Answer:
Step-by-step explanation:
When using a 0-25 mm outside micrometer, the following checks should be carried out each time to ensure accurate measurements:
Cleanliness: Before using the micrometer, ensure that both the measuring surfaces (anvil and spindle) are clean and free from any debris or contaminants. This can be done by wiping the surfaces with a clean, lint-free cloth.
Zero Adjustment: Check and adjust the zero position of the micrometer. Close the micrometer fully so that the anvil and spindle are in contact, then rotate the thimble or ratchet until the zero on the sleeve scale aligns with the datum line. This step ensures that the micrometer is properly calibrated and ready for accurate measurements.
Anvil and Spindle Alignment: Verify that the anvil and spindle are aligned properly when in contact. Gently close the micrometer and observe if the anvil and spindle make even and parallel contact along their entire measuring surfaces. If they do not align correctly, it may indicate a need for calibration or maintenance.
Measurement Confirmation: To ensure accurate measurements, compare the micrometer readings with a known standard or calibrated reference gauge block. Take a few measurements using the micrometer and compare the results with the known standard. This step helps identify any discrepancies or measurement errors that may require adjustment or calibration.
Measurement Technique: When using the micrometer, employ proper measurement techniques. Apply consistent and gentle pressure when closing the micrometer to ensure accurate readings. Avoid excessive force or overtightening, as it may lead to inaccurate measurements or damage the micrometer.
By following these checks each time the micrometer is used, you can help ensure reliable and accurate measurements. It's also important to periodically calibrate the micrometer using traceable reference standards to maintain its accuracy over time.