Figure 12. Cable silver-soldered to chain link. 



Specialized Zinc Anodes With Steel Cables 



Repairs and Fabrication. The modification of the cathodically 

 protected mooring was accomplished when both it and the unprotected 

 control mooring were scheduled for their periodic removal and rehabilitation 

 ashore. 



The total cost for rehabilitation of the control mooring amounted 

 to $4,617 of which $2,000 was for pickup and installation and $2,617 was 

 for repairs. The unprotected ground ring assembly was loose, and all rivets 

 needed replacing. The pear links were badly pitted, and the thickness was 

 reduced in places to 1-1/2 inches (a loss of 40%), necessitating their replace- 

 ment (Figure 13). The chain thickness for the first five links on all legs had 

 been reduced to about 1-7/8 inches. 



The cathodically protected mooring required no repair work, but 

 the ground tackle was recoated by dipping the sandblasted chain into a tank 

 of cold-applied coal tar coating. Ml L-C-18480A. The anodes on the ground 

 legs had lost very little zinc while providing the current necessary for cathodic 

 protection. Those nearest the ground ring had generally lost slightly more 

 zinc, because higher potentials had been provided in these areas. The two 

 smaller anodes located in the sea chests built into the buoy cone also had 

 lost relatively little zinc. 



22 



