Protecting Your Ship From Galvanic Corrosion: Drydocking NJ
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- Опубликовано: 9 сен 2024
- In this episode of our drydock series, we're talking about the anodes that are used to protect the ship from galvanic corrosion.
For the playlist of other videos in this series:
• Drydocking New Jersey
To support the battleship's efforts to drydock, go to:
63691.blackbau...
For the most recent updates to the project, go to:
www.battleship...
1,204*23 lbs is 27,692 lbs! That is nearly 14 tons, just in anodes.
Excellent update. It's amazing to see the scale of the protection systems. FYI, it not 'more pure' 'less pure' metals that governs which metal gets consumed, the property is called 'metal reactivity' - the more reactive metal of the pair, gets consumed.
Yes, every time he said "pure" I thought a better term would be "noble" i.e. less prone to corrosion.
Noble is the proper term indeed, as per the periodic table.
@@Ganiscolnoble metals are incredibly non-reactive, hence they are useless in protecting from galvanic corrosion. Google 'metal reactivity' to see a graphic showing the sequence of reactivity - you want to add a more reactive metal so that is consumed, whilst protecting your less reactive metal.
It's amazing how these old ships aren't totally rusted away. Corrosion protection is really an interesting sceince in it's own
The Reactivity Series of Metals….a more reactive metal will sacrifice itself for the less reactive metal. Chemistry is pretty amazing.
Other than confusing reactivity with purity it was a good explanation of corrosion
Lot of Navy ships I worked on had zinc anodes bolted to the bottom of the bilges in the engineering spaces. Most of them were pretty much used up when the ships came in for overhaul. All you'd need is a good flashlight and a large Phillips head screwdriver to loosen the deck plate screws for the hard to see places. 😄
Living in the rust belt with cars, I can relate. Corrosion is the devil.
I was just learning about this in chemistry class, although it was far less interesting when not in the context of a battleship
Where I work someone designed in an aluminum part with stainless screws in it. It's part of a manual valve. Customers were reporting the valve completely failing within 3 months. The aluminum was sacrificing itself in the water that the valve was submerged in
Once worked at a company that made torpedoes. We did test once about corrosion. We observed that you get the most corrosion at the saltwater air interface.
In the 1980s and 1990s, cars were far more beautiful than they are today, and far roomier. However, they had a defect. The gorgeous chrome bumpers were a different metal from the body frames where they mounted. This caused galvanic corrosion. It was rather common to see spotless clean cars with ropes holding on the bumpers because the bumper mounts rusted through, as well as the bolts that held the bumpers on. There were all sorts of aftermarket remedies for the falling bumpers. But, they only delayed the inevitable. My current vehicle has stainless steel bumpers. That was the solution of the manufacturers back then. But the stainless bumpers cost a lot more than the chrome plated bumpers. I bought my current vehicle in 1996. The bumpers are still rock solid.
active cathodic protection is a great thing. helps prevent corrosion, and keeps sea life from growing on the hull. short simple version is anodes along the hull are your positive side, and the screw is the cathode, run thru a shaft grounding assembly (band around the shaft with brushes). just passes a very low current along the hull. much superior to zinc anodes along the hull that need to be replaced periodically, and also cause drag when underway. for a static museum piece, a bolted on anode likely has very little down side.
In the Columbia River freshwater we use magnesium for anodes.
Magnesium has been used for decades in water heaters anode rods. However, if you have well water people have sometimes had to change to Aluminum anodes to remove a rotten egg smell. But that's not a problem here, the two factors here are cost and effeteness, magnesium or aluminum.
@davidmarquardt9034 i replaced my magnesium anode (which was 85% gone) in my HWH with an impressed current system. I am absolutely amazed at how well it works, getting rid of the sulfur smell.
We have a customer who specifies Rolled Alloys brand 310. It has fewer dislocations than the cheaper generic 310 stainless steel. It makes a difference on the stress corrosion cracking
Ryan,. How much are the new aluminum blocks cost? There may be a bunch of us that could maybe help buy the blocks for you. I have seen projects that would allow you to inscribe the block with a name or such. Would be a cool way to help raise some of the funds you need!
This is what I was thinking. Give people a chance to "sponsor" a zinc, including the cost of installation, and in return maybe a certificate could be sent to them, listing the special number of the zinc they sponsored (and its location?) Anyway, an easy fundraiser, like selling bricks to a building.
Brilliant idea.
But make it clear that it will disappear over time 😅
Are Missouri and Iowa in salt water ? They could use those zinc anode to help reduce the cost of their future dry-docking !
Yes they are
It's a dollar per pound dude, worth the cost to go new.
😂😂😂😂😂😂😂😂
Isn’t Wisconsin in salt water as well?
Even though Jersey is in fresher water my guess is those zincs are pretty used up based on their age.
Thanks so much for this seriesRyan. This series has been lifesaving for restoring on my own Iowa-class battleship in my backyard.
My grandfather served on New Jersey during Korea, I would love to get some pieces of her to add to our little "shrine" to my grandfather in addition to his flag and a model of the ship.
