Abstract: A temperature-measuring instrument especially for measuring high temperatures in pressure reactors. It comprises a sheathed thermocouple which is mounted in an inner ceramic element which is closed at one end. This inner element is inserted into a molybdenum element which is also closed at the same end and is surrounded in turn by an outer ceramic element. The annular space between the molybdenum element and the ceramic element is filled with a pressed ceramic mass. A flanged joint joins the molybdenum element to a ball joint which is in turn joined via bellows to a pressure-resistant bushing.

Abstract: A system for the measurement of temperatures in a reactor such as those operated under high pressure and/or temperature is disclosed. The temperature is measured by the use of a pyrometer which is in optical communication with a measuring duct which can be disposed in the wall of the reactor and is in optical communication with the reactor interior. The measuring duct comprises two concentric tubes the outer one of which extends beyond the inner tube in the direction of the reactor interior and has a conical construction immediately following the termination of the inner tube. The concentric tubes are provided with a common end section such as in the form of a cone in the direction of the reactor exterior. A hermetic housing defining a safety chamber is disposed exterior thereof, the hermetic housing having two opposed pressure type and heat resistant windows in alignment with the inner tube and the pyrometer. The hermetic housing is not normally permanently attached to the measuring duct.

Abstract: A method and apparatus for directly measuring the interior temperature of a pressurized reactor includes a temperature sensor movable along a measurement channel between a measurement position within the reactor and a retracted position outside the reactor, a drive system for selectively reciprocating the sensor along the channel, and a device in the channel intermediate the measurement and retracted positions for closing the channel when the sensor is at the retracted position.