Why Don't Metal Ships Rust?
Vložit
- čas přidán 4. 07. 2024
- In this video we ask why metal ships don't appear to rust. We explain a little about the process of rust removal, and show how cathodic protection can be used to help prevent corrosion.
✩SUPPORTED BY PLUS MEMBERS✩
/ casualnavigation
Thank You to all Plus members on Patreon. Your support helps keep these videos freely accessible to everyone across social media.
✩WITH THANKS✩
➼ Images used under license from shutterstock.com
Paint Roller - Kobee / Shutterstock.com
Old Warship - IfH / Shutterstock.com
Pipes - KASIMOV YURII / Shutterstock.com
Postbox - WawroDesign / Shutterstock.com
Radio - AlexBurr777 / Shutterstock.com
Town Scene - VVadyab Pico / Shutterstock.com
Rust Texture - artisttop / Shutterstock.com
Sailor Painting Photo - Ievgenii Bakhvalov / Shutterstock.com
➼ Audio used under license from Epidemic Sound
Edgar Hopp / A Million Upheavals / www.epidemicsound.com
Candelion / Cotton and Strangers / www.epidemicsound.com
Caro Luna / Va a Amanecer / www.epidemicsound.com
Dragon Tamer / Valley of Drakes / www.epidemicsound.com
Kikoru / Land of Freedom / www.epidemicsound.com
✩DISCLAIMER✩
All content on this channel is provided for entertainment purposes only. Although every effort has been made to ensure the content is accurate and up to date, it remains the responsibility of the viewer to determine its accuracy and validity. The content should never be used to substitute professional advice or education. - Zábava
Two essential rules for all new sailors: If it moves, salute it. If it doesn't move, paint it.
salute the props, got it 🫡🫡🫡
Now, what happens when we apply that rule in 20 foot seas where no women are to be found?
i will take this as gospel
What if I just skip the first part?
@@alexn5743 then I guess you're not a sailor so you need to be painted
I spent hundreds of hours at sea on tankers busting rust and painting. On roughly 600 foot vessels it's a never ending battle waged by the unlicensed deck crew. You end the day looking like you just did a shift in a coal mine most days.
The life of a merchant seaman, and the bane of 2nd mates trying to day sleep...
Navy grey paint, applied by her crew
Whose officers thought had too little to do.
Navy grey paint: layer upon layer. The ship has gone down,
Her crew’s on the ground, But the paint is still there.
@@stephenbritton9297 indeed
@@stephenbritton9297haha so true, cutting the jet washer hose line while the geezer gets a cup of tea
Is this stated in your employment contract? Are you getting paid for this? Then you chose it yourself.
It's always blown my mind that sealed sections of hull become completely devoid of oxygen because the steel has absorbed it all to become iron oxide. once there's no more air, the steel can't rust unless more oxygen is introduced. This also means you need to be real careful because people die going into those spaces every year
I recall this being one of the earliest videos this channel has posted in its early days.
I see you're also aware of chain lockers
This same effect can also be used in food storage. Lots of things will spoil when exposed to oxygen, so tossing a packet of iron shavings into the container before sealing it will take all the oxygen out of the container and keep it fresher longer
All you gotta do is say "that's a confined space and I'm not going in there".
Yeah, this channel did a video on that and as a non-sailor, 🤯
For anyone who hasn't seen it, look into Laser rust removal videos. It's a spiritual experience. They use infrared lasers, and iron reflects infrared while rust absorbs it - so the rust vaporizes with zero damage to the healthy metal. Absolutely magical.
Drachinifel took a laser rust remover to USS New Jersy and de-rusted an Orliken AA gun.
czcams.com/video/6C8EgP7g-88/video.html
When i was working on ships the deck crew never stopped needle gunning and painting. Every day was a constant battle against rust. I was a cook and did my best to make sure those guys were taken care of.
The answer is: they do. A LOT. In places you wouldn't expect rust to be a possibility.
If left abandoned.
