Accession Number : AD0710350

Title :   STRUCTURAL DESIGN OF CONICAL ACRYLIC VIEWPORTS.

Descriptive Note : Final rept. Apr 67-Apr 69,

Corporate Author : NAVAL CIVIL ENGINEERING LAB PORT HUENEME CALIF

Personal Author(s) : Snoey,M. R. ; Katona,M. G.

Report Date : JUN 1970

Pagination or Media Count : 67

Abstract : A time-dependent, yield-failure criterion was developed and utilized in the analysis of a variety of viewport configurations. A RANGE OF THICKNESS/MINOR DIAMETER RATIOS FROM 50.25 TO 1.75 AND INCLUDED ANGLES FROM 60 DEGREE TO 120 DEGREE WERE ANALYZED BY THE FINITE ELEMENT TECHNIQUE. Using the viewport structural analysis in conjunction with the yield-failure criterion for acrylic, time- dependent operating depths were determined as a function of viewport configuration. An experimental investigation was performed to validate the analytical results. Six full- scale viewports were tested for a year under simulated operational conditions that included simultaneous cycling of pressure and temperature, 0 to 4,000 psi and 70 to 35 F, respectively. Comparison of analytical and experimental results indicated excellent agreement for the physical location of viewport failure at specified loading histories. Design recommendations are presented in the form of design curves which enable the design of a conical acrylic viewport for a specified operating pressure and duration under load. Design information is given also on sealing with a conventional 0-ring, as well as guidelines for elevating a viewport in its flange. (Author-PL)

Descriptors :   (*UNDERWATER VEHICLES, VISIBILITY), (*STRUCTURAL MEMBERS, DESIGN), ACRYLIC RESINS, OPERATION, CONICAL BODIES, FAILURE(MECHANICS), SEALS, STRUCTURAL PROPERTIES, THICKNESS, EXPOSURE(PHYSIOLOGY), VISCOELASTICITY, PRESSURE, LOADS(FORCES), HYDROSTATIC PRESSURE, O RINGS, SHEAR STRESSES

Subject Categories : Marine Engineering
      Structural Engineering and Building Technology

Distribution Statement : APPROVED FOR PUBLIC RELEASE