A Comparison-Calibration Apparatus Covering the Range 500°C to 1000°C

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A Comparison-Calibration Apparatus Covering the Range 500°C to 1000°C (204.97 KB)

A comparison-calibration apparatus covering the range 500°C to 1000°C was developed. The core of the apparatus is made from a three-well, high-temperature equilibration block. Copper was chosen for the equilibration block because of its thermal conductivity. At high temperatures, copper oxidizes, but this problem was solved by sealing the copper block with argon gas in a silica glass shell. For SPRT calibrations, platinum thimbles were used in the block to protect the SPRT elements from contamination. Test results show the apparatus has excellent horizontal and vertical temperature gradients, and is well suited for comparison calibration of resistance thermometers and thermocouples.