Metrology Meaning |What is Metrology?
It is the scientific study of measurement. Metrology is the branch of science dedicated to measurement
Metrology Definition:-
It is defined as the science of measurementprimarily concerned with the establishment, reproduction, conservation & transfer of units of measurement & their standards.
Basics Of Metrology Audio Tutorial:-
Importance of Metrology:-
- To achieve standardization.
- Used for minimizing the cost of the inspection.
Types of Metrology:-
- Legal/Scientific metrology.
- Deterministic/Industrial metrology.
Classification of Metrological Instruments:-
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Terms Which Relates with Metrology
Inspection:-
Checking of quality characteristics of a given job.
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Need for inspection:-
- To develop a reputation for the company.
Meanwhile, Interchangeability can refer to Interchangeable parts, the ability to select components for assembly at random, and fit them together within proper tolerances.
Example:-
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Accuracy & Precision:-
Accuracy:-
The ability to do something in an exact manner. It is nothing but a degree of correctness.
Precision:-
Precision refers to the closeness of two or more measurements to each other.
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All of the above figures show exactly what is accuracy and what is precision.
Sensitivity:-
Firstly sensitivity is the ability to receive sensations.
Moreover, Sensitivity is the ability to measuring instruments to detect small variations in a quantity being measured.
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Calibration:-
- Validation of specific techniques and measurements of equipment.
- Comparison of measurements with a known standard or other devices.
- Scientifically assessing a system’s response to known controlled signal inputs.
Define Calibration:-
Firstly calibration is defined as a set of operations that establish, under specified conditions, the relationship between values indicated by a measuring instrumentand the corresponding standard.
OR
In addition, The Calibration process is a comparison of one instrument’s response with that of a reference instrument of known response and accuracy.
Repeatability:-
It is the ability of the measuring instrument to give the same value every time, the measurement of a given quantity is repeated under the same conditions.
Traceability:-
It is related to taking reference to a national or international standard.
Reproducibility:-
It is the quantitative measure of the closeness of the agreement, between the results of measurement of the same measured. Carried out by changing the method of measurementobserver, measuring instrumentlocation, condition of use, time, etc.
Different Types Gauges In Metrology:-
1.Radius Gauge:-
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2.Screw pitch gauge:-
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BUY Screw Pitch Gauge On Amazon
3.Filler Gauge
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Errors In Metrology Instruments
The difference between the true value of the size is measured and the value found by measurement is called Error.
Types of error in measuring instruments:-
- Systematic error/controllable error
Concept of least count of measuring instruments:-
Least Count/Resolution:-
The smallest dimension that can be read on an instrument is called as least count of that instrument.
For example, in below mention photographs of the scale, visually we can conclude that there are 5 lines between 0 and 1, which means 1 line indicates 2mm means 0.2cm.
Therefore the minimum reading that can be measured on this instrument (scale) is 0.2cm.
Hence we conclude that this scale has the least count of 0.2cm.
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Metrology Instruments
Vernier Calipers:-
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Two Scales on vernier caliper one is the main scale and another is vernier scale
Therefore, as a result
The formula for Least Count & Total Reading (TR) On Vernier:-
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Micrometer
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Therefore, as a result
The formula for Least Count & Total Reading (TR) On Micrometer:-
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Make sure you also check our amazing article on Quality.
Similarly, you should download our amazing android application regarding Metrology & Quality Control
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