These Metals Destroy Themselves to Prevent Rust

An overview of cathodic protection, which includes a rust prevention gunfight in my garage.
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Making a structure last as long as feasible before it needs to be replaced is not just good stewardship of assets. It is a way to keep the public safe and prohibit environmental failures too. Corrosion is one of the #1 ways that infrastructure deteriorates over time, so cathodic protection systems are a necessary contraption for keeping the created ecosystem safe and sound.

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This is not engineering advice. Everything here is for informational and entertainment purposes only. Contact an engineer licensed to practice in your area if you need professional advice or services. All non-licensed clips used for fair use commentary, criticism, and educational purposes.

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  1. Practical Engineering

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    • @C2K all the way through the video I was thinking he’s about to mention boats.

    • What about CORTEN steel test?

    • @Green Steve IKR!

    • You forgot to mention water heaters

    • 7:52 Can you do another experiment like this, but this time, use ALL 3 anodes on the same metal plate, like a tower & see what happens.
      I guess the magnesium is dissolving first to protect the other 2 nodes, then the aluminum & lastly the zinc one.
      Most interesting question about this, can multiple metals (or an alloy of all 3 metals combined) work better & longer than any one of them individually?
      One way I think this could fail to work (at least as an annoy) is if the magnesium dissolves first & create like a “metal foam” that has worse contact with the iron.

  2. The diagram at 3:26 shows the removed material (rust) moving through the base metal. This is incorrect. The lost metal moves through the water electrolyte.

  3. Can’t paint rebar? Hmm. Has anyone tried? Can’t see why you can’t use prepainted rebar.

  4. to show how dramatic the rust pockets were, you could have put a ruller on edge across the sample with a light behind it. the light would showcase how big the gaps are. id assume the gaps would be much smaller on the last sample

  5. @9:44 American car manufacturers experimented with that. They introduced a small electric charge to the body which in theory staved off the corrosion process.

  6. Your water heater has a cathode that should be periodically checked and replaced but no one does.😂

  7. Just saying, showing that people can open any kind of control panels for pipelines might be be a little risky.

  8. My family had my grandfather galvanized so he wouldn’t rust . . . 🤔

  9. Anode protection has been around for decades, Boats & ships use them & hot water tanks have them, also the passing of a charge has been used for a time now, so why all of a sudden for your video topic? Running out of interesting topics maybe?

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