You can get pieces of the teak deck in the store!
Thank you..
Ryan, thanks for the videos. Question, do you have a list of "things to do / see" when the ship goes into drydock and they first let you onto the floor of the drydock to see the ship high and dry?
That’s a good question!
for the sake of shipping and making more pieces available for purchase y’all could do what texas is doing to the blisters and break up the sink blocks into engraved 2inch paper weights
just a thought
They could make way more than scrap value that way.
Seems you can replace only half or fewer of the static zinc anodes with a mix of manganese and aluminum and leave the other zincs in place. The zincs are corroding, so they are helping, but the active system is doing most of it anyway. Save money and labor and time and just replace half of the zincs. Use mostly aluminum and a few manganese. That way you are protected on multiple reaction fronts. The static anodes are only a backup to the active system, so they don't need full strength anyway. But they can be there when the power goes out and take over for those short periods. They should last many times longer (as long as the ship?) with the active system doing the majority of the work the majority of the time.
How much does each aluminum anode cost? What about selling them and putting the family name on the anode placed on the ship and maybe a list somewhere of families that contributed? I’d buy one to have my name on the battleship! I will contribute anyway, but I’d love to put my name on a part of the ship as well, even if it is sacrificial.
Wow, I didn't know. The Delaware river was fresh water.
"electricity flows through the water it's going to start to remove molecules from the metals" I think the idea is that depending on the direction of flow of electric current molecules get removed from one piece of metal and deposited on another piece of metal, you just set up the electricity so molecules are not removed from the ship, make the ship the destination for molecules removed from those big chunks of cast iron laying on the bottom
I remember reading a report of an active CP project where they got the voltage polarity the wrong way round.
Ouch. Another case; a welder came out to do some work on a boat and hooked the ground for his arc welder to the pier. As the story was told to me, the boat was leaking within a day. >100A turns out to be able to eat metal rather fast.
So many hobbyists make ROV's, it's surprising the hull doesn't have constant inspection from hobbyists.
HI RYAN GREAT INFO. ALWAYS TO LEARN ABOUT THIS GREAT BATTLE SHIP MAX ,8 AND RON..THANKS,.
You not only need a ton of support, but over 12 tons for all the anodes.
I think either way the anodes you remove get sold off, either for souvenirs or for recycling.
Great video as always!
Ryan, feel kinship with you, also trust physical systems over automated. They work no matter what.
Its not the purity. The more reactive metal corrodes the more electronegative metal. Stainless steel in contact with aluminum will corrode a chunk out of the aluminum because the aluminum is more reactive
Was going to make this point myself, but you beat me to it.
Ensuring that galvanic corrosion protection both passive and active is working and in place should be a high priority. You think $10m is a lot now, wait until you have to replace part of the hull like USS Texas is doing / did if you don't have your galvanic corrosion protection working to protect theship..
I suspect this is lower priority because it actually can be done in the water if you have to. I'd bet it's not designed to be done by divers, but there is no way that someone hasn't figured out how to do it.
That's why you should paint the propellers while in dry dock.
About the condenser. You actually have three metals in play so far as galvanic corrosion goes. There is the zinc anode, the steel in the condenser shell, and the tubes, which are typically some kind of a copper alloy. I think the Navy used to use Monel, but the Marine Propulsion unit in my college Power Plant Design class was 45 years ago, so I don’t remember exactly. I know land side power plants using sea water used Monel.
hi ryan interesting tohear the zinc is bolted on most british canal boats are steel and the zinc ia welded on durimg blacking in dry dock i dont know of the relative merits one of the episodes of cruising the cut covers th subject i look for the link for you
dissimillar metals...our nightmare on my A-7s, hornets, and the others. ))) my sidecar too. miss that thing.
Ifvyoure in a marina on a still night, and there is a poorly maintained boat, you may actually hear a fizz.
If your moored boat is chomping through anodes, your neighbor appreciates the protection😂
Can we get a video on the active cathodic protection system installed on the other Iowas?
my doctor has advised me to keep both eyes in their sockets. is it ok to use one from my collection of glass eyes?. just tell me where to place it
Life expectancy. Reminds me of the story of the B52.
This reminds me of. James Clark Maxwell...
It would be cool if you could wire wheel clean a spot on those zinc chunks, and laser etch or engrave 'Battleship New Jersey' on them. Then, if they wanted to, the customer could polish the rest of it, and put it on their coffee table or desk. Gold or silver plating would look cool.
Ford engineers should have studied the properties of steel a bit more. They may have to recall tens of thousands of vehicles because they used an alloy for valves that fracture if they got too hot during machining. I wonder who came up with that money saving idea.
I once worked at a company that made and sold the anodes. I wonder if any of the anodes are from the company.
I have an unusual question, when the New Jersey goes into drydock, will you be dredging its berthing to keep it out of the mud and to keep the ship level??
Thank you for posting
Why not use multiple types of anodes? Zink, aluminum, and magnesium?
