Metrology is the science of measurement, and the determination of different physical quantities such as force, temperature, and dimensions. Metrology is derived from the Greek word for measure, and it is commonly understood that anything can be measured and can be expressed with numbers. Metrology uses different units for measurements; all units however use numerical processes to describe the object in question. This may seem quite complex, but it is quite simple; as long as you remember that universal standards need to be used for measurement.
When talking about metrology in the engineering field, length can be denoted as being the most important parameter; other parameters that are not of such importance in the field of engineering are mass, force, and time. Metrology can therefore be said to be the language of science, using units of measurement to produce forms of equal standards and uniformity; visit http://www.cam-machine.com to find out more.
To ensure that parts are correctly manufactured in engineering, the most up to date techniques for instruments and measuring and calibration are used. By use of CNC machining and CAD software, metrology for engineering has become far more simplified, metrology no longer relying on the human eye or having to make allowances for human error. There are many terms used in metrology for engineers, some of the most important being as follows:
Measurement
The determination of an unknown dimension using universal measuring standards; known standards are needed in order to make comparisons.
Basic Dimensions
This refers to the targeted dimension for a part that is to be produced, and it will be associated with the tolerance. The tolerance is the allowable variation that can be allowed in a basic dimension before the part is no longer acceptable. The tolerance of parts in precision engineering is extremely small and ensuring that all parts are engineered to perfect is extremely important.
Dimensional Metrology
Dimension metrology is the use of instruments to determine the form and size of objects. Dimensions of the object must be measured or specified.
Limits
Limits define the dimensional range of the object, accuracy and precision being implied to ensure that the desired results are achieved. The reliability of a CNC machine will alter depending on its accuracy and precision; precision is a higher form or accuracy, and one that is used and required when producing precision parts with CNC machinery.
The accuracy and precision of CNC machines in the modern world has been made capable through the use of CAD software. Whereas in the past a machine worker would have to use the above metrology techniques to draw scale drawings by hand, CAD software that uses vector lines can now produce models that are entirely accurate and free from any human error. A CNC machinist needs to be familiar with not just CAD software for CNC machines, but with all the definitions used in metrology. A CNC machinist is a highly trained professional who through programming of a computer can allow a CNC mill or turner to produce the very highest standard of precision parts.
No comments yet.