QUALITY ASSURANCE MANUAL

Calibration of Outside Diamater MicrometersWritten By: Preston Gary

1PURPOSE

To define the procedure to be followed for the calibration of outside measuring micrometers.

2APPLICATION

This procedure shall be followed in any location where AIT Machine, LLC. conducts calibration of outside measuring micrometers that are to be used for quality control measurements.

3PROCEDURES

3.1 General ProceduresAny micrometer that cannot be repaired or adjusted by reference to this procedure shall be scrapped or permanently removed from service as a quality control measuring device.

3.2 Visual Inspection

Each micrometer shall be visually inspected to assure that:

a) It has not been damaged or has sustained excessive wear.

b) That division marks on the thimble and barrel are legible.

3.3Calibration

The readings of the micrometer shall be checked at the numerous intervals of the micrometer range as follows:

Calibration of each outside measuring micrometer shall proceed as follows:

a) Use Setting Pin and Block Standards according to the range of the micrometer. For example, multiple Setting Pin and Block Standards shall be used to calibrate/verify 0 1 O.D. & Blade Micrometers because we own numerous standards that fall within that range. Larger micrometers may only be checked at their low and high ranges only because the limited standard sizes we possess.

b) If the micrometer is found to be out of tolerance the barrel of the micrometer shall be rotated with an appropriate spanner wrench to bring the micrometer into tolerance.

c) If dirt, grime, or excessive lubricants exists the micrometer should be cleaned thoroughly prior to re-assembly in mineral solvent and coated with light oil.

4 NONCONFORMANCE

4.1 Excessive Wear or Damage

When excessive wear is detected during any calibration procedure the following action shall be taken:

a) Remove thimble and spindle and tighten the slotted adjusting nut enough to eliminate excess play in the mechanism.

b) Insure that all components are clean and free of foreign material before replacing the thimble and spindle.

c) Re-calibrate micrometer per above procedure.

If damage is such that the micrometer cannot be repaired in house it should be sent to an approved vendor for repair and re-calibrated before its use as a quality control instrument or marked with a red tag, segregated and taken out of service.

5 DOCUMENTATION

5.1Calibration Record

After the micrometer has been calibrated, the following should be completed:

a) Any old calibration stickers should be removed and replaced with a new one showing the date of calibration, the next calibration due date, the serial number of the MTE, and if space allows, the range of the MTE.

b) All calibration logs within the AIT Machine database and other documentation should be completed and appropriately filed.

c) If any micrometer is found, before calibration, to be out of calibration more than .001, the Quality Manager shall be notified.

Approved by: Controlled Document AITM-042, Rev. 1 5/17/2013