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I am looking for any studies or maps detailing the average salinity and temperature for areas of the Earth's oceans. As an extra if anyone has data or maps on areas with large amounts of in-trained silts or aggressive sea life (muscles/barnacles) that would be a huge help.

Purpose: I would like to write a paper for Navy engineers on specific world areas of concern for equipment operation utilizing seawater cooling systems. That way we can gear our preventive maintenance to account for these problems.

Fred
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Christopher Wojtan
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    I once got an excellent answer by a Navy engineer in Engineering SE.I've posted a link to this in their chat room just in case. – uhoh Feb 13 '20 at 13:13
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    this question should have been split into two or more questions,one for the corrosive water and one or two for the aggresive life in the water,one is blocking cooling water for the engines the other type eat wood and many types grow on the hull with its own set of problems. – trond hansen Feb 13 '20 at 21:46
  • Sea water is all very corrosive. Using it for cooling removes two variables ; temperature and velocity. The third variable is marine life ( causes "under deposit" attack and oxygen differentials ). -Polluted areas may be more corrosive, depending on pollutants. But generally the specific composition of the sea water is inconsequential to the variation of corrosion potential. – blacksmith37 Feb 14 '20 at 15:32

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Sea water is all very corrosive; the precise composition is not significant. Steel structures are cathodically protected with impressed current and/or sacrificial anodes, usually aluminum. For equipment to be cooled with seawater there are a few choices ;However, for the Navy where reliability is more important than the cost , titanium would be the material of choice ( Type 2 , but types 1 and 3 or the Pt alloy - forgot the number- are also good).The variables for sea water corrosion are : temperature, velocity, sediment, and marine growth, not composition. Inco/Huntington probably evaluated every possibility for sea water corrosion at the La Que labs in Wrightsville Beach NC. Work done before Harvard MBAs' in management eliminated "research" from "research and development". Papers will be published under "Seahorse Institute" and NACE ( National Association of Corrosion Engineers). NACE will have various current publications available for sea water corrosion ( located in Houston TX). Most of this R & D was done before the internet so it won't be available on-line.

blacksmith37
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  • Thank you. Your right we do use Titanium coolers but only for select equipment because our pipes are either stainless or are 90/10 NiCu. That requires us to use isolators in order to prevent the bolts from disintegrating. Most of our coolers are steel shell and tube types. Some areas of the world have sea conditions that just chew through pipe like no bodies business. Thats why I really wanted the data to narrow down the areas that will cause the worst problems for ships so we can create a maintenance advisory for ships operating for prolonged times in those areas. – Christopher Wojtan Feb 14 '20 at 18:56
  • You probably also have some Monel ( invented by Inco), and nickel aluminum bronze, also CA 6NM propellers. Deposits are a potential problem even with the higher alloy stainless tubes; One remedy is to run a brush through the tubes , on line at some time interval. . I expect there are NACE publications that will be useful . I remember there is also a NACE committee for corrosion of military equipment. – blacksmith37 Feb 14 '20 at 20:00