Measuring device of process automation technology for ascertaining and monitoring a chemical or physical process variable in a high temperature process in a container

摘要

An apparatus forming a measuring device for ascertaining and monitoring a chemical or physical process variable in a high temperature process in a container, wherein the measuring device is formed from at least a sensor element located in the process and at least a measurement transmitter located outside the process. At least a first sealing element is provided for sealing against penetration of process medium into the sensor element. The sensor element has a boundary location between a first sensor element region, which faces the process and which is embodied with a high thermal resistance, and a second sensor element region, which faces away from the process and which has a low thermal resistance, and that the temperature sensitive element is arranged in the sensor element at the boundary location.

主权项

1. An apparatus formed as a measuring device of process automation technology for ascertaining and monitoring a chemical or physical process variable in a process at a temperature greater than 200 degrees Celsius in a container, comprising:
at least a sensor element located in the process; and at least a measurement transmitter located outside the process, wherein: at least one temperature sensitive element is provided in said sensor element; said sensor element has a boundary location between a sensor element first region, which faces the process and which is embodied with a first thermal resistance, and a sensor element second region, which faces away from the process and which is embodied with a second thermal resistance; and said at least one temperature sensitive element is arranged in said sensor element at said boundary location; wherein said first thermal resistance is greater than said second thermal resistance, wherein said first thermal resistance in said first region of said sensor element is implemented via a geometry change by reducing a first cross sectional area of said sensor element to such a degree that the sensor element still withstands any process pressures, and said second thermal resistance in said second region of said sensor element is implemented via a geometry change by increasing a second cross sectional area of said sensor element to the extent permitted by pressure and temperature specifications of the sensor element so that an abrupt lowering of the thermal resistance is achieved.