For cleaning measuring tools such as thread rings, thread gauges, bore gauges, adjustment rings, etc. before use, storage or calibration, you should wipe off any debris with a cloth or brush. You should generally avoid blowing clean measuring tools with compressed air.
Once you have wiped off any debris, you can proceed according to the following

Method 1

Pour lukewarm to warm water in a spray bottle and add PLANOCLEAN so that you obtain 1.5-2% concentration.

a) spray the measuring tools with the solution so that the solution easily runs off the measuring tool
b) leave it to "rest" on the cloth for up to 5 minutes in order for the agent to work and loosen the dirt.
c) rinse the measuring tool with hot water and if necessary use a brush or dish brush to remove any remaining dirt. Repeat procedure a) – c) if dirt remains.
d) wipe the measuring tool dry
e) after completion of the cleaning, oil with thin oil

NOTE! - if the measurement tool is to be calibrated then oiling should be avoided until the calibration has been performed. In order not to risk corrosion damage during the tempering period, the measuring tool should be stored in a place with dry air

Method 2

Ultrasound washing gives a very good result,
a) concentration 1.5-2%
b) heat 50º-55C
c) 3-5minutes
d) allow to dry in the net basket after rinsing in lukewarm water
e) Oil with thin oil to counteract corrosion

NOTE! - if the measurement tool is to be calibrated then oiling should be avoided until the calibration has been performed. In order not to risk corrosion damage during the tempering period, the measuring tool should be stored in a room with dry air