390 



SALVAGE TESTS 



Fig. 148. Aquanaut Meeks fires explosive stud into simulated 

 submarine hull near Sealab 



The ten-ton lifting pad (Fig. 146) was successfully attached to a one-thick HY-80 steel 

 curved mock-up of a submarine hull section (Fig. 149). Also, a flat, mild steel patch and gas- 

 ket was bolted to the threaded studs driven into this mock-up with the single-shot tool (Fig. 146). 

 The lifting pad was tested on site by the aquanauts using the 8.6-ton collapsible Sealdbin pontoon. 

 Structural tests of the pad array were later conducted at Long Beach Naval Shipyard following 

 Sealab n. The patch was also tested hydrostatically. 



At the shipyard the padeye device was successfully loaded to 10 tons in all axes without any 

 evidence of studs pulling free. The device was then tested to destruction. The array's plate 

 failed where the padeye swivels. No studs failed. The flat plate patch tested satisfactory to 

 15 psi hydrostatic pressure without stud slippage. 



From a subjective standpoint, all the tools were easily handled and performed to the gen- 

 eral satisfaction of the divers. 



The results of these tests lead to the conclusion that further development and eventual use 

 of these tools by the salvage forces is warranted. This development should include further con- 

 tainment of shock from the single-stud driver and increased penetrating capability for our heavy 

 submarine hulls. The shipyard tests on the padeye indicate need for redesign of the structural 

 part of the device.* 



*The Bureau of Ships, in support of the DSSP program, and with BuWeps concurrence, in sup- 

 port of the DSSP program, has assigned a task to NOL White Oak for the further development 

 of these tools. On-going contracts have been let to MSA by NOL. 



