MEASURING INSTRUMENTS : MICROMETER



                             MICROMETER 
                              This measuring instrument is used to measure the accurate readings of object.It is also known as micrometer screw gauge. In machine shop and mechanical instruments dimensions are measured by micrometer. The parts of micrometer as,

        The picture of Micrometer shown below,

 PIC.01
        


Parts of the Micrometer,

1.  Frame (main body)
2.  Anvil
3.  Sleeve
4.  Thimble
5.  Lock
6.  Screw
        Basically micrometer used for precision measurement, used for extremely small dimensions of the object. The dimensions of object which unable to measure by Vernier caliper is measured by micrometer.
   Micrometer consist of two different scales.By rotation of screw the dimensions are measured in micrometer. Two scales as main scale & secondary scale, the secondary scale mentioned on thimble, the readings of secondary scale is measured by distance moved by thimble, the thimble is divided  into 50 equal parts.
            It is required to calibrate the micrometer before use to avoid deviations while measurement.
           As per requirements different ranges and different sizes of micrometer available in market.
   Different types of micrometer consisting outside micrometer,inside micrometer,vernier type micrometer,rod type micrometer,depth micrometer etc.
   The advantages and disadvantages of micrometer shown below,

  Advantages

1) integrated readings scales is provided om micrometer for easy measurement.

2) Micrometer provide very accurate measurement.

3) Some special type of micrometer available in market for particular type of work.

4) Accuracy 0.001 mm.

5) Micrometers are very durable.

   Disdvantages

              1) Limited range - Most micrometers have measure only upto 25 mm.(one micrometer cannot measures all sizes).
            
          2) Required to read and measure the proper reading on scale.

         3) Larger micrometers difficult to use and expensive.

         4) Need to stored in clean environment to protect from accidental damage.

         5) The are need to kept in calibration, frequent checking required against standards.

x
Previous
Next Post »