Geometric Dimensioning and Tolerancing (GD&T): BS 8888 and ISO
This course provides an essential understanding of the symbolic language of GD&T within the context of the latest BS 8888 and ISO GPS standards. Delegates will learn how GD&T is used to convey design intent, guarantee both function and assembly, and, maximise tolerances.
Description
After the course you will be able to:
• Have an essential understanding of all the symbology used in BS 8888 and ISO GD&T and, how it is used to meet design intent and remove ambiguity
• Understand how the geometrical characteristics of features determine their functionality
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• Understand how datums and theoretically exact dimensions work, what they are for and how to select them
• Understand the 14 types geometric tolerances, how they are related and what each one will control
• Dimension and tolerance a feature to guarantee it will assemble with a mating part and provide additional tolerance in the process
• Calculate tolerance zone boundaries
• Understand how each and every one of an array of tolerance zone modifiers may be used to increase or refine tolerance whilst ensuring the features meet their functional requirements
• Understand how to dimension and tolerance patterns of features
• Read and apply GD&T correctly
• Appreciate how geometric tolerances may be inspected
• Work in compliance with BS 8888:2020 and ISO standards
Topics covered:
• Introduction to GD&T, BS 8888 and ISO GPS, and, design intent
• Principles of GD&T
• Size and non-size dimension features, the envelope requirement and independency
• Datums, datum features and datum feature simulators. How to select datums and the effect of datum precedence.
• The 14 types of geometric tolerance
• How to use the MMC modifier to guarantee the assembly of features; boundary calculations.
• Other tolerance zone modifiers and datum modifiers. Giving extra tolerance whilst guaranteeing functionality
• Tolerancing of patterns
• How to apply GD&T
• Specifications of edge conditions and surface finish