Calibration requirements and methods for coating thickness gauges
Standard thickness gauges are thickness standards used for calibrating coating thickness gauges to determine the display value error and display value variability or to calibrate coating thickness gauges. Coating thickness gauge calibration conditions, testing room temperature: 20 ℃ ± 2 ℃, thickness slice and block temperature equilibrium time: 2h; testing room humidity: ≤ 65% vertical optical meter warm-up time: not less than 15min Instrument power supply: 220 (1 ± 10%) V, 50Hz.
1 Appearance
Requirements: the thickness of the two surfaces of the sheet should be free of scratches, bumps and other defects Calibration method: visual observation.
2 Effective area
Requirements: the uneven surface should be marked with a circle area of radius greater than 5mm, and the area of the thickness sheet on the even surface should be not less than 20mm x 20mm. calibration method: steel ruler measurement.
3 number of the average value.
Calibration method: with three equal blocks and vertical optical meter, with a direct method or comparative method to measure the thickness of the standard thickness slice, before measuring the application of aviation gasoline to clean the block, thickness slice, optical meter anvil, probe, calibration of the use of the cap radius of curvature is not less than 20mm, the measurement of the rod should be down through the pitchforks so that the cap gently in contact with the standard thickness slice to prevent the standard thickness slice of the impact of the calibration point for the effective area within the Uniformly distributed 5 points (including the centre), no effective area marking of the standard thickness piece of the effective area in the centre as the centre of the circle radius of not less than 10mm within the circle.
4 uniformity error
Requirements: uniformity error of the standard thickness slice. Calibration method, take the thickness of each point readings and thickness of the average value of the zui big difference for the standard thickness slice uniformity error, the value shall not exceed the requirements of Table 2.
