The accuracy of the Sanfeng micrometer is calibrated before leaving the factory, and under normal circumstances, there is no need for recalibration. To avoid errors caused by transportation, storage, and other factors, it is best to calibrate before use to ensure measurement accuracy.

Environmental temperature: 20 ° C ± 1 ° C

(Please ensure that the micrometer and the following tools have fully adapted to this ambient temperature before proceeding with accuracy confirmation)

The required tools are as follows: gloves, micrometer stand, flat crystal, parallel crystal

The calibration steps are as follows:

1. Wear gloves and fix the micrometer onto the micrometer stand. Rotate the micrometer screw throughout the entire stroke to confirm if there are any stuck or uneven movements.

2. Clamp white paper between two measuring surfaces to remove dust from the measuring surface.

3. After slowly closing the two measuring surfaces, rotate the ratchet pressure device 3-5 times (1.5-2 turns) and confirm the base point (the base point of 0-25mm is 0).

   (Note: If the ratchet pressure device rotates too fast, it may affect the accuracy.)

4. Confirm the flatness of the measuring surface by using a flat crystal to closely adhere to the measured surface, and identify the flatness based on the number of interference fringes.

5.  Confirm the parallelism (four angles) between two measuring surfaces, clamp the parallel crystal with two measuring surfaces, and identify the parallelism based on the number of red interference fringes.

"One interference stripe=0.32 µ m"

The purpose of calibrating a micrometer is not only to ensure the accuracy of the measurement results, but also to avoid the use of inappropriate measuring tools. Due to the extremely high accuracy of the micrometer, if there are situations such as inaccurate base points and uneven rotation, please contact professional technicians. Do not disassemble it on your own to avoid being unable to restore it. For more details, please consult Nanjing Tuofeng Measurement Instrument Co., Ltd.