Lecture 1: Measurement, Inspection and Testing
19 August 2013 12:27 PM
• Safety First
• Introduction to Manufacturing Processes
• The Three Principles of Measurements
• Measurementand Gauging Tools
• DVD on Measurementand Gauging
• Manufacturing: Economicterm for making goods and services available to satisfy human
• Implies creating value by applying useful mental and physical labour. It is a value adding
• Critical to country's welfare and standard of living as this is determined by the goods and
services that are available to its people.
• Represents 20-30%of the value of goods and services produced in industrialised countries
• A complexactivity involving people with a broad range of disciplines and skills as well as a
wide variety of machinery, equipment and tools with various levels of automation,including
computer,robots, and material handling equipment.
• The aim is the reduce the time to market while maintaining better quality and higher
productivity at the lowest possible cost.
• The overall objectiveis to supply a product that maximisescustomer satisfaction at minimum
Basic Manufacturing Processes
• Machining (Metal removal)Processes:Turning, milling, drilling, grinding, sawing, broaching
• Casting, Foundry or Moulding Processes:Sand Casting, Investment Casting and die casting
• Forming and MetalworkingProcesses:Hot Working (Rolling, forging, extrusion and drawing),
Cold Working (bending, shearing and sheet metal forming)
• Joining and Assembly: Welding, soldering and brazing
• Surface Treatments:Debarring, painting and galvanizing
• Others: Inspection, testing, material handling and packaging
Measurement,Inspection and Testing
• Measurement:Process of assigning a number to an attribute or phenomenonaccording to a
rule or set of rules. Can also be used to refer to the result obtained
• Inspection: Whether the desired objectivesstated by the designer in the specifications have
• Testing: Evaluates product quality or performance.Try to ensure there are no defects to
impair performance,(destructive tests, non-destructive tests, road tests and overload tests).
• Part Dimensions(Part size and shape; size, form, orientation and location of part features)
• Precision:Quality of being sharply or clearly defined; how closelythe indicated value matches • Precision:Quality of being sharply or clearly defined; how closelythe indicated value matches
the true value.
• Resolution:Smallest graduation of the instrument.
• Accuracy: the degree to which an indicated value confirms to an acceptable standard value
• Repeatability:Degree of consistency achieved with a measurementwhen using to measure
the same dimension several times.
• Reproducibility: degree of consistency achieved when used by different people to measure the
same dimension several times.
Three Principles of Measurement
• First Principle: When measuring the dimensions, one must know its temperature
• Second Principle: Avoid the application of force. Non-contactmethods of measurementare
preferred to contact methods.
• Third Principle: The expected precision of the measuring instrument must be 5 to 10 times
higher than the expected precision of the measured object.
• Temperatureaffects the length of all objects and materials
• The coefficient of linear