A gauge serves as a reference standard for predetermined dimensions and shapes. The teaching embodies the physical measure or the form ( measuring standard ). Gauges are used in metrology, production and assembly.
A teaching is used to test and not measure . Because with a gauge, no numerical value can be determined, but only the target condition (gauge) can be compared with the actual condition of the test object. Tolerances can either be found in the applicable standards or are determined according to design aspects.
Gauges are used to check standard dimensions. Their application usually contains fewer sources of error than a measurement and provides a clear statement (good or reject). A multi-level statement (two tenths exceeded, three tenths not yet reached) is also possible.
Adjustable gauges can be used to remove and transfer default dimensions. The default dimension can be taken from a sample or a 1: 1 representation, taken over by a measuring device or set directly. Lockable calipers and compasses , for example, are suitable as adjustable gauges .
Gauges in measurement technology as well as in mechanical and plant engineering usually consist of hardened tool steel , while the measuring surfaces are made of hard metal and are usually finely ground or lapped .
Combinations of teachings with measurement tools are often used as teaching called. For example, when a molded part adapted to the test item is provided with several dial indicators. In the automotive industry, for example, crankshafts, valve covers or bumpers are often measured at several points at the same time, and in some cases also aligned directly. The entire test or measuring device specially manufactured for a single part can then be referred to as a gauge.
The vernier caliper , often referred to as "vernier calipers" (southern German) or "sliding calipers" (Austrian), is usually used for measuring, but can often also be used as a gauge. Because if it has a locking screw or clamp, any number of identical parts can be checked for a preset dimension.
- Measure gauges belong to a set of gauges in which the measure increases from teaching to teaching. See gauge blocks and feeler gauges
- Form gauges enable radii, angles, tapers, threads, etc. to be checked.
- Limit gauges embody the maximum and minimum permissible dimensions of bores, shafts and threads
Teaching in practice
- Drilling jigs define the geometric position of the hole on a workpiece
- Plaster gauges are wooden or metal strips that, when attached to the wall, enable flat, horizontal or vertical plastering surfaces
- Falsework places the geometric shape of a structure z. B. Bridge or arch fixed
- Bullet hole testers are used in shooting sports