Ford_某汽车GDT形位公差培训材料_全集.pptx

GDT for Body;Course content课程内容;Introduction介绍;What is GDT什么是GDT;What is GDT什么是GDT;Authorisation批准;Application;Application;More information;How GDT Relates to Ford;The 5 Step Process;5 Step Process;Step 1;Utilise new design concept;Master Control Plan;Master Control Plan;Step 2;Establish Datum Reference Frame;Datum Reference Frame (Reference Pocket Guide, Page 8);Datum Features;Primary Datum Plane;Primary Datum Plane;Primary Datum Plane;;Datum Target Areas;Datum Target Areas;Secondary Datum Feature;Secondary Datum Feature;Secondary Datum Feature;Supporting a panel on the designated Datum Target Areas, and using the four way locator removes another 2 Linear degrees of freedom, resulting in all 3 Linear, and 2 Rotational degrees of freedom constrained.;Tertiary Datum Feature;Tertiary Datum Feature;Tertiary Datum Feature;Supporting a panel on the designated Datum Target Areas, using the four way, and two way locators removes all six degrees of freedom.;Step 3;Common Terms and Definitions;Material Conditions;Maximum Material Condition;Least Material Condition;Regardless of Feature Size;Virtual Condition ;;;Geometric Controls;Feature Control Frame (Reference Pocket Guide, page 3);Geometric Characteristic Symbol;Geometric Controls;PERPENDICULARITY;PERPENDICULARITY;;POSITION;POSITION;The term to describe the perfect (theoretical exact) location of individual features in relationship with a datum reference or other feature(s). In general the POSITION control is used to locate uniform features of size, e.g. holes, shafts, slots etc. ;Verification;Position Tolerance Zones;Positional Tolerance Zone 1(Cylindrical);;BOUNDARY;BOUNDARY;As no Diameter symbol precedes the positional tolerance, a non cylindrical zone is inferred.;BOUNDARY;;;;BOUNDARY ;Zero at MMC concept;Zero at MMC concept;;Example of current specification;;Example of current specification;Zero at MMC concept;;;;Composite Positional Tolerances;;Composite Positional Tolerances;Composite Positional Toleranc