Seawater resistivity

In soil, anodes are connected by cables to the object to be protected. The cable must be low resistance in order not to reduce the current delivery. Therefore with long lines, the cable cross-section must be proportionately large. A cable with NYM sheathing with 2.5 mm Cu is mostly sufficient. Occasionally stronger cables and special insulation are required, e.g., NYY 4 mm Cu. Power supply cable buried in soil should have a noticeably light color. For use in seawater, occasionally temperature, oil and seawater-resistant cable is demanded, e.g., HOVRN. ... 

Various concentrations and purities of aqueous ammonia are on the market. The typical concentration is 25% to 30% ammonia and the iron content is less than 10 ppm. If the ammonia content is above 25%, it must be shipped in pressure vessels because of its elevated vapor pressure. For more stringent purity requirements for aqueous ammonia, the containers should be made of seawater-resistant aluminum (magnesium alloyed) or austenitic steels74. 

Gunmetal CuSnlOZn2 to Seawater-resistant, hard alloy with very good... 

Alloy with high strength and elongation, good castability and seawater resistance. 

Rotes p = Seawater resistivity (flm) L = length of anode (m) r = anode radius (m) S = arithmetic mean of anode length A = exposed anode surface area (m9-... 

In practice, galvanized parts of locks were free of rust after 11 years in brackish water. Galvanized pilings in seawater resisted rusting for 4-8 years. 

The rotary valves are two-position stainless-steel valves (Valeo Instruments, Inc.) with four to ten ports. The first two valves, 1 and 2 in Fig. 23-1, which are exposed to seawater, are made of Hastelloy C-22, a seawater resistant nickei-chromium-molybdenum alloy. The three valves in the heated zone (3, 4 and 5), if installed inside the GC oven, are equipped with high-temperature rotors, specified by the manufacturer (Valeo) to operate at temperatures up to 340 °C. AU valves can be actuated electrically for various degrees of automation. 

B. Wallen. 1981. Seawater resistance of a high molybdenum stainless steel, in Proceedings of the Second BSE-NACE Corrosion Conference, Bahrain, 140-151. 

Fig. 1 plots resistance factors for the three Berea core sections as a function of xanthan solution throughput (for 0.1% X US K K36 xanthan in seawater). Resistance factor is defined as brine mobility divided by polymer solution mobility. Assuming that the permeability of the core is fixed, resistance factor is the effective viscosity of the polymer solution in porous media relative to brine. Fig. 1 demonstrates that the resistance factors in the second (middle, longest) and third (last) core section were quite stable during the course of X US K K36 xanthan injection. Resistance factor averaged 3.8 in the second core section and 3.1 in the third core section. Thus, no in-depth plugging was noted within the core. 

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