Metrology Glossary: Geometric Dimensioning and Tolerancing (GD&T)
What Is Geometric Dimensioning and Tolerancing (GD&T)?
Geometric Dimensioning and Tolerancing (GD&T) is a standardized system used in engineering drawings to specify permissible variations in a part’s size, shape, and position. This system ensures that parts are manufactured and assembled accurately, ensuring proper functionality.
- Geometric Dimensioning (GD) outlines the perfect form of a feature, such as flatness or roundness.
- Tolerancing (T) defines the allowable deviation from this perfect form.
What is GD&T Used For?
- Ensuring Interchangeability of Parts: GD&T enables the production of interchangeable parts, allowing components from different manufacturers to be assembled together seamlessly and function correctly. This is essential for the efficiency of assembly lines and maintenance processes.
- Improving Manufacturing Efficiency: By clearly defining tolerances, GD&T helps manufacturers avoid producing parts that fall outside acceptable ranges. This significantly enhances production efficiency by minimizing scrap and downtime.
- Simplifying Communication Between Engineers: GD&T uses a standardized set of symbols to convey design intent, reducing ambiguity and errors in the manufacturing process. This leads to improved quality in the final products.
- Reducing Assembly Time: Parts with precise and well-defined tolerances can be assembled more quickly and easily, reducing production costs and increasing overall throughput.
- Improving Product Quality: GD&T ensures that manufactured parts adhere to required specifications, resulting in higher quality products that perform reliably.
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Further Reading
In this episode, Cross’s Product Specialist, Chris Johnson, explains how to do GD&T tolerancing using the CAD model using two examples, profile of a line and true position.
August 31, 2023
Cross Company is now accredited for the ISO 10360-12 standard, a cutting-edge benchmark for the calibration of portable Coordinate Measuring Machine (CMM) arms and scanners. This allows us to offer unparalleled service, providing a level of certification that goes beyond conventional standards. ISO 10360-12 is a standard to certify the
March 20, 2024
