ENGINEERING METROLOGY QAS 0312 GMI | Production Technology

ENGINEERING METROLOGY Course Objective Students should be able to: Explain the basic concepts of testing, measuring and gauging procedures used in engineering. Perform inspection of linear and angular measurement by using various types of measuring instruments and gauging methods. GMI | Production Technology

ENGINEERING METROLOGY Main Topics Fundamentals of Metrology Basic Inspection and Procedures Measurement Errors Vernier Caliper Micrometer Mechanical Dial Indicator Gauge Blocks Surface Plate Inspection Instruments for Testing Angles Gauges Profile Projector Surface Roughness Measurement Measurement of Threads GMI | Production Technology

ENGINEERING METROLOGY Assessment: CMM – 40% Metrology – 50% KQ – 10% PBL 1 : 10% PBL 2 & Practical : 25% Test : 15% GMI | Production Technology

FUNDAMENTALS OF METROLOGY CHAPTER 1 GMI | Production Technology

FUNDAMENTALS OF METROLOGY Learning Objectives Define the term metrology Differentiate between accuracy and precision Explain the needs and functions of inspection List the objectives of metrology Identify SI units and dimensions Perform conversion of SI units GMI | Production Technology

FUNDAMENTALS OF METROLOGY What is Metrology? Science of measurement. Concerns in correctness of measurement Precision Accuracy Methods and techniques of measurement based on agreed units and standards GMI | Production Technology

Precision vs Accuracy Inaccurate and imprecise (unrepeatable) Stone age man missed the bull's-eye and the 3 attempts were not near each other. Precise but inaccurate Robin Hood's Merry Man missed the bull's-eye but the 3 attempts were near each other.

Precision vs Accuracy (cont) Accurate but imprecise American Indian's 3 attempts are near the bull's-eye, but were not near each other. Accurate and precise Olympic archer hits the bull's-eye 3 times!

FUNDAMENTALS OF METROLOGY Why is Metrology important? Standardization in trade Eliminating technical barriers in trade, manufacturing industry, construction etc etc. Promoting awareness to Quality Assurance What is Inspection? Formal or Official examination of products with the use of accurate (calibrated) measuring instruments GMI | Production Technology

manufacturing department Needs and Functions of Inspection To achieve interchangeability To determine good or bad parts To support the manufacturing department To improve and develop precision measuring instruments German Malaysian Institute

FUNDAMENTALS OF METROLOGY To determine good and bad parts To determine the conformance of products to specifications or requirements – important in assisting manufacturing process and assuring of quality. In industry, inspection is used for selection of products whether it can be ‘accepted’ or ‘rejected’ To maintain the product quality – meet customer satisfaction index GMI | Production Technology

FUNDAMENTALS OF METROLOGY To achieve Interchangeability Interchangeability – products should be able to fit and mate if chosen randomly from different manufacturers Examples: Screws and threads, nuts and bolts, pipes and pressure vessels, pnuematic and hydraulics fittings/valves, etc. Can be achieved by means of measuring and gauging Calipers, micrometers, thickness gauge, radius gauge etc Plug gauge, pin gauge, ring gauge etc GMI | Production Technology

FUNDAMENTALS OF METROLOGY To improve and develop precision measuring instruments Due to demands of high accuracy and precision works or products Promote spirit of competition between manufacturers to produce high quality precision parts GMI | Production Technology

FUNDAMENTALS OF METROLOGY To support the manufacturing department Functions of inspection in manufacturing industries Conformity of product’s appearance and functions Conformity of product’s dimensional specifications Conformity of product’s performance Providing data for product’s improvement analysis Production process Manpower skills Material analysis Machines accuracy and maintainance GMI | Production Technology

OBJECTIVES OF METROLOGY Ensure products designed – within process spec & measuring instrument capabilities. (products) Determine process capabilities. (processes) Determine the measuring instrument capabilities. (instruments) Reduce the cost of rejects & rework. (products) Minimize the cost of inspection. (products) Maintenance of the accuracy of measurement. (instruments) GMI | Production Technology

Principles of Metrology Fundamentals Units and standards International System of Units (SI) - established in 1960 - by CGPM (General Conference of Weight and Measures) - e.g : Force Newton N (kgm/s2) advantages of coherency of SI units. same system & units of measurement regardless of industries minimum of conversion factors

FUNDAMENTALS OF METROLOGY Principles of Metrology Fundamentals Units and Standards Language of measurement and must be constant worldwide SI base units: Length : Meter (m) Mass : Kilograms (kg) Time : second (s) Current : Ampere (A) Thermo. Temp : Kelvin (K) Amount of subs. : Mole (mol) Luminous intensity : Candela (cd) GMI | Production Technology

FUNDAMENTALS OF METROLOGY Principles of Metrology SI Prefixes Prefixes Symbol Multiplier peta P 1015 deci d 10-1 tera T 1012 centi c 10-2 giga G 109 mili m 10-3 mega M 106 micro µ 10-6 kilo k 103 nano n 10-9 hecta h 102 pico p 10-12 deka da 101 femto f 10-15 GMI | Production Technology

FUNDAMENTALS OF METROLOGY Principles of Metrology SI derived units: Area : square meter (m2) Volume : cubic meter (m3) Velocity : meter per second (m/s) Acceleration : meter per square sec. (m/s2) Force : Newton (N) Luminance : candela per square meter (cd/m2) GMI | Production Technology

FUNDAMENTALS OF METROLOGY Convert the following unit:  a) 0.88dm to mm: b) 200µm to Mm : c) 15mg/Gm³ to kg/cm³ : GMI | Production Technology