Tolerance coning is the engineering discipline of creating a budget of all tolerances that potentially add/subtract to affect adequacy of a particular parameter. This is particularly critical where stages of design/manufacture precede test/use.
For example, when setting a test limit for a measurement on each manufactured item of some type, to assure that no bad items are shipped, the limit must be tighter than the requirement to allow for the worst case sum of measurement inaccuracies (e.g. equipment,
test fixture
A test fixture is an environment used to consistently test some item, device, or piece of software. Test fixtures can be found when testing electronics, software and physical devices.
Electronics
In testing electronic equipment such as circuit ...
etc.). The design of the item thus has to take into account not only the product requirement but also the test tolerances. The buildup of this budget is tolerance coning.
Electronics engineers intuitively do tolerance coning and tend to formalise it for critical parameters. However it is also relevant to other engineering disciplines.
See also
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Test method
A test method is a method for a test in science or engineering, such as a physical test, chemical test, or statistical test. It is a definitive procedure that produces a test result. In order to ensure accurate and relevant test results, a test ...
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Engineering tolerance
Engineering tolerance is the permissible limit or limits of variation in:
# a physical dimension;
# a measured value or physical property of a material, manufactured object, system, or service;
# other measured values (such as temperature, hu ...
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Tolerance stack
Tolerance analysis is the general term for activities related to the study of accumulated variation in mechanical parts and assemblies. Its methods may be used on other types of systems subject to accumulated variation, such as mechanical and elec ...
Engineering concepts
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