Theres a old 1930s paddle steamer that over the course of about a decade has rusted quite badly to the point of unsafe, luckily the museum it's at was the shipyard that built her and has the old drydock.
I think this video is lousy if there's no mention of SACRIFICIAL ANODES. Because that's what ACTUALLY keeps the newer ships from rusting. My apprenticeship, if it wasn't cut short was going to involve these.
@@OffGridInvestor They don't keep the ship from rusting, they just slow it down. They do a pretty good job, though. Incidentally, that's also why they invented lead-based paint.
@@OffGridInvestorit's a 5min video. At least focus long enough to watch it and see if it's mentioned before commenting to try and show us how smart you think you are. 🙄
The tupperware!?
The look and feel of metal with at least a dozen somewhat uneven layers of paint reminds me of the sea as much as the smell of the sea does.
USS New Jersey's channel has just gone through their dry docking. It's interesting everything they've had to do to keep it un-rusted for the next 30 years. And all the steps they can skip because it's not expected to move, or be in salt water.
I’m fascinated with this kinda stuff and I respect anyone that doesn’t but I was born and bred in a shipbuilding town and it’s been around me since I was able to understand English. Best wishes 🤝☘️🙏
And they replaced their zinc anodes with aluminum ones while in drydock since they sit in fresh water. I don't understand the chemistry that makes aluminum better than zinc in fresh water. My basic understanding is that the electrolyte doesn't matter just the reduction potential between the anode and cathode.
@@major__kong It's cheaper, but while it has less of a potential difference it's still good enough to protect the ship. Zinc apparently doesn't work quite as well in fresh water too.
Also remember, that they have an "active" cathodic protection system, where they charge the hull of the ship, with a relatively low voltage, of proper polarity, to counter the corrosion electrical potential. Basically "zero out" the voltage.
Plus, the old, removed zinc anodes, are being sold, and are still in pretty good shape. The new aluminum anodes, while also a little cheaper, are less reactive, which is fine for a ship in fresh water. Zinc, in the modern economy is still an inexpensive metal. So much so, that many cast items are made of it. Such as padlock bodies, and pulleys. Lots of cast items, at Home Depot, are made of zinc.
This is only partly true: The other Iowa-class battleships have an impressed-current system - a form of active cathodic protection - installed on board to supplement their metallic passive cathodic protection (e.g. zincs). New Jersey was measured for this system but never had it installed before her last service period, and she was retired and decommissioned before it was installed. Even though she has the fittings for such a system, it isn't physically on the ship as it is with the other Iowas.
This impressed-current system was meant to be used by the battleships in service using powerplant electricity while berthed and while cruising as a means to reduce the maintenance demand of replacing passive protection systems and further supplementing the efficacy of those systems to reduce overall maintenance effort since many areas were found to have suffered from corrosion.
New Jersey is simply special in relation to her sister ships since she doesn't have this impressed-current system on board (even though she could), so the museum as a maintenance-saving effort installed a static impressed-current system on her riverbed berth. It has very little to do with the fact that her water is fresh/brackish as opposed to oceanic salinity or that she wasn't expected to move.
Does it need to be painted?
Yes.
That’s why active ships don’t rust - their crews are constantly working on maintaining them. Cathodic protection also helps, but really, it’s down to good old hard work and care.
Gizza job, I can paint and I need a job?
Not just paint, but "coatings"
Not all vessels at sea are work ships. This applies to the luxury and relaxing vessels as well. Years ago I was surprised when I was on a cruise ship and saw them painting the ship while we were docked. Then I recalled from my geology class how paint is a protective barrier, not just a pretty facade.
A LOT is prevented by sacrificial anodes. They're big. I almost ended up installing them as part of my apprenticeship. I was in protective coatings, all industrial stuff, a lot of oil rig stuff.
I was an industrial painter. Painted a lot of marine vessels, yes they rust. Zinc bars bolted and grounded to the hull helps.
YES. Sacrificial anodes. This SHOULD HAVE been mentioned. I had a similar apprenticeship but part of it was going to involve them.
