Photoelastic models were used to indicate stress patterns in various geometrically designed shapes. Each model represented a two-dimensional cross-section of the interior portion of an axially symmetrical porcelain electrical insulator. Five different loading pins were combined with three loading heads to produce eleven models. The maximum stress in each model was determined using a photoelastic method of stress analysis. An attempt was made to select the best structural design to be used in an electrical insulator. The test results indicate that the most desirable stress distribution is obtained using a single step loading pin and that the loading head angle and loading pin angle should be approximately equal to twenty-five degrees measured from the vertical plane --Abstract, page ii
