boom in a vertical attitude during sweeping to minimize loss of oil 

 under the boom. A secondary objective is to provide a single point for 

 towing during field use. The two towing assembly candidates considered 

 are shown in Figure 2. The advantages and disadvantages are presented 

 in Table 2. 



Bulkhead Attachment 



Bulkhead attachment assemblies are needed to provide a leak-tight 

 seal with a dock or other vertical surface during tidal variations. The 

 assemblies may also be used to provide a load-carrying seal between a 

 skimmer craft and the connecting boom. The two candidates for this 

 component are shown in Figures 3 and 4. Table 3 presents the advantages 

 and disadvantages of the two designs. 



DESCRIPTIONS OF SELECTED DESIGNS 



All of the design candidates were determined to be structurally 

 sound for the anticipated design loads. Therefore, the final selections 

 of the recommended design from among the candidates was based upon the 

 fulfillment of the design requirements for the boom hardware. 



After review of the design candidates, the tubular assembly of the 

 boom connector shown in Figure lA was selected as the basic unit for the 

 assemblies, primarily because of its advantage over the other candidates 

 in its insensitivity to decoupling and its rotational flexibility. Fig- 

 ure 5 is a dimensional sketch of the recommended design. 



Several items are of interest in the final design of the boom 

 connector hardware. 



Aluminum alloy 6061-T6 was selected for all assemblies because of 

 its high strength and good extrusion properties. The 5000 series of 

 aluminum alloys has a higher marine-corrosion resistance but are much 

 lower in yield strength than the 6000 series. With the 6061-T6 alloy 

 the connector is strong enough to withstand forces which would be 

 placed on the connector during operation, yet it is light and requires 

 no buoyancy tanks. The extrusions are cut to fit the overall height of 

 each type of boom size, and all corners in contact with the boom end 

 are rounded to minimize abrasion (see Figure 5) . 



The female connector tapers outward and upward to a wider 

 diameter at the top to allow insertion of the male connector without 

 the disadvantage of aligning the two connectors in a vertical or near- 

 vertical position. This makes it relatively easy to connect the sections 

 in an open- sea situation. 



If the female and male connectors are pulled apart , sufficient 

 elasticity remains in the jaws of the female connector to permit reuse 

 of the connector though subsequent failure would occur at lower tensile 

 loads. 