So does red lead primer
The titanic is not simply rusting away, it is being broken down by bacteria in the water that is attacking the iron that form those rusticles. Without those bacteria the ship would last several hundred more years, and would still be more or less intact (minus the damage from when it hit the bottom of course).
Bacteria...you got me thinking about us, the 80% water beings. There's iron in our blood...and oxygen...and water... 😬
@@user-yp2sc1cy1n I don't see you living at the bottom of the Atlantic anytime soon, don't worry.
@@user-yp2sc1cy1n are ya gonna live at the bottom of the Atlantic for any particular reason? If not, then don't worry 😊
I mean, Titanic is still going to last for several hundred more years.
Amen.❤.
For anyone that’s interested in this topic battleship New Jersey just came out of dry dock and they have several videos talking about there anodes and new paint work. That’s pretty much the main reason they went into dry dock to replace all that. They have an awesome channel, worth checking out!
And they've also covered my favorite, BB-35 the battleship _Texas_ who suffered horribly as well. IIRC, the group restoring the _Texas_ asked the _New Jersey_ group for advice and lessons.
I live nearby and have been visiting it for years, was so excited to see it go by
My initial reaction to the title is "Oh no, they do. That's what the crew is for!" lol
ngl the rust chipping is really satisfying
Chipping is.... Needle-gunning is not!
@@Chris-hx3om Maybe that's why we just kept adding new layers, and never stripped any off. We did strip the wax off the deck every time. I would know--I'm the guy they always put on those two jobs, waxing and painting, but only because I always did an outstanding job of it.
You showed it but I didn't notice it said. And it bears saying :
- Rust is bigger than iron. So when a tiny bit of iron at the bottom of the smallest ding in the paint rusts it swells. And pushes at the paint. And makes the crack bigger. And exposes more iron. Also, this increase in size causes the flaking. Which exposes more iron.
Yes, it was said... 1:30
I enter massive oil storage tanks. The old onss are rhe most dangerous because the rust has used up a lot of the oxygen in the air.
Lack of oxygen and H2S being present means full SCBA when working
I see way too many CZcams videos of people going into old steel enclosed structures. I always worry about someone dying while doing this sort of exploration.
... and all the permits and spotters and .....
@@Chris-hx3om ... prior and ongoing ventilation...
H2S is no joke and it forms from all kinds if things that people don't suspect. Good way to die fast
Another approach is to make the ship out of something that won't corrode because the oxide forms a fully protective layer on it (for instance, titanium) or doesn't oxidize at all at normal temperatures (for instance, fiberglass or carbon-fiber). This is expensive (titanium is a real pain to work with), but at some point the expense in materials may be less than the expense in paying for continuous maintenance.
There is a good reason the modern (somewhat tounge in cheek) version of the classic HOLD FAST knuckle tattoo of deckhands seen sometimes on Bosun’s mates is BUST RUST written across the knuckles.
When I was a kid, one of the coolest things was the navy’s motor torpedo boats. And they were selling a few old ones…and I was excited. Then my father told me the original hull thickness and the current thickness, which was much thicker. I was too young to really understand rust, but he made sure I understood these hulls would require a lot of work to fix.
And then there's the Black Sea, which is anoxic, so metals at the bottom have lasted centuries without corroding.
Very nice episode. Topic which was confusing me for a while is clearly explained. Thanks.
So, are you going to add an another video about why the HMS Warrior is still in existence?
She was left out to rot for almost a century!! The first fully iron warship....
Actually one of the best channels on CZcams.
3:57 galvanized nails? how about galvanized square steel? 😂Intresting video good job.👍
little johny
@@giganticyeti368 eco friendly wood venners.
I am a big fan of this channel. Keep up the good work! Change nothing!
I was just watching a video from a lobster fisherman where he explained why they were putting zinc sacrificial pieces to the hull of their lobster boat
A similar trick was used on all wooden ships, there pole worms were the risk and to keep the worms out of the brunt of the wooden hull soft wood was put on that was also sacrificial material.
