assembly at the bottom to hold the anode. The steel pipe was hinged at 

 the top to permit easy inspection of the anodes. The anodes were placed 

 about 2.5 feet from the side of the piles and about 6 feet below low 

 water. 



Direct current ripples , resulting from difficulty in producing 

 constant voltage direct current from rectified alternating current 

 electricity, are reported to be detrimental to the life of platinized 

 titanium anodes (Lowe, I966). However, the report states that on smaller 

 systems it is usually more economical to use lower current densities and 

 thicker platinum films instead of the expensive three-phase installations 

 or voltage smoothing systems. 



f. Anode Installation . Manufacturers produce a variety of sizes 

 and shapes of galvanic anodes. Some are equipped with special facilities 

 for mounting. 



One of the primary design problems in cathodic protection systems 

 is the provision of an arrangement of anodes which will adequately and 

 efficiently protect the structure concerned and yet withstand destructive 

 forces from wave action, ice, boats and floating debris. Cathodic systems 

 designed to protect structures such as sheet pile bulkheads may be de- 

 signed with anodes resting on the bottom. However, the useful life of 

 anodes resting on the bottom may be reduced due to pitting caused by non- 

 uniform environment. Also, unstable bottom conditions may cause excessive 

 coverage of the anodes by sediments and reduce their effectiveness. These 

 factors should be investigated if this type of installation is being 

 considered. Systems designed to protect numerous vertical members, such 

 as piling supporting a pier, may use anodes suspended between piling at 

 a depth sufficient to lessen the possibility of damage by floating objects. 

 Some of the more recent installations have anodes supported on pipes which 

 are hinged at the top or mounted on cables that can be wound up on winches. 

 These methods provide for easy removal of anodes for inspection and aid 

 in prevention of storm damage. 



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