JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD

Overview

Course overview: To provide a basic understanding of the wide range of activities encompassed by personnel working in standards and calibration laboratories. It covers the measurement process, types and correct use of measurement and test equipment, and measurement standards. It provides an opportunity for students to learn about measurement uncertainty and risk analysis. The course includes the procedures necessary to set up and to have knowledge on calibration. At the end of this subject the student is expected: It is expected to enforce, validate and verify predefined standards for traceability, accuracy, reliability, and precision. All of these are factors that would affect the validity of measurement. Although these standards vary widely, these are mandated by the government, the agencies, and some treaties. Consequently, these standards are verified and tested against a recognized quality system in calibration laboratories

Course Objectives:

• 1. To be familiar with the different instruments those are available for linear, angular, roundness and roughness measurements.
• 2. To be able to select and use the appropriate measuring instrument according to a specific requirement (in terms of accuracy, etc.)
• 3. It is the aim of this course to provide students with practical skills associated with each of these areas. Metrology activities include precision measurement of component features, form and geometry utilizing specialized measuring instruments and equipment.
• 4. Effectively designing product processing methods.
• 5. To enhance the ability of students to apply scientific methods of protection

Course Outcomes:

• 1. Graduates will demonstrate basic knowledge in mathematics, science and engineering
• 2. Graduates will demonstrate an understanding of their professional and ethical responsibilities
• 3. Graduates will demonstrate the ability to function on engineering and science laboratory teams, as well as on multidisciplinary design teams
• 4. Graduates will demonstrate the ability to identify, formulate and solve mechanical engineering problems
• 5. Graduates will have the confidence to apply engineering solutions in global and societal contexts. Graduates should be capable of self-education and clearly understand the value of life-long learning. Graduates will have ability to communicate in written, oral and graphical forms.

UNIT - I

Systems of limits and fits: Introduction, normal size, tolerance limits, deviations, allowance, fits and their types - unilateral and bilateral tolerance system, hole and shaft basis systems -

R16 B.TECH MSNT.

interchangeability and selective assembly. Indian standard Institution system - British standard system, International Standard system for plain ad screwed work.

UNIT - II

Linear Measurement: Length standard, line and end standard, slip gauges - calibration of the slip gauges, Dial indicator, micrometers. Measurement of Angles and Tapers: Different methods - Bevel protractor - angle slip gauges - spirit levels - sine bar - Sine plate, rollers and spheres used to determine the tapers. Limit Gauges: Taylor’s principle - Design of go and No go gauges, plug ring, snap, gap, taper, profile and position gauges.

UNIT - III

Optical Measuring Instruments: Tool maker's microscope and its uses - collimators, optical projector - optical flats and their uses, interferometer. Flat Surface Measurement: Measurement of flat surfaces - instruments used - straight edges - surface plates - optical flat and auto collimator.

UNIT - IV

Surface Roughness Measurement : Differences between surface roughness and surface waviness-Numerical assessment of surface finish - CLA, R, R.M.S Values - Rz values, Rz value, Methods of measurement of surface finish-profilograph. Talysurf, ISI symbols for indication of surface finish.

UNIT - V

Screw Thread Measurement: Element of measurement - errors in screw threads - measurement of effective diameter, angle of thread and thread pitch, profile thread gauges. Measurement Through Comparators: Comparators - Mechanical, Electrical and Electronic Comparators, pneumatic comparators and their uses in mass production. MACHINE TOOL Alignment Tests: Requirements of Machine Tool Alignment Tests, Alignment tests on lathe, milling, drilling machine tools.. Preparation of acceptance charts. Gear Measurement: Gear measuring instruments, Gear tooth profile measurement. Measurement of diameter, pitch pressure angle and tooth thickness. Coordinate Measuring Machines: Types of CMM, Role of CMM, and Applications of CMM.

TEXT BOOKS

• 1. Engineering Metrology / I C Gupta./ Danpath Rai
• 2. Engineering Metrology / R.K. Jain / Khanna Publishers

REFERENCE BOOKS

• 1. BIS standards on Limits & Fits, Surface Finish, Machine Tool Alignment etc.
• 2. Principles of Engineering Metrology, Rajendra
• 3. Metrology & Measurement, Bewoor, Anand K R16 B.TECH MSNT.