Very well explained
There are also electrical based systems. Battle Ship New Jersey has done a few videos about protection systems. They recently dry docked and used aluminum, I believe, because they have an active system installed underneath the ship.
I was very interested to hear mention of applying tannic acid to deal with rust. We boil iron/steel small game/beaver traps in wood chips and leaves to blacken them and assist in rust protection.. very cool to suddenly understand that this technique/chemical process (tannic acid) is way more widespread than I thought.
Nice explanation, thanks ⛵
literally saw this at work while waiting in line to tour a US Navy ship some minor repairs and repainting done to a cruise ship docked behind it, with the navy ship rusting away in multiple spots where paint wore down as it wasn’t due for a repaint for a couple of months when the ship moved homeports
thats actually nuts, idk how i never new this before.
Check out Rust Base coating. It’s the best corrosion protection paint for metal ships. Made in USA.
Annodes are still used in modern ships inside of ballast water tanks
Read The Last Grain Race by Eric Newby. He was a seaman on a steel sailing ship that went from Britain to Australia and back to get Australian wheat. When there was no other work and the weather was fairly mild, he and other lower-ranked seamen had to chip away excess rust and paint over the exposed steel.
Another great video.
Interesting subject. Thank you. 👍
take a shot every time this guy says "anyway"
I bet somewhere there is a bosun trying to figure out how to get a work gang down to the TITANIC to start busting that rust and get paint on it! :)
I am now thinking about the tens of thousands of barrels of toxic liquids that have been dumped into oceans and seas during the past couple of hundred years or so.
Just uploaded.. happy days 👍👍
Great video. :)
This was very interesting
BOIS WAKE UP CASNAV POSTED!!🚢🛳⛵️
I both love and hate fiberglass. It doesn't rust but it's really not fun to repair.
Any examples of ships in drydock where we can see an anode? I have never seen one, but I'm not entirely sure if it should be as visible as the illustration shows.
Let’s all give a thumbs up if we think this video deserves more views!
somehow forgotten that todays ships are build with marine-steel, stainless steel 316L. Which is an alloy of iron, nickel, chromium and molybdenum. This alloy is specifically developed to withstand salty water.
U have NO IDEA
@@barryuppman9212 u had a chance to clarify
Fascinating
My god, 'the Titanic is corroding away at such a rate that it will be gone one day'. That sentence was so useful that you may see the point of it one day.
and how often is a tanker drydocked for fixing rust and paint? every month? year?
The ss great Britain is pretty much solid rust. Go and have a look.
Keep in mind, in salt water iron rust faster
do u think u can do a video similar to the Andrea Doria video of yours. but with the SS Principessa Jolanda 1907. the ship that sank at launch fully furnished
Next videos in this series: "Why Isn't The Sky Blue", "Why Are Politicians Never Corrupt", "Why Do Wooden Houses Never Burn Down"
You missed impressed current cathodic protection which all ships have. A power supply is used to create the potentials and the anodes are made of something like titanium which is extremely corrosion resistant. The protection is given without the sacrificial anodes corroding. And sacrificial anodes are still fitted should there be a loss of power as a backup.
I was really hoping this would be covered. I knew about anodes but the newer systems still seem like black magic to me. I would really like to know more about these modern systems.
@@ddegn they aren't really that new. The ship I was on in the Navy was designed in the 60's had an impressed current system. I use this kind of system on the hot water heater in my home. It's about the same equipment as used for electroplating but with lower voltages and currents as you're not trying to plate the surfaces. Just prevent them from corrading.
@@ddegn The REAL black magic with corrosion systems is the way their effectiveness is measured, silver-silver chloride cells. I studied it for over a year (and became a 'subsea inspection engineer'), and I still struggle to understand exactly how it works. 🤪
The titanium is typically plated in platinum. When I saw platinum at the top of the electro potential chart, I was waiting for this to pop up!
@@carmenrepucci today mixed metal oxides such as IrO2/Ta2O5 are used in place of platinum.
So why would you put an anode on a fiberglass or wooden hull if there's no metal to rust? Does it protect the hull in some way, or is it only to protect the metal components in the ship and if that's the case then could you attach the anode directly to the engine instead of the hull for instance?
