Due to the wide variety and a large number of objects that can be measured with the micrometer, there is a different classification or type of this versatile instrument. This classification is determined by different aspects or characteristics of the micrometers, which, in turn, are generally determined by the type of measurement to be performed.
Taking into account the different aspects, a micrometer can be classified as indicated below:
According to the technology of the instrument
Mechanical micrometers: the components and operation of this type of micrometer are mechanical. This is the most conventional or common and therefore is used to execute some measurements.
Electronic micrometers: for this type, electronic components are used. Digital technology is also used as a compliment, which results in a completely electronic instrument.
This class of micrometers is also called digital, and they are mainly used to perform measurements in the industrial area or dimensional metrology laboratories. They can cover a measurement range from 25 mm. up to more than one (01) meter, and its standard resolution is 0.01 mm, although resolutions of 0.005 or 0.001 mm can be handled.
According to the standardization of the instrument
Micrometers with standard normalization: in micrometers of this type, the amplitude and the appreciation of the measurements obtained are generally used.
Micrometers with special normalization: the micrometers that have this type of standardization, are used to obtain measurements involved in specific processes such as manufacturing or verifications, so it is necessary to use a measured amplitude and a special appreciation.
According to the unit of measurement of the instrument
Micrometers with the decimal system: the micrometers belonging to this classification, use the metric system, with the millimeter being the unit of measure of length used.
Micrometers with English system: micrometers of this type, use the system of Anglo-Saxon units to make their measurements. In this case, the inch is the unit of measure of length used.
According to the measuring fork of the instrument
Micrometers with a metric fork: micrometers designed to work under the metric system, have screws that measure 25 mm. This allows them to cover lengths of the same range, that is, from 0 to 25 mm., from 50 to 75 mm., etc., reaching and even exceeding one meter in length.
Micrometers with a fork of English system: in this case, the measuring instruments have screws that measure one (01) inch, which allows extreme precision for the operation.
According to the measure to be executed
External micrometer: used to measure the components or external elements of an object or piece.
Indoor micrometer: it is used to take measurements of internal or internal areas of a piece, as well as the diameter of the holes present in it. It has a micrometric head, on which one or more combined axes of extension can be added.
Depth micrometer: it is used to measure the depth of holes, perforations, grooves or grooves present in an object or piece. It has a measuring hood of 25 mm. And has an approximation of 0.001 mm.
According to the shape of the instrument stops
A micrometer with flat parallel stops: these are the most common micrometers and are used to measure flat surfaces.
A micrometer with conical tip stops for threads: these are the micrometers designed to measure between the edges or edges of threaded surfaces.
A micrometer with radial stops: these are the micrometers used to measure the diameter of holes or small perforations present in objects or parts.
A micrometer with gear cymbal stops: these are the micrometers that have cymbals to measure between the teeth of a gear.
There are other types of micrometers, which have a more specific design according to their use.
An external micrometer with three contacts
They are mainly used to measure 3-lip cutting tools, such as strawberries. It has a design in the shape of the letter “V,” and has prismatic angle contact.
Micrometer of the difference of quota
This type of micrometer measures the difference of quota or buckling existing on a surface. To perform this measurement, the instrument has three conical probes which are placed in contact with the surface to be measured, and the central screw of the micrometer determines the buckling difference, taking as reference the points read by the probes.
Micrometer with vernier
This type of micrometer is much more sophisticated, since it allows a much more accurate measurement, by incorporating a vernier (auxiliary Vernier scale) add to its two standard scales.
By incorporating the vernier, the instrument has the additional scale that shows ten marks, numbered 2 in 2, which allows obtaining a level of accuracy of 0.001 mm. or 1 μm (micrometer).
The micrometers and technology
Due to the wide use that is given to this versatile measuring instrument, several online simulators have been designed that can help users understand the operation of different types of micrometers.
There is even an application for mobile devices with the Android operating system, which allows users to make virtual measurements of objects selected by the user, as well as learn to read the measurement thrown by the micrometer.