A micrometer is an engineering tool that is used for measuring the outer diameter of the object. It is used for accurate measurement. This instrument used to obtain a very small measurement of the object. The least count of the Micrometer is 0.01 in MM and 0.001 in CM. This instrument is used various types of a dimension such as a Diameter, Length, and thickness.
The frame part of the micrometer is half arc-shaped which has one side attached anvil and another side is spindle. The main function is a frame to hold the anvil which is mounted on one side.
The measuring face has two main parts Anvil and Spindle which have to give an accurate reading with the help of sleeve.
The main function of the index line is to divide the reading scale into two parts. The upper part of the index line gives the simple reading for example 2,3,5,6 and the bottom scale of the index line is to give the point reading like 0.1,0.3,3.7 etc.
The sleeve scale is a measuring scale in which the measurement line is vertical to the axis and projected reading line and index line.
The function of lock nut is to lock the reading by means of a screw thread on it. It locks the sleeve scale.
The thimble scale is a measuring scale which has a horizontal measuring line.
The function of the thimble is only to rotate the thimble scale.
The function of the ratchet speeder has adjusted the spindle. When rotating the ratchet speeder it gives the actual position of the spindle.
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