Accession Number:

AD0679179

Title:

HOLLOW BUOYANCY OBJECTS FOR DEEP-SUBMERGENCE APPLICATIONS,

Descriptive Note:

Corporate Author:

NAVY UNDERWATER SOUND LAB NEW LONDON CONN

Personal Author(s):

• Dinsmore,Daniel , Jr

Report Date:

1968-08-13

Pagination or Media Count:

45.0

Abstract:

Small, hollow, polypropylene objects are discussed for use as a low-cost deep-submergence buoyancy material. In the forms of spheres, right hexagonal prisms, and rhombic dodecahedrons, the objects have outside diameters of 4 to 5 inches and wall thicknesses of 0.5 to 1.3 inches. They may be immersed constantly for periods of up to 5 years or more at rated pressures. Objects have been produced for experimental purposes that may be used at ocean depths of over 13,000 feet. Buoy design curves are provided. Buoyancy loss due to initial compression and subsequent plastic creep for ocean depths to 12,600 feet equivalent to a pressure of 5600 psi can be predicted for time periods of up to about 3 years. Mathematical analyses are conducted to determine the stress-strain and plastic creep behavior of hollow, plastic spheres under external pressure. Manufacturing techniques for producing good-quality objects are investigated and the cost per pound of payload buoyancy is estimated for many of the objects. Author

Descriptors:

• *SHELLS(STRUCTURAL FORMS)
• DEEP SUBMERGENCE
• BUOYANCY
• GEOMETRIC FORMS
• PLASTICS
• HYDROSTATIC PRESSURE
• LIFE EXPECTANCY(SERVICE LIFE)
• EXPERIMENTAL DESIGN
• COMPRESSIVE PROPERTIES
• CREEP
• ATTRITION
• PREDICTIONS
• MANUFACTURING
• MATHEMATICAL ANALYSIS
• OCEANOGRAPHY

Subject Categories:

• Marine Engineering
• Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE