## Engineering Metrology and Measurement

#### About the Book

Metrology and Measurement play an important role in many engineering fields, especially in the production, inspection and quality control of physical products. Accurate measurement in real time is crucial for monitoring and controlling operations in many industries. This book deals with the basic concepts of measurement, including linear, angular and form measurement. It also explores in depth the measurement of force, strain, power, vibration, fluid flow and temperature. Recent advances such as laser metrology, computer-aided inspection and machine vision are also discussed. When coupled with extensive practical experiments, the book will help students gain a solid understanding of the main concepts of this fascinating subject.
Salient Features

• Comprehensive coverage of the syllabi pertaining to this subject of most Indian
• universities
• Incorporates end-of-chapter summaries, multiple choice questions and review
• questions
• Includes over 220 figures to complement the text
• Features a section on the use of statistical tools to ensure quality control

#### Contributors (Author(s), Editor(s), Translator(s), Illustrator(s) etc.)

K Duraivelu is Professor & Dean of Faculty of Engineering &Technology, Vadapalani Campus, SRM University, Chennai.

S Karthikeyan is Professor & Head of the Department of Mechanical Engineering, Vadapalani Campus, SRM University, Chennai.

#### Table of Contents

Foreword by Dr R Velraj
Foreword by Dr V Raghavan
Preface
Section I: Engineering Metrology
Chapter 1: Basic Concepts of Measurement
1.1 Introduction
1.2 Significance of Measurement
1.3 Precision and Accuracy of Measurement
1.3.1 Factors Affecting the Accuracy of the Measurement System
1.4 Reliability of Measurement
1.5 Methods of Measurement
1.6 Important Terms in Measurement
1.7 Standards of Measurement
1.8 Basic Units in the SI System
1.9 Classification of Standards
1.10 Errors in Measurement
1.10.1 Types of Errors in Measurement
1.10.2 Causes of Errors
Summary
Exercises
Multiple Choice Questions
Review Questions
Chapter 2: Linear Measurement
2.1 Introduction
2.2 Linear Measurement Instruments
2.3 Comparator
2.3.1 Classification of Comparators
2.3.2 Basic Working Principle of a Comparator
2.3.3 Mechanical Comparators
2.3.4 Optical Comparator
2.3.5 Pneumatic Comparator
2.3.6 Electrical Comparator
2.3.7 Electronic Comparator
2.4 Slip Gauges
2.5 Roller Gauges
2.6 Limit Gauges
2.7 Limits, Fits and Tolerances
2.7.1 Design of Limit Gauges
2.7.2 Types of Limit Gauges
Summary
Exercises
Multiple Choice Questions
Review Questions
Chapter 3: Angular Measurement
3.1 Introduction
3.2 Autocollimator
3.2.1 Principle of Autocollimation
3.2.2 Micro-Optic Autocollimator
3.3 Angle Dekkor
3.4 Angle Gauges
3.5 Alignment Telescope
3.6 Sine Bar
3.7 Sine Centre
3.7.1 Sine Table
3.7.2 Sources of Error in Sine Bar
3.8 Vernier Bevel Protractor
3.9 Vernier Clinometer
3.10 Measurement of V-Angle Using Rollers
3.11 Measurement of the Taper of a Bore Using Balls
3.12 Measurement of the External Circular Taper Using Rollers
Summary
Exercises
Multiple Choice Questions
Review Questions
Chapter 4: Form Measurement
4.1 Introduction
4.2 Classification of Pitch Errors
4.3 Measurement of Thread Parameters
