Q1: What are Dial Instruments?
Ans: Dial instruments are precision measuring instruments that show readings on a circular dial with a pointer instead of a digital display.
Q2: Name some Dial Instruments.
Ans: Some dial instruments are:
- ➔ Dial Caliper
- ➔ Dial Thickness Gauge
- ➔ Dial Bore Gauge
- ➔ Dial Indicator
Q3: What is a Dial Caliper?
Ans: A dial caliper is a precision measuring instrument used to measure internal, external, and depth dimensions with a dial indicator.
Q4: What is the working principle of a Dial Caliper?
Ans: It works on the rack and pinion mechanism.
The linear motion of the slider is converted into rotary motion of the dial pointer.
The pointer shows the measurement on the dial.
Q5: What is the Least Count of a Dial Caliper?
Ans: The least count of a dial caliper is usually 0.02 mm.
Q6: What is the size of a Dial Caliper?
Ans: Dial calipers are commonly available in sizes like:
Q7: Name the parts of a Dial Caliper.
Ans: Parts are:
- ➔ Main scale
- ➔ Sliding jaw
- ➔ Fixed jaw
- ➔ Dial indicator
- ➔ Depth rod
Q8: State the uses of a Dial Caliper.
Ans: Uses are:
- ➔ Measuring external dimensions
- ➔ Measuring internal dimensions
- ➔ Measuring depth
- ➔ Quick inspection work
Q9: State the precautionary measure while using a Dial Caliper.
Ans: Precautions are:
- ➔ Handle carefully to avoid damage
- ➔ Do not apply excessive force
- ➔ Keep clean and dry
- ➔ Check zero error before use
Q10: How do you read a Dial Caliper?
Ans: Read the main scale first.
Then note the dial reading.
Add both readings to get the final measurement.
Q11: What is a Dial Thickness Gauge?
Ans: A dial thickness gauge is a measuring instrument used to measure the thickness of thin materials using a dial indicator.
Q12: What is the working principle of a Dial Thickness Gauge?
Ans: It works on the spring-loaded mechanism.
The movement of the contact point is converted into dial movement.
The reading is shown on the dial.
Q13: What is the Least Count of a Dial Thickness Gauge?
Ans: The least count is usually 0.01 mm to 0.02 mm.
Q14: What is the size of a Dial Thickness Gauge?
Ans: Dial thickness gauges are available in different ranges such as:
Q15: Name the parts of a Dial Thickness Gauge.
Ans: Parts are:
- ➔ Anvil
- ➔ Spindle
- ➔ Dial indicator
- ➔ Frame
- ➔ Spring mechanism
Q16: State the uses of a Dial Thickness Gauge.
Ans: Uses are:
- ➔ Measuring sheet thickness
- ➔ Checking rubber and plastic sheets
- ➔ Quality inspection
Q17: State the precautionary measure while using a Dial Thickness Gauge.
Ans: Precautions are:
- ➔ Do not apply extra pressure
- ➔ Keep measuring faces clean
- ➔ Handle gently
Q18: How do you read a Dial Thickness Gauge?
Ans: Place the material between the anvils.
The spindle moves and dial pointer shows reading.
Direct reading is taken from the dial.
Q19: What is a Dial Bore or Hole Gauge?
Ans: A dial bore gauge is a precision instrument used to measure the internal diameter of holes.
Q20: What is the working principle of a Dial Bore or Hole Gauge?
Ans: It works on the comparative measurement principle.
The contact points expand inside the bore.
Movement is transferred to the dial indicator.
Q21: What is the Least Count of a Dial Bore or Hole Gauge?
Ans: The least count is usually 0.01 mm.
Q22: What is the size of a Dial Bore or Hole Gauge?
Ans: Dial bore gauges are available in ranges such as:
- ➔ 10–30 mm
- ➔ 30–50 mm
- ➔ 50–160 mm
Q23: Name the parts of a Dial Bore or Hole Gauge.
Ans: Parts are:
- ➔ Dial indicator
- ➔ Measuring head
- ➔ Contact points
- ➔ Extension rods
- ➔ Handle
Q24: State the uses of a Dial Bore or Hole Gauge.
Ans: Uses are:
- ➔ Measuring internal diameter of holes
- ➔ Checking cylinder bores
- ➔ Inspection work
Q25: State the precautionary measure while using a Dial Bore or Hole Gauge.
Ans: Precautions are:
- ➔ Set zero correctly before use
- ➔ Handle carefully
- ➔ Avoid damage to contact points
Q26: How do you read a Dial Bore or Hole Gauge?
Ans: Insert the gauge into the bore.
Move it slightly to find maximum reading.
Note the dial reading and compare with standard size.
