What is a micrometer? How many types of micrometers are there? And how do you use a micrometer?

A micrometer is a highly accurate measuring tool. And can measure in both millimeters (Metric) and inch (Imperial) units, giving measurements up to 0.001 mm in Metric measurements and 0.0001 inches in imperial measurements, which are mostly used with work related to engineering. that require high precision

Micrometers offer higher measurement accuracy than other measuring instruments such as vernier calipers or dial calipers, depending on how detailed the application is. which micrometer Used to measure the width, length, thickness, level difference, depth or diameter of an object. And when referring to the word micromotor as a whole, it means outside micrometer as illustrated below

Micrometer Components

  • Frame: C-shaped, serves to hold components together. There are various shapes and sizes. This allows the micrometer to be used as needed. The brand is generally indicated on the frame, the measuring range and the resolution value are indicated.
  • Support shaft (Anvil): looks like a solid round shaft, attached to the frame. Used to support the workpiece while measuring. Made from cast iron, strong and durable.
  • Spindle (Spindle): looks like a round shaft with a support axis. can move in-out to measure the size of the workpiece
  • Spindle Lock: Used to lock the measuring axis from moving. for accurate readings Some micrometers are knotted. and some models are small stems Can be rocked to lock or unlock.
  • Measuring sleeve (Sleeve): looks like a cylindrical rod. There is a main scale along the entire length. and has a long horizontal line called the reference line (Index Line)
  • Thimble : It looks like a cylindrical casing worn on the scale rod. Serves to rotate the measuring axis toward the workpiece. There is a scale around to read the detailed value.
  • Ratchet knob: located at the end of the micrometer's handle. Acts as a built-in torque wrench (Torque Wrench) to limit the torque, prevent the spindle from turning too tight or too loose.

Micrometer how to use?

Clean the contacts of both the anvil and spindle for best accuracy. Then turn the thimble casing clockwise. so that the measuring axis moves toward the workpiece until it almost touches the workpiece Then rotate the ratchet head clockwise to hear a loud sound about 2-3 times to limit the torque and prevent the spindle from turning too tight or too loose. which the resolution Micrometers have two levels of resolution.

Micrometer with a high resolution of 0.01 mm has 2 values.

  • 1. Sleeve scale 7 mm
  • 2. Thimble scale 0.37 mm (2 decimal places)
  • The value obtained is 7.37 mm.

Note The value on the thimble scale 0.37 is read at the position where the scale sleeve is in line with the level of the thimble.The thimble scale can be read directly to 0.1mm as shown above.

Micrometer with a resolution of 0.001 mm has 3 values.
  • 1. Sleeve scale 6 mm
  • 2. Thimble scale 0.21 mm (2 decimal places)
  • 3. Vernier scale 0.003 mm (3 decimal places)
  • The value obtained is 6.213 mm.

Note The value on the Thimble scale 0.21 is read where the scale line is between the two lines ( 21 and 22 ). In this case select the scale closest to the line and the value on the Vernier scale 0.003 mm corresponds to either of the grip lines. the most

How many types of micrometers are there?

There are three types of micrometers commonly used.

Outside Micrometer
More commonly used than other types, it is used to measure the width, length and outer thickness of shafts, blocks, spherical cables, wires, spherical objects, etc.

Inside Micrometer
Used to measure the width of various gaps such as inner diameter, circle hole, opening hole.

Depth Micrometer
Used to measure the depth of workpieces that are pits, potholes or channels.