Some additional tidbits of research:
1. When electrically isolated copper sheets are exposed to periodic immersion in seawater, the corrosion rate is ~.07mm/year, or roughly .003 inches per year for the first year. That rate increases with time however.
2. This rate is not realistic for swimming pool situations for several reasons:
a. Velocity:
Many metals are significantly affected by the flow velocity of seawater. For example, in the case of copper, there is a
critical velocity, above which the corrosion becomes excessive.
However, when the velocity of seawater is less or equal to 1 m/s, copper behaves well, without any significant corrosion rate. Seawater velocity can cause corrosion of special forms, such as corrosion-cavitation; a phenomenon resulting from the joint action of corrosion and cavitation
critical velocity, above which the corrosion becomes excessive.
However, when the velocity of seawater is less or equal to 1 m/s, copper behaves well, without any significant corrosion rate. Seawater velocity can cause corrosion of special forms, such as corrosion-cavitation; a phenomenon resulting from the joint action of corrosion and cavitation
b. Temperature: The rate above was for 60 degrees F.
c. The problem that corrosion is not uniform over the whole pipe surface, making it easy to develop pinholes without any significant loss of average thickness.
d. The aerated water in a swimming pool is more corrosive than water with the same chemical content but with less dissolved oxygen.
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