introduction to mechanical measurements and metrology

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Introduction to mechanical measurements and metrology

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  • Metrology: The fabric of science and technology

  • What is metrology?The science of measurement;Metrology includes all theoretical and practical aspects of measurement. The word comes from Greek (metron), "measure"+ "" (logos), amongst others meaning "speech, oration, discourse, quote, study, calculation, reason". Examples: distance, time, mass, temperature, voltage, values of physical and chemical constants

    Metrology bY IGS

  • Why is metrology important and interesting?Standard units and values of constants needed for all science. Technological standards make all technology work better. Measurement of constants can give fundamental insights into the universe.

    Metrology bY IGS

  • Engineering metrology is the science of measurements of lengths and angles and such other quantities in precision measurement which can be expressed in linear or angular units. Metrology deals with the standards for basic units like length, mass & time and also for derived units velocity, acceleration, force, pressure etc. Metrology is concerned with the establishment, reproduction, conservation and transfer of units of measurements and their standards. It is not restricted only to standards of length and mass but other parameters in sectors of social concern, such as health, safety and environment protection also.

  • Measurement is a complex of operations carried out by means of measuring instruments to determine the numerical value of the size, which describes the object of measurement. It is an inevitable process in our day-to-day life and for any measurement process standards are necessary. The basic objective of a measurement is to provide the required accuracy at minimum cost. Measurements have definite role in achieving product quality, leading to industrial competitiveness, consumer protection and related benefits.

  • Basic function of all branches of engineering is design: design of manufactured goods, design of machinery to perform the manufacturing operations, design of power sources, design of electrical and electronic apparatus, design of roads and waterways and another function is to provide proper operation and maintenance of such equipment which require measurement without which function could not be properly performed. Metrology deals with measuring instruments for measuring dimensions which is the vital role in all manufacturing industries. Relevance of the Course

  • Mechanical measurements involve the measurement of force, torque, pressure, temperature, strain etc which plays very important role in controlling the variables like pressure, torque etc in processing industries, automotive components design etc. Metrology and measurements is useful for post graduate streams of mechanical sciences and forms the basic entity for research work. This subject knowledge is required for the complete life cycle of the product from design to manufacturing to inspection.Relevance of the Course

  • The knowledge of metrology and its practical applications is of vital importance in the modern competitive industrial environment. The most important factor in achieving quality and reliability in service of any product is its dimensional control. Knowledge of this subject is required for processing industries (Ex: Chemical industries), manufacturing industries (Ex: automotive industries), meteorology (weather monitoring), and in general in every aspect of life this subject finds its application. Application areas

  • DefinitionsThe science of measurement is called "Metrology", or, sometimes, "Measurement Science. It deals with the calibration of measuring devices and the statistical methods used in determining the bias, precision and uncertainty of measurements under defined conditions, such as in a laboratory environment. It also encompasses the use of measuring devices under less than ideal conditions,such as found in a factory or outdoors environment, or the "real world".

  • Why Measurement?To have a better understanding and knowledge about the systems and processesAccording to Lord Kelvin, the 19th century British scientist who invented Absolute Zero (among other things) to prove their point: when you can measure what you are speaking about and express it in numbers you know something about itTo control the variables better

  • Why Measurement (cont)Measurements and measurement devices are important to more than just scientists and engineers. They impact everyone's life; Some examples:the bills for items that are metered? Such as: Electrical power, water, natural gas or oil, and the time you spend, literally, on the telephone are charged according to some measuring device. the weigh scales in stores?

  • Why Measurement(cont.)In manufacturing: the temperature of a process; the flow rate of fuel; the speed of a production conveyor. Others:temperature of a sick person; weight of a space vehicle.

  • Measurement DevicesMeasurement devices are an absolutely critical link in getting quantitative knowledge. So, too, are the ways in which one uses them.

  • CalibrationA measurement device must have a trusted calibration and work with a known measuring error under the conditions prevailing when the measurement is made.

    Calibration is related to the science behind a given measurement device and is often supported by a traceable chain to more accurate measurement devices, sometimes called standards.

  • UnitsNumbers and attributes are, however, by themselves not enough. Measurement results are always expressed in terms of units or the ratio of properties or attributes having the same units.

    There is a big difference between a journey of 2 meters and 2 kilometers. A journey of 2 (unspecified) is meaningless without knowing what the 2 means!

  • SI: The International System of Units

  • Temperature: Kelvin, Celsius, and Fahrenheit

  • Some human-referenced units of measurement To concludeevolution of measurements