Dial Indicator - Introduction, Different Parts

Dial Indicator

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

2. Dial Indicator

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.

11. 11