My marine diesel engine is rawwater meaning saltwater cooled and has three zincs inside the cooling passages. All metal under water inside or outside of ship need to be protected due to stray currents easily penetrating even fiberglass hulls. Radiant
There are two important factors how quickly ferrous metals on seagoing vessels rust: Salinity and temperature.
The higher the salinity and the higher the temperature the faster the decay.
The Titanic e.g. is in an evironment with relatively high salinity but low temperature (usually about 4°C).
The worst situation are tropical oceans with high salinity and warm water.
Since you talked about the Titanic, i think you should have also mentioned that corrosion does not occur (or works very very slowly) at extreme depths because of the lack of free oxygen radicals (?) in the water at depth.
I find it funny that "rust" is just "iron oxide". Yet it is the only oxide we gave a special name.
Probably because we, as humans, have encountered iron oxide since we first started smelting iron. Just like how certain elements like iron, copper, silver, and gold all have weird letters on the Periodic Table.
Meanwhile water
"Patina" is the word used for copper oxides, to describe the greenish tinge that copper gets as it oxidizes.
@@ImieNazwiskoOK Water is the most useful monoxide we know.
Alumina is aluminium oxide
That is so clever
2 seconds in the video : I work as a welder on a shipyard. they rust. they absolutely do. make no mistake on that. repairing an old frigate right now. rust everywhere.
…and at around 3 minutes he explains that in his usual clear manner.👍
You should try watching more than 2 seconds, see if there's more information
@@DaveSCameronpretty sure it's a stab at the click bait title 🤡
@@robmckennie4203you should stop defending click bait
Thanks
Another word for rust is iron oxide.
There are many metal oxides and what they all have in common is that they have "adopted" oxygen atoms to bond with, which of course breaks down the crystalline metal structure they once had.
Aluminium oxide, Zinc oxide, Carbon Monoxide/Dioxide, Hydrogen peroxide... They are all elements that have bonded with oxygen, and they all have different effects when they come into contact with other elements or molecules or heat etc.
Also, oxygen is formed by Greek/latin words. Oxy standing for "birth" and Gen standing for "giver/producer" and if one wants to have a meaning that we can understand in English, oxygen is an acid. It is THE acid really. Most other acids (aside from fluoride) are made of oxygen and hydrogen compounds. With some form of accelerator like sulfur in sulfuric acid or, H2SO4, meaning it has 2 hydrogen bonds, one sulfur and four oxygen bonds. That's right, sulfuric acid is more than 50% oxygen that is ready to let go of the bonds it has with sulfur and attack most other compounds.
The least acidic form of oxygen is when it's simply bonded with hydrogen... H2O or quite simply... water.
But, if you add even the tiniest amount of salt (natrium) into the mix you now have a quite potent oxidizing agent, also known as salt water.
The "Rust Belt" has it's name for a reason... Every vehicle and most other things exposed (like steel bridges) are rusting away at a rapid pace.
Why? Because snow/rain in winter is mixed in with road salt, which forms said corrosive agent known as salt water.
The reason ships don't rust is because they are painted in quite THICK and resistive layers of paint. They even used to be quite toxic and some still are when they need EXTRA protection.
And they are regularly maintained and painted, all in an effort to keep metals away from salt water.
There's another good reason stuff in the desert really only rusts lightly... There's 1, not much moisture in the air, 2 the baking sun evaporates any moisture.
Oxygen simply doesn't have a co-reagent to work with in the desert most of the time.
Still, the heat from the baking sun WILL accelerate any rusting when it occurs in the desert. Which is why you usually find abandoned vehicles where anywhere water can pool, still is rusted clean through while the rest of the vehicle looks almost pristine.
In short, you don't want water to sit in direct contact with any metal for very long and ESPECIALLY not if temperatures are high. Look at your typical exhaust headers/system for evidence of what heat does to metal when water is mixed in. Rust galore! Or should i say oxidation hell?
