Figure 1 1 . Vented glass pipe specimen assembly attached to head of 

 18-inch pressure vessel (left). 



In order to standardize the test procedure and to eliminate as many 

 variables as possible, all tests in this phase were conducted with 4-inch-ID x 

 6-inch-long Pyrex pipe with flanged ends. The glassware was procured 

 through normal commercial glassware supply channels and was used in the 

 "as received" condition. 



Five specimens each of the following simple glass pipe-to-end closure 

 plate combinations were tested to determine critical pressure using the same 

 procedures as described under the Phase I tests. 



Aluminum 6061-T6 



Stainless steel type 316 



Brass (naval) 



Titanium (Ti-6AI-4V) 



Phenolic resin— glass fiber laminate 



3.63 inches thick 

 2.58 inches thick 

 2.58 inches thick 

 1.82 inches thick 

 4.40 inches thick 



Figure 16 shows typical samples of the end closures used. 



The variation in end-closure plate thickness from material to material 

 is a result of the relative strengths of the materials and the calculated thick- 

 ness required to resist failure at an operating pressure of 20,000 psi. 



Table 3 shows the results from short-term critical pressure tests with 

 the various end-closure materials. 



12 



