Gauge Calibration and Testing

1. Which of the following is true for the calibration of instruments?

In casting and fabrication shops the measurements made are of more precise nature as compared to those made in machine shop and tool room

Periodical calibration is made for optical measuring instruments

There is no need of periodic calibration in universal microscope

Preventive maintenance is not necessary for optical measuring instruments

2. What is the maximum permissible error for class I micrometers?

0.016 mm

0.002 mm

0.008 mm

0.004 mm

3. What is the relation between variation due to observation, manufacturing process and measuring process of a product?

σ_observation = σ_process / σ_measurement

σ_observation = σ_process - σ_measurement

σ_observation = σ_process + σ_measurement

σ_observation = σ_process * σ_measurement

4. What is the least count of dial indicators which can be calibrated using passmeter?

0.05 mm

0.07 mm

0.03 mm

0.01 mm

5. Which of the following is used to check change in ocular lines position due to column rotation in universal micrometer?

Dial indicator

Slip gauges

Control shaft

Universal microscope

6. What is the permissible error in the perpendicular motion of ocular microscope column w.r.t. The work stage over 100 mm movements?

0.07 mm

0.06 mm

0.05 mm

0.04 mm

7. What is the permissible error in straight movement of longitudinal and transverse table in horizontal plane?

0.005 mm

0.004 mm

0.003 mm

0.002 mm

8. What is the maximum permissible error in wear of centres?

0.03 mm

0.01 mm

0.02 mm

0.04 mm

9. What is the least count of clinometer which is used to check reading of column rotation used for setting of helix angles in universal micrometer?

4’

2’

3’

1’

10. Which of the following is true for checking the Relative perpendicular motion of the longitudinal and transverse carriage?

Precision square of class I or 0 is used

Maximum error in precision error is of ± 10″ in squareness

The permissible error allowed is 0.005 mm in 2500 mm length.

This is checked using a slip gauges