Dial Indicator

1. Prepared by,
Mr. S. B. Kamble
Department of Mechanical Engineering
Sharad Institute of Technology, College of Engineering, Yadrav
Subject – Metrology and Quality Control

3. Classification
1. Mechanical comparators
• Dial Indicator
• Reed Type comparator
• Sigma Comparator
• Johansson Mikrokator
2. Mechanical-Optical Comparators
• Optical Lever
• Zeiss Optimeter
• Zeiss Ultra Optimeter
• Zeiss Optotest Comparators
3. Electrical and Electronics Comparators
4. Pneumatic Comparators
5. Fluid Displacement Comparators
6. Projection Comparators
10. High Sensitive Calibration
Comparators
• Brookes Level Comparators
• Eden-Rolt Millionth Comparator
7. Multi check Comparators
8. Automatic Gauging
9. Electro Mechanical Comparators

4. Classification of Dial Indicator
Dial Gauge
Circular Dial
Dial Micrometers
Back Plunger type
Sector Dials
Lever Movements
Special devices
Gear
Movements

5. Dial Indicator
Image Source - Internet

6. Working Mechanism of Dial indicators
Image Source - Internet

7. Dial Indicator Parts
Least count
100 lines reading equal to
1 mm
Least count = 1 rotation on
main scale/No. of division
moved on dial scale
Least count =1/100
Least count =0.01mm
Image Source - Internet

8. Lever type Indicator
Image Source - Internet

9. Advantages of Dial Indicator
• Ease of reading a dial indicator
• It involves amplification by gear trains which permits a sturdy construction and is less
sensitive to shocks and vibrations than other systems of design.
• Long measuring range is possible
• These usually permits a reasonable amount of over-travel without injuring the mechanism
• Dial form of display with several turns of the hand, permits extended indicating range with a
high resolution
• Initial as well as maintenance cost are low

10. Disadvantages of Dial Indicator
• Wear results in backlash and lagging response.
• Dial gauges are not considered suitable for extended measuring range for precision
applications.
• The clearance of the measuring spindle in its guides can result in positional variations of the
rack in relation to the meshing pinion.
• Play in pivot bearing due to initial inaccuracies or wear effects the precise meshing of the
gear teeth causing measuring errors.

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