surface of 



glass lapped 



to remove 



irregularities 



flange section 

 of 4-inch-ID X 

 6-inch-long 

 Pyrex glass 

 pipe 



1/8-inch soft copper 

 / (solder, used to join 

 /ashers) 



Figure 22. Experimental sealing and 

 bearing system utilizing a 

 composite copper— steel 

 washer between the glass 

 pipe end flange and the 

 metal end-closure plate. 



permit the washer to slide on the end 

 closure as the diameters changed with 

 pressure. If this system performed as 

 hoped, it would not only reduce the 

 stress concentrations in the glass— seal 

 bearing area but would also largely 

 eliminate tension cracking of the glass 

 pipe end flanges caused by the glass 

 "dragging" on the end closure as it 

 attempted to change diameter in 

 response to changing external pres- 

 sure. Neither this system nor the 

 similarly designed lead bearing washer 

 system described below performed 

 satisfactorily at 3,000 psi. Examina- 

 tion of the failed specimens showed 

 many small cracks which originated 

 in the glass— metal bearing area and 



Figure 23. Aluminum, composite copper— steel, and composite lead— steel 

 washers showing the relative depth of indentation resulting 

 from pressurization of experimental sealing and bearing system 

 assemblies to one cycle at 3,000 psi external hydrostatic pressure. 



24 



