I. INTRODUCTION 



This report presents the results of the experimental stress 

 analysis of the Hull No. 2 of the Aivin series. All attachments 

 to the submarine hull were installed prior to conducting the 

 test. 



II. INSTRUMENTATION 



A total of 74 locations were strain gaged, 38 inside and 

 36 outside with two gage 90 rosettes. The strain gages were 

 located as shown in Figure 1. 



The gages were micro-measurement EA- 06- 12STA- 120 

 and were bonded on by Eastman 910 cement. A 48-channel 

 Gilmore strain recorder was used to record the strains. The 

 Alvin was first cycled to 500 psi four times to stabilize the 

 gages. 



III. DESCRIPTION OF THE PRESSURIZATION TESTS 



The hull of the Alvin was tested in the 90" inside diameter 

 test tank at Southwest Research Institute. 



The hull was seated on a steel ring frame and held in place 

 by 2, 650 lbs. of weight placed inside the hull on a temporary 