4.3.1 Measurement of the Major Diameter of an External Thread
4.3.2 Measurement of the Minor Diameter of an External Thread
4.3.3 Measurement of the Effective Diameter of an External Thread (Two-Wire Method)
4.3.4 Measurement of the Effective Diameter of an External Thread (Three-Wire Method)
4.3.5 Measurement of the Diameter of an Internal Thread
4.3.6 Measurement of the Pitch of a Thread
4.3.7 Measurement of Thread Parameters Using Toolmaker’s Microscope
4.4 Measurement of Gear
4.5 Profile Projector
4.6 Testing the Involute Form – David Brown Tester
4.7 Parkinson Gear Tester
4.8 Gear Tooth Vernier Calipers
4.9 Radius Measurement
4.9.1 Radius of Curvature of any Job Having a Portion of a Circle
4.9.2 Radius of Curvature of a Blunt Corner of a Job
4.9.3 Radius of a Concave Surface (Cavity)
4.9.4 Measurement of Smaller Radius of Curvature
4.10 Surface Finish
4.10.1 Elements of Surface Texture
4.10.2 Measurement of Surface Finish
4.10.3 Assessment of Surface Roughness as per Indian Standards
4.11 Straightness Measurement
4.11.1 Spirit Level Method
4.11.2 Autocollimator Method
4.11.3 Straight Edge Method
4.11.4 Method of Comparison with the Surface of a Liquid
4.11.5 Beam Comparator
4.12 Flatness Measurement
4.12.1 Direct Comparison with the Surface Plate
4.12.2 Spirit Level Method
4.12.3 Autocollimator Method
4.12.4 Beam Comparator
4.12.5 Comparison with the Surface of a Liquid
4.12.6 NPL Flatness Interferometer Method
4.12.7 Liquid Interference Method
4.13 Testing of Roundness (Circularity)
4.13.1 V Block and Dial Gauge Method
4.13.2 Polar Graph Method
4.13.3 Rotating on Centres Method
4.13.4 Roundness Testing Machines
4.13.5 Cylindricity, Concentricity and Run-out
Summary
Exercises
Multiple Choice Questions
Review Questions
Chapter 5: Advances In Metrology
5.1 Introduction
5.2 Principle of Interference
5.2.1 Important Properties of Laser in Interferometry
5.3 Laser in Measurement of Small Dimensions
5.4 Laser Interferometer in Linear Measurement (Large Displacement)
5.5 Optical Flats in Laser Metrology
5.6 Precision Instruments Based on Laser
5.7 Laser Telemetric System
5.8 Angular Measurement
5.9 Coordinate Measuring Machines (CMM)
5.9.1 The Touch Trigger Probe (Renishaw Probe)
5.9.2 Types of CMM
5.9.3 Advantages and Disadvantages of CMM
5.10 Computer Numerical Controlled (CNC) CMM
5.11 Diffraction Gratings – Measuring System
5.11.1 Applications of Moire Fringes in Measurement
5.12 Laser Scanning Micrometer
5.13 Computer-Aided Inspection
5.14 Machine Vision and Image Processing
Summary
Exercises
Multiple Choice Questions
Review Questions
Section II: Engineering Measurement
Chapter 6: Measurement of Force, Strain and Pressure
6.1 Measurement of Force
6.1.1 Equal Arm Balance
6.1.2 Analytical Balance
6.1.3 Unequal Arm Balance
6.1.4 Multiple Lever Systems
6.1.5 Pendulum Force Measuring Scale
6.1.6 Elastic Force Meters
6.1.7 Proving Ring
6.1.8 Hydraulic Load Cell
6.1.9 Pneumatic Load Cell
6.2 Measurement of Strain
6.2.1 Metallic Resistance Strain Gauges
6.2.2 Circuitry for Strain Gauges
6.2.3 Temperature Compensation for Strain Gauges
6.2.4 Strain Gauge Rosettes
6.3 Measurement of Pressure
6.3.1 Static and Dynamic Pressure
6.3.2 Methods of Pressure Measurement
6.3.3 Manometers
