a probe with a spherical reaction element (6) between a U cross-section outer electrode (7) and an axial inner electrode (9), both electrodes and the element (6) being held within a steel sleeve (1) inside a cover cover tube (10), mounted on a fixed flange support (12) in the furnace wall. Aligned apertures (2,3) in the steel sleeve and between the electrodes form a flow path for furnace atmos. when the cover tube as below a certain level. The probe foot (13) can be raised and lowered by a hydraulic cylinder (17) contg. a double-acting piston (18) in one position the sensor is contacted by furnace gas, while in a second position the flow path is barred, and the sensor is bathed with suitable celebration gas from a cylinder (25). admitted by a valve (23) into the probe foot to rise towards the reaction element. USE ADVANTAGE - For probes used at high temp. eg 1150 deg.C and possibly in aggressive atmos. Probe can be easily and precisely celebrated without removal or dismounting.