Introduction to Geometric Dimensioning and Tolerancing
The course is primarily a study of the geometric controls set forth in the ASME standard Y14.5M-1994. The goal is a beginning level ability to interpret a symbolic language used on engineering drawings to communicate geometric information. These symbols limit error for the geometric characteristics of size, form, orientation, and location on selected part features.
In general, the definition of each symbol is reviewed, related tolerance zones are developed and examples of acceptable and rejectable conditions are analyzed. An in-depth investigation of datums is also incorporated. Many of the controls define relationships between part features. These relationships are dimensional in nature and therefore require a specified and repeatable origin of measurement - a datum. Specific topics in this area include: the Datum Reference Frame, simulated datums, datum order of precedence and datum targeting. Additional subjects included are: feature-of-size concepts, effects of MMC, LMC an RFS on tolerance zones, determining "bonus" tolerance, verification techniques using common inspection tools and dial indicators. Students are invited to submit drawings of their own for in-class review and discussion. The use of familiar parts assists greatly in the retention of complex material.
Prerequisites: A solid grounding in blue print reading and basic math skills is a must. Familiarity with basic shop processes, common machine tools and inspection equipment is beneficial but not a necessity.
This course is sponsored by the PA Department of Labor & Industry and organized by the Original Equipment Manufacturers’ . For information on this group call Tammy Marcase at 717-843-3891.