Height and depth gauge linear metrology.pdf

Height gauges may also be used to measure the height of an object by using the underside of the scriber as the datum. The datum may be permanently fixed or the height gauge may have provision to adjust the scale, this is done by sliding the scale vertically along the body of the height gauge by turning a fine feed screw at the top of the gauge; then with the scriber set to the same level as the base, the scale can be matched to it. This adjustment allows different scribers or probes to be used, as well as adjusting for any errors in a damaged or resharpened probe.

1. LINEAR METROLOGY -
VERNIER HEIGHT GAUGE,
VERNIER DEPTH GAUGE
SUBMITTED TO : DR. VINAY SHARMA
Group no. : 02
50-50 contribution
NAME: AVINASH KISHORE SINGH
ROLL NO: BTECH/10453/21
Contribution : Vernier height gauge.
NAME: SHUBHAM KUMAR
ROLL NO: BTECH/10452/21
Contribution: Vernier depth gauge.

2. Introduction to Linear
Metrology
Linear metrology refers to the measurement of length, straightness,
flatness, and parallelism. It involves precise tools and techniques to ensure
accurate measurements in various industrial and scientific applications.
Precise measurements are critical for quality control and manufacturing
processes.

3. Vernier Height Gauge
A vernier height gauge is a specialized measuring instrument designed for taking precise height
measurements.
It offers significant advantages over a standard ruler in terms of accuracy and functionality.
why a vernier height gauge is preferred over a normal
scale for measuring height ?
Accuracy:
Normal Scale: Limited to the smallest division marked on the scale. For instance, a ruler with millimeter markings can only measure
down to 1 millimeter.
Vernier Height Gauge: The vernier scale allows readings to a fraction of the smallest division on the main scale. This significantly
increases the precision of measurements, often reaching up to 0.02 millimeters.
Suitability for Height Measurements:
Normal Scale: Can be cumbersome to use for height measurements, especially for objects with irregular shapes. Holding the scale
vertically and ensuring proper alignment can be challenging.
Vernier Height Gauge: Designed specifically for height measurements. The stable base and sliding jaw allow for accurate
measurement of the object's height from a fixed reference point.

4. The key components of a vernier height gauge work together to deliver precise height
measurements. Here's a breakdown of each part:
1.Base:
◦This is the foundation of the gauge, typically a rectangular block made of
sturdy metal with a finely ground and polished surface.
◦It ensures stability and provides a flat reference plane for the gauge to stand
upright.
2.Main Scale (Beam):
◦A long, vertical bar attached to the base.
◦It has a precisely etched scale, usually marked in millimeters (metric) or inches
(imperial).
◦This scale serves as the primary reference for measurement readings.
3.Vernier Scale (Slider):
◦This is the key component that enables the vernier height gauge's high
accuracy.
◦It's a smaller secondary scale that slides up and down along the main scale.
◦The vernier scale has its own set of graduations that are slightly closer
together compared to the main scale.
◦This slight difference allows for reading fractions of the smallest division on the
main scale.
4.Measuring Jaw:
◦This moveable jaw slides vertically along the main scale and vernier scale
assembly.
◦One end of the jaw has a flat surface that comes into contact with the top of
the object being measured.
◦The jaw often has a hole or slot to accommodate scribers or other attachments
for specialized tasks.

5. 1.Fine Adjustment Screw:
◦This screw is located near the measuring jaw and allows for precise control
over its position.
◦By turning the fine adjustment screw, you can make minute adjustments to
the jaw's height, ensuring an accurate measurement.
2.Clamp:
◦This is a mechanism that locks the vernier scale in place once the desired
measurement is obtained.
◦This prevents the vernier scale from accidentally moving, ensuring the
reading remains accurate.
In addition to these core components, some vernier height gauges may include
additional features like:
•Scriber: A small pointed tool that can be attached to the measuring jaw for
marking lines on a workpiece.
•Level: A small spirit level built into the base to ensure the gauge is perfectly
vertical during measurement.

6. Types of Vernier Height Gauge
Electronic Height GaugesDigital Counter Height Gauges Dial Height Gauge

7. CALIBRATION OF VERNIER
HEIGHT GAUGE
: Measuring instruments in usage will acquire certain errors
due to wear and tear. So every instrument should be checked
periodically to find out the errors and assess the accuracy.
Comparing the reading of the instrument with a standard
reference does this. This type of inspection is known as
calibration. Depending on the type of instrument the standard
reference is selected, against which the error of the
instrument is evaluated.

9. How to use the Height gauge.
1.The base of the height gauge is first wiped clean and placed on a flat surface such
as a surface plate and is checked for error, by observing that zero of the vernier
coincides with the zero of the main scale when the measuring pointer just touches the
reference surface.
2.The workpiece is then placed on the surface plate and the slider is moved with the
help of slider clamping screw and the measuring jaw is placed on the surface of the
specimen, so that it just touches the surface of the workpiece whose height is to be
measured. Employ the same precautions as in vernier calliper experiment to ensure
application of correct measuring force.
3.Now the measuring jaw is firmly clamped.
4. Read the measurements as below.
Main scale reading = A b.
Vernier scale reading ×least count = B
Final reading = A+B
5. Take the reading at a number of positions (minimum 10 ) and tabulate them. Before taking
any reading slide out the measuring tip or pointer from the surface of the work piece and slide
block to the same point to ensure application of correct measuring force.
6. Find mean of the reading, mean = X = (X1+X2+………Xn)/n.

10. Introduction to Depth
Gauge
A depth gauge is a precision measurement tool used to measure the depth
of holes, grooves, or recesses. It consists of a base, a measuring scale, and
a depth probe. This tool is essential for applications requiring accurate depth
measurements, such as in machining, carpentry, and metalworking.

11. Components and features of depth gauge
Precision Measurement
Allows for accurate and precise
depth measurements with clear
markings.
Durable Design
Constructed with robust
materials for longevity and
resistance to wear.
Versatility
Capable of measuring depths
across different types of
surfaces and materials.

12. How to use depth gauge for precise
depth measurements
Calibrating the Gauge
Ensure the depth gauge is properly calibrated before taking measurements.
Placing the Gauge
Position the depth gauge carefully on the surface to be measured.
Reading the Depth
Read the measurement displayed on the depth gauge with precision.

13. Advantages and limitations of depth gauge
•Advantages: Provides precise measurement of depth for small objects, versatile for various
materials, and easy to read scale for accurate results.
•Limitations: Limited to specific depth ranges, requires proper calibration, and may be affected by
debris or contaminants.

14. Conclusion and Key Takeaways
Precision in Measurement
Both the Vernier height gauge and depth
gauge are essential tools for achieving
accurate measurements in engineering and
manufacturing.
Application in Various Industries
These metrology instruments are used in a
wide range of industries, including
automotive, aerospace, and precision
machining.
Importance of Proper Usage
Correct training and usage of these
instruments are crucial for maintaining quality
standards and ensuring safety in industrial
processes.
Continuous Advancements
As technology advances, the instruments
continue to evolve, offering enhanced
precision and efficiency for measuring tasks.

15. THANK YOU