WINDOWS FOR EXTERNAL OR INTERNAL HYDROSTATIC PRESSURE VESSELS. PART IV. CONICAL ACRYLIC WINDOWS UNDER LONG-TERM PRESSURE APPLICATION AT 20,000 PSI.

Conical acrylic windows of 30-, 60-, 90-, 120-, and 150-degree included angles have been subjected in their mounting flanges to 20,000 psi of hydrostatic pressure for up to 1,000 hours in the 32F-to-75F temperature range. The displacements of the windows through the flange mounting have been recorded and are graphically presented as a function of time, temperature, conical angle, and thickness-to-diameter ratio for the ready reference of the designer. A detailed study has also been made of the types of failure and of the dimensional and structural parameters that must be considered in the design of safe, operationally acceptable windows for long-term service under hydrostatic pressure of 20,000 psi. The test results indicate that a minimum thickness to minor diameter ratio of 2 and an included conical angle of 90 degrees or larger is required to provide safe and optically acceptable windows for long-term sustained pressure loadings of 20,000 psi. Author