Measurements are one of crucial parts of not only mechanical engineering but all types of engineering fields. Every branch of engineering involves two processes: design, and operations and maintenance. The design may be machine design, building design, circuit design, transportation design, automobile design etc. The operations part involves operation of the machines, automobiles, various plants, circuits etc.
Both, the design, and operations and maintenance involve measurements. For instance while designing automobile we have to consider dimensions of various parts of the automobiles, the loads they can pick up etc. Similarly during the operations of the plant, say like industrial refrigeration plant, we have to measure parameters like pressure, temperature, etc. In the power plant we have to measure various quantities of the coal, the quantity of water in the boiler, the amount of steam produced along with its flow rate, temperature and pressure, the amount of power produced, the outlet temperature of the steam from condenser etc. In the large chemical plants large number of such parameters have to be measured.
In the field of civil engineering, measurements play dominant role. Right from the initial process of designing and drawing, laying the lines, raising the foundation to the construction of walls, designing of structures, centering, and all the finishing works, large number of measurements are involved. There is hardly any stage in building construction, where we don’t need measurements.
Once Lord Kelvin said, “I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it, but when you cannot express it in numbers, your knowledge is of meager and unsatisfactory kind: it may be the beginning of knowledge, but you have scarcely in your thoughts, advanced to the stage of science, whatever the matter may be.”