6.3.4 Bourdon Tube Pressure Gauge
6.3.5 Bellows Pressure Gauge
6.3.6 Diaphragm Pressure Gauge
6.3.7 Low-Pressure Measurement
6.3.8 Thermal Conductivity Gauges
6.3.9 Ionisation Gauges
6.3.10 Knudsen Gauge
6.3.11 Pressure Cells
Summary
Exercises
Multiple Choice Questions
Review Questions
Chapter 7: Measurement of Torque and Power
7.1 Introduction
7.2 Mechanical Torsion Meter
7.3 Optical Torsion Meter
7.4 Electrical Torsion Meter
7.5 Strain Gauge Torsion Meter
7.6 Dynamometer – Hydraulic
7.7 Dynamometer – Mechanical
7.8 Dynamometer – Electrical
7.9 Transmission Dynamometer
Summary
Exercises
Multiple Choice Questions
Review Questions
Chapter 8: Measurement of Level, Vibration and Translation
8.1 Measurement of Level
8.2 Direct Methods
8.2.1 Hook Level Indicator
8.2.2 Sight Glass (Gauge Glass) Indicator
8.2.3 Float-Operated Level Indicator
8.3 Indirect Methods
8.3.1 Capacitive Liquid Level Sensor
8.3.2 Ultrasonic Fuel Level Meter
8.3.3 Magnetic Level Indicator
8.3.4 Cryogenic Fuel Level Indicator
8.3.5 Bubbler (Purge) Level Indicator
8.4 Measurement of Vibration
8.4.1 Laser Doppler Vibrometer (LDV)
8.4.2 Seismic Instruments (Vibrometers and Accelerometers)
8.5 Sound (Decibal) Meters
8.6 Measurement of Displacement
8.6.1 Linear Variable Differential Transformer
8.6.2 Resistance Potentiometer
8.7 Measurement of Speed
8.7.1 Mechanical Tachometer
8.7.2 Electrical Tachometer
8.7.3 DC Tachometer
8.7.4 AC Tachometer
8.7.5 Stroboscope
8.7.6 Pick-Up Tachometer
8.8 Measurement of the Speed of a Moving Object
Summary
Exercises
Multiple Choice Questions
Review Questions
Chapter 9: Measurement of Fluid Flow
9.1 Measurement of Flow
9.2 Obstruction Meters
9.2.1 Venturimeter
9.2.2 Orifice Meter
9.2.3 Flow Nozzle
9.2.4 Rotameter
9.3 Coriolis Flow Meter
9.4 Turbine Flow Meter
9.5 Electromagnetic Flow Meter
9.6 Ultrasonic Flow Meter
9.7 Pitot Static Tube
9.8 Hot-Wire Anemometer
9.9 Laser Doppler Anemometer
9.10 Flow Visualisation Methods
9.10.1 Dye Injection
9.10.2 Laser-Induced Fluorescence
9.10.3 Smoke Wire Visualisation
9.10.4 Hydrogen Bubble Visualisation
9.10.5 Shadowgraph and Schlieren Technique
Summary
Exercises
Multiple Choice Questions
Review Questions
Chapter 10: Measurement of Temperature
10.1 Introduction
10.2 Basics of Temperature
10.3 Temperature Scales
10.4 Methods of Temperature Measurement
10.5 Principles of Temperature Measurement
10.5.1 Expansion
10.5.2 Change of State
10.5.3 Electrical Method
10.6 Temperature Ranges
10.7 Thermocouples
10.8 Thermistors
10.9 Pressure Thermometers
10.10 Resistance Thermometers
10.11 Pyrometers
10.11.1 Total Radiation Pyrometers
10.11.2 Infrared Pyrometers
10.11.3 Optical Pyrometers
Summary
Exercises
Multiple Choice Questions
Review Questions
Section III: Quality Control
Chapter 11: Statistical Quality Control
11.1 Introduction
11.2 Quality Control and Quality Assurance
11.3 Causes of Variation
11.4 Control Chart and its Selection
11.5 Process Capability
11.6 Sampling Plans
11.6.1 Classification of Sampling Plans
11.7 OC Curve and AOQ Curve
11.8 Solved Problems
Summary
Exercises
Multiple Choice Questions
Review Questions
Appendix 1 Table of Constants for Control Charts for Variables
Appendix 2 Table of Standard Normal Probabilities
Index

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