I didn't expect this video to be this interesting. Could also be the weed.
can I apply this concept to my car?
Can I do this to my car?
Yes, and you absolutely should fix any visible rust.
Constant maintenance and painting. The main reason is sacrificial anodes. Like in your hot water heater tank. They go on the hull of the ship and the stuff that would eat the metal of the ship goes after them instead. And when they're eroded away enough they are replaced.
so can I use cathodic protection on my car to prevent rust? would it work?
They also periodically replace large sections of hull that are corroding dangerously close to failure.
I’ve owned a few steel boats. Got rid of them because I couldn’t keep up with the interior rust hidden in inaccessible places.
Rust is my favorite color.
Wonders of Molybdenum. Added to steel to make A4 stainless steel. I think they're starting to use it in fuel cells too as catalysts.
Rust mentioned let's go
So can I bolt a brick of zinc to my GM shit box to make it last longer?
Because for obvious reasons they're very well painted, even to marine specifications 😮
1:50 To any mechanics or engineers out there, I've always wondered: when you remove rust, you're just chipping away the metal structure, right? It saves the rest of it from the rust, but there's also less metal on the structure, thus making it weaker, right? So my question is: after a certain point of rust removal, when/how do you determine you need to just remove that whole segment of the structure and replace it? Or do you not, and just call the entire thing a loss after a certain point?
left unchecked...applies to everything nowadays
I always felt sorry for it being called "sacrificial anodes" 😂😂😂😂
What can be done for automobiles?
Question: at 2:30, as the wind is blowing from aft, pushing the ship forward, how come the flags are blowing towards the stern? 🤔
Maybe on a tack, you can definitely go faster than just the windspeed.
Cause it’s painted. Saved you the entire video
I wonder if I can use this on a car?
The hms titanic is runsting. however at as much reduced rate due to the low oxygen content of sea water af those depths. the main reason is is losing its structural integrity is due to iron bacteria which literally eats away at the iron (reacting it with oxygen) for nourishment. this is why pain is still needed on modern ships.
Take a look at the BCF fleet.
I've heard ship welders saying that they are practically doing nothing but trying to weld rust together.
In Neal Stephenson's Baroque Cycle, some slaves of one of the Barbary states trick their masters, take over, and steal the silver and gold off a Spanish treasure ship. They manage to get to southeast Asia with it, and build a new ship...and put the gold on the hull, to hide it, and to protect the ship from ship worms & barnacles. Kinda expensive, but seems like it'd work. In the story, it works out perfectly--their enemies board the ship, looking for the gold, but can't find it.
check out the videos on the battleship new jersey channel. they just spent 2 months in drydock and removing rust and repainting the hull and replacing anodes was the #1 thing they did.
Almost as amazing as preventing rust is getting paint to be the same colour
3:10 woah woah woah there. CAThodes are PAWSitive, and anodes are negative.
More cringe than bubsy 3D.
On a diode (in open position) the cathode is negative, on a battery (while discharging) it is positive. It's about the direction of current flow, not the polarity of the circuit. If you use technical (conventional) current (+ flows to -) then the current leaves the cathode and enters the anode. If you need a cringy verse: the CAT left, ANY minute it could come back. 😝
"Why don't..."
"They do."(slap)
I've just finished work experience on a 61 year old ship (God I love Poland) and 75% of our time was spent scraping rust. 😭
Road sign posts never seem to rust?
They usually aren't made of iron.
Then what?
In Europe, they're usually galvanized steel. Maybe that they're aluminum in the US.
Aluminum here in Canada.
Anodenized alluminum.
Why is SS Great Britain shown as a paddle wheeler? SS Great Britain is a screw ship, Great western was a wooden hulled paddle steamer...
Something something galvanized square steel, something something bolts bottled from my aunt, i knew someone is going to make a joke about this
They do!
Rust never sleeps
Slight problem, the Great Britain was a propeller ship and not a paddle steamer.
Yeah more like a lack of research on his end.
The clip would be accurate if it was the Great Western.
for me as a "old cars guy" this looks like a horror short film😮