Nominal size

In manufacturing, a nominal size or trade size is a size "in name only" used for identification.^[1] The nominal size may not match any dimension of the product, but within the domain of that product the nominal size may correspond to a large number of highly standardized dimensions and tolerances.

For example, dimensional lumber sizes such as "2 by 4" refers to a board whose finished dimensions are closer to 1 1/2 inches by 3 1/2 inches. A "3 1/2 inch" floppy disk standard dimension is 90 mm, or 3.54 inches, and is advertised to hold "1.44 megabytes" although its capacity is 1,474,560 bytes. A "3/4 inch pipe" in the Nominal Pipe Size system has no dimensions that are exactly 0.75 inches. A screw thread has a number of dimensions required to assure proper function but is referred to by a nominal size and a thread design family, for example "1/4 inch, 20 threads per inch, Unified National Coarse".

A nominal size may not even carry any unit of measure, for example 120 film is a film format made by different manufacturers, interchangeable in cameras but with no particular correlation to "120" in either inch or millimetre units. American wire gauge is a series of sizes for copper wire, with an arbitrary but well-standardized relationship between the size number and the dimensions of the finished wire.

Nominal sizes may be well-standardized across an industry, or may be proprietary to one manufacturer.

Applying the nominal size across domains requires understanding of the size systems in both areas; for example, someone wishing to select a drill bit to clear a "1/4 inch screw" may consult tables to show the proper drill bit size. Someone wishing to calculate the load capacity of a steel beam would have to consult tables to translate the nominal size of the beam into usable dimensions.

See also

• Paper size
• Trade gallon
• US standard clothing size
• Caliber
• Preferred number
• Battery nomenclature

References

1. ^ R. K. Rajputpage A textbook of manufacturing technology: (manufacturing processes),Firewall Media, 2008 ISBN 8131802442 page 705

This industry-related article is a stub. You can help Wikipedia by expanding it.v · Categories: Measurement Industry stubs Wikimedia Foundation. 2010. Игры ⚽ Нужна курсовая? Nominal sentence Nominal techniques Look at other dictionaries: nominal size designation — vardinių matmenų žymuo statusas T sritis Standartizacija ir metrologija apibrėžtis Sutartinis raidinis skaitmeninis žymuo, susijęs su matuoklio matmenimis. atitikmenys: angl. nominal size designation …   Penkiakalbis aiškinamasis metrologijos terminų žodynas nominal size — specified size, stated size …   English contemporary dictionary nominal size tubing — Tubing measurement which has an inside diameter the same as iron pipe of the same stated size …   Dictionary of automotive terms nominal — I. adjective Etymology: Middle English nominalle, from Medieval Latin nominalis, from Latin, of a name, from nomin , nomen name more at name Date: 15th century 1. of, relating to, or being a noun or a word or expression taking a noun construction …   New Collegiate Dictionary nominal —    Used to describe standard sizes for pipe from 1/8 inch to 12 inches (3.2 mm to 304 mm.) The nominal size is specified on the basis of the inside diameter. Depending on the wall thickness, the inside diameter may be less than or greater than… …   Lexicon of Cave and Karst Terminology nominal diameter — A characteristic value used for pipeline systems to identify parts which belong together such as pipes, pipe joints, fittings, etc.; a nominal size for the inside diameter …   Dictionary of automotive terms Nominal Pipe Size — (NPS) is a North American set of standard sizes for pipes used for high or low pressures and temperatures.[1] Pipe size is specified with two non dimensional numbers: a nominal pipe size (NPS) for diameter based on inches, and a schedule (Sched.… …   Wikipedia Nominal impedance — in electrical engineering and audio engineering refers to the approximate designed impedance of an electrical circuit or device. The term is applied in a number of different fields, most often being encountered in respect of: The nominal value of …   Wikipedia nominal filter — A filter capable of cutting off a nominated minimum percentage by weight of solid particles greater than a stated micron size …   Military dictionary nominal scale — the weakest qualitative, not quantitative or ordered, classification of the samples into separate categories so that each possible result belongs to only one category, with the categories not able to be ordered relative to each other, e.g., one… …   Medical dictionary 18+ © Academic, 2000-2024 Contact us: Technical Support, Advertising Dictionaries export, created on PHP, Joomla, Drupal, WordPress, MODx. Mark and share Search through all dictionaries Translate… Search Internet Share the article and excerpts Direct link … Do a right-click on the link above and select “Copy Link”