Because the most reactive metal takes it in the shorts. The others are protected not sacrificed.
Immerse metallic magnesium in water (preferably while holding the piece) and see how that works out for you.
Don’t you think the impressed current active protection system might be the main reason the zincs are in such good shape rather than that they are “not working“?
You can think of the active cathodic protection as trying to electroplate the ship (the parts to be protected) but with not quite enough voltage to actually deposit any new metal.
The system you described seemed to use separate anodes (not part of the ship, sitting nearby in the water), but in the comments here others are describing systems where the anodes are part of the ship, either (like the passive anodes) designed to corrode, or (like, say, bronze parts) naturally resistant to corrosion. The former would use shore power when docked, while the latter would use on-ship power while at sea.
Replacing the passive anodes seems like the least time-consuming of your three major drydock tasks and probably requires the least skill, at least until one of those studs shears off. If one anode is done wrong it is no big deal, but if you mess up sealing even one through-hull fitting, you've got a problem!
Why not switch out the zincs with Magnesium anodes which work better in fresh water. I’m just saying it’s very rare for the salt water front to get to Camden.
Is it possible the impressed current system is working as designed to the point it is also protecting the zinc anodes (thus the reason the zinc anodes are not corroding)? Your contractor should be able to clarify this. Hate to see you drop a bunch on money replacing anodes (especially if the current ones are sufficient).
That’s my concern. I am definitely not an expert on cathodic protection, but I have seen bad things happen to underground tanks and pipes when the passive and active system start fighting each other. However, if the zinc isn’t corroding, and the hull isn’t either, it’s probably working correctly.
In an earlier episode, Ryan said they learned that the traditional zinc anodes are not effective in fresh water. This makes sense since the navy was conducting the last dry dock, navy ships spend 99% of their life at sea, and at the time they had no idea that some 10 years later it would become a museum ship. Also it is one of the rare few museum ships moored in fresh water.
✌️
How much monel is used on board?
Hey, about donating... I tried that, but credit card seems to be the only available payment method. Could you perhaps add paypal or something similar, so people outside the US can contribute as well?
What does the new aluminium anode cost each. Could a person buy one with their name stamped into it and it be installed? Boy would I sure have to think about buying one and having my name on it even if it is underwater and unseen. Just a fast thought to generate income to help with all the costs your going to incur.
Will you be selling the zinc anodes?
Meteorologically? That's weather. I think Ryan means Metallurgically. :) He's so knowledgeable we can overlook the occasional boo-boo. :)
We heard about salt water, brackish water and fresh water today. In German, we respectively have Salzwasser, Brackwasser and Süßwasser. The first two are obviously simillar, but is "sweet water" a term used often in english?
No, it’s not lol. However sweet is used when talking about different grades of crude oil depending on the purity 😂
Heard it to describe water fit to drink in the wild
You could avoid the corrosion by making the ship from 310 stainless steel that has been remelted in a vacuum furnace, cold rolled, then soaked in liquid nitrogen to remove as many defects as possible. It would also cost tens or hundreds of billions of dollars
Or use titanium
@@ross82 titanium doesn't weld very good. I reckon its too soft for armor. Aluminum actually has a higher strength for its weight remember aluminut
We’re saving that process for SpaceBattleship New Jersey.
@@chadr2604titanium welds fine
Transparent Aluminum, Ask Scotty the formula.😊
Cool
Sell the new plates going onto the ship and have a donation board outside.
Ryan r the pipes and steam line on the ship drained or r they still holding water?
we still have running water on board, so not all pipes have been drained. they will be before drydocking.
You can recycle all that zinc to make a good amount of money back.
So what did the Royal Navy do about this problem of galvanic corrosion?
Scrapped all our battleships :(
All RN steel hulled vessels have Impressed Current Cathodic Protection systems fitted. I don’t know when they first came into use but I served on Type 42 destroyers that were designed in the late 60’s and in service from 1974 so they’ve been around for a while. In addition zinc anodes were still fitted in areas of dissimilar metals such as hull openings and the shafts; plus moving parts such as the rudders and stabiliser fins.
That’s a lot of zinc!
Everything about this battleship is big.
Sponsor a zinc!!!
In1998 the active galvanic corrosion system on the Missouri malfunctioned and the entire museum staff and 67 visitors were electrocuted. It was the highest death toll ever recorded on a museum ship.
Googled this and nothing came up
Zinc only works in salt water. I thought manganese is what should be used in fresh water.
Pays to watch the entire video
@@ross82 I did. He mentioned using aluminium anodes instead of zinc.
:)
I bet if you turned off your active cathodic protection, you'd have enough electrical juice to rotate a turret...
No
Need a bigger hook up to the electric company
You obviously didn't get the humor...@@tomhenry897
How much money is a block of galvanic blocks
Sounds like you need a diving checklist like active duty ships do…
55th, 27 September 2023
So your telling me I can park my tesla in the river and charge it for free?
Isn't it a conflict of interests to have a company called anode solutions involved with you cathodic protection system? I'm sorry for that joke.. I'll leave now .