1. Wipe the depth micrometer clean before use, and then check whether its moving parts are flexible and reliable: the differential cylinder should rotate flexibly in the full stroke, the differential screw should move steadily, and the locking device should function reliably.
2. Select and replace the measuring rod according to the measured depth or height.
3. The 0-25mm depth micrometer can directly check the zero position: use the 00-level platform to clean the platform, the datum plane, and the measuring surface of the depth micrometer, and rotate the differential cylinder to make its end face fall outside the zero line of the fixed sleeve, then stick the datum plane of the micrometer on the working surface of the platform, press the base with the left hand, and slowly rotate the ratchet with the right hand, Check the zero position after the measuring surface contacts the working surface of the platform: the zero graduation line on the differential cylinder shall be aligned with the vertical graduation line on the fixed sleeve, and the end face of the cone surface of the differential cylinder shall be tangent to the zero graduation line of the sleeve.
4. For depth micrometers with a measuring range of more than 25 mm, the zero position shall be checked with a check gauge (which can be replaced by a gauge block): the working surfaces of the check gauge and the platform shall be wiped clean, the check gauge shall be placed on the platform, and the datum plane of the depth micrometer shall be stuck to the zero position of the check gauge.
5. When using a depth micrometer to measure blind holes and deep grooves, the hole and groove bottom are often invisible, so be careful when operating the depth micrometer and avoid using force recklessly.
6. When the diameter or slot width of the measured hole is larger than the base of the depth micrometer, an auxiliary positioning reference plate can be used for measurement.
