Reinhart 



prolonged periods of time could result in destruction of the links 

 due to the internal stresses created by the formation of corrosion 

 products. 



Wire Rope 



A number of metallic wire ropes were exposed at various 

 depths and for different periods of time. These were plow steel, 

 galvanized steel, aluminized steel, stainless steel and 90 copper- 

 10 nickel clad stainless steel ropes and cables of different types of 

 construction. 



The zinc on the 0.125 inch diameter, 7 x 19 construction, 

 lubricated galvanized aircraft cable was completely covered with 

 red rust after 403 days of exposure at a depth of 6,780 feet. In 

 addition, the breaking strength had decreased by 50 percent. 



The amount of zinc remaining on the other galvanized ropes 

 varied from none in the case of the 0.094 inch diameter, 7x7 cable 

 which was 100 percent rusted on the outer surfaces to considerable 

 remaining on the 0.25 inch diameter, 7 x 19 construction cable which 

 was dark gray. There was no loss in the breaking strength of any of 

 these five cables. 



After 403 days of exposure at a depth of 6,780 feet the 

 smaller diameter (0.094, 0.125 and 0.187 inch diameter) stainless 

 steel cables lost considerable strength, 90, 86, and 96 percent 

 respectively. These decreases were all attributed to crevice cor- 

 rosion of the internal wires. Many pits were also found on the 

 individual wires away from the breaks and some broken ends were pro- 

 truding from the cables prior to testing. 



There was no loss in breaking strength of the three larger 

 diameter stainless steel cables, the inside strands were chiefly 

 metallic color with only a few localized rust spots. 



Two types 304 stainless steel cables clad with a 90 percent 

 copper-10 nickel alloy were exposed for 402 days at a depth of 2,370 

 feet. One cable, 1x37x7 construction with a 0.3 mil thick clad 

 layer was covered with rust on the outside but the inside wires were 

 uncorroded. The other cable, 7x7 construction with a clad layer 

 0.7 mil thick was covered with green corrosion products on the out- 

 side, uncorroded on the inside strands and had lost no strength. 



Three aluminized steel cables (7x7, 1 x 19, and 1 x 19 

 construction) with 0.6, 0.6 and 0.7 mil thick coatings lost no 

 strength during the 402 day exposure at a depth of 2,370 feet. The 

 7x7, 0.187 inch diameter cable was covered with white corrosion 

 products and a few light rust stains but the inside strands were 

 dull gray in color. The outside surfaces of the 1 x 19 construction 

 wires (0.250 and 0.313 inch diameter) were gray in color with scat- 

 tered white corrosion products covering about 50 percent, of the 

 surfaces. The inside strands were a dull gray color. 



Eight wire ropes were stressed in tension equivalent to 

 approximately 20 percent of their respective original breaking 

 strengths. There were no stress corrosion failures after either 751 

 or 1,064 days of exposure. However, the breaking strength of the 



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