Hydrostatic Release Unit (HRU) | Rigging and Operation
HTML-код
- Опубликовано: 27 сен 2024
- Hydrostatic Release Units (HRUs) allow your liferafts to launch automatically should your vessel sink. They only work if they are fitted correctly.
A correctly fitted hydrostatic release unit (HRU) will also allow you to quickly launch liferafts manually in an emergency using the senhouse slip.
This video will show you the principles of fitting a hydrostatic release units (HRUs) correctly as well as their internal operation. Understanding how hyrdostatic releases work helps you to fit them correctly and, ultimately, to keep yourself safe on the water.
Music from Jukedeck - create your own at jukedeck.com
--------------JOIN OUR COMMUNITY---------------
We have launched a new community of maritime enthusiasts over on Patreon.
★ / casualnavigation
When you join, you will become part of an Exclusive Community, gain Early Access to our RUclips videos*, receive Exclusive Content* and have influence over Community Videos*
*Everyone becomes a part of our community, but additional rewards will depend on the tier you select.
------------------------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.
I have absolutely no interest in boats or sailing whatsoever, but I love your videos. Very insightful, thanks
Thanks Gehteuch. Glad you are finding them interesting.
Be careful you might fall down a rabbit hole and bing watch all of this channel and move on to other Naval channels. Might I recommend Drachinifel. If you want another soft spoken Englishman who talks about Naval stuff. Mostly warships then I can thoroughly recommend.
same here mate
Gehteuch Nixan lmao same
Those are cool devices!
Saved for someday when I own a yacht!
Owning a Yacht or a Jet will Bankrupt you. No, what you have to do is Lease it! That way you temporarily have it to yourself but you don't have to do all the expensive stuff like Maintenance, keeping it seaworthy, cleaning, etc.
@@Macintoshiba steal one
Terrible idea by the way please dont
@@toasterhavingabath6980 I also like taking a bath with my pet toaster
@@toasterhavingabath6980 the owners would probably never notice. I've seen sailboats stay still on drydock for years, same with parked cessnas as well, an airfield near where I lived closed a few years ago, and it was a nightmare trying to figure out who were the owners, how to contact them, and tell them to move the plane with expired licensing, at their expense.
And some of the owners are dead, and it's even harder to find who "inherited" the parking fee, and the moving fee.
Sometimes, if you just don't tell them they won't notice it's missing.
Lots of free boats. Just go to any marinara and ask. X
Could we get a video on how the inflation mechanisms of rafts work?
Inside each white shell there're a couple of compressed CO2 canisters (the exact number changes depending on the size of the raft).
That orange rope you see in the video, tied to the weak link, is attached on the other side to a valve on the CO2 canisters.
When the ship is sinking it pulls the rope down, but the raft pulls up as it would float even deflated. That force open the valve on the canisters, releasing the CO2 and inflating the raft.
Finally, the now inflated raft (with its higher bouyancy) pulls on the rope much harder, breaking the weak link and releasing itself from the sinking ship.
I don't study or even touch water, but the knowledge you're putting out is the reason why old people say wow, youtube and the internet would've made me a millionaire in my day. Thank you for the knowledge dear friend, YOU ARE a master teacher. I have my brother who's 6 with me (I'm 21) and I always make him watch videos like this for a bribe and your channel is easy for him to understand and follow along. Thank you, keep up the outstanding work, and keep on smooth sailing :) a like is headed your way, so is another comment to boost your stats. I'd be an inferior man if I can't help the man who's expanding my knowledge!
Thanks Mr3344555. Glad you are enjoying the content and finding it useful. Your support is appreciated!
Many years ago I took command of a 37m (121ft) motor yacht. All 4 HRUs were incorrectly rigged in different ways. The outgoing captain, who was not around for a handover, was an incompetent fool in dozens of areas.
Thanks, didn't know much bout this, something never on tv docus. Not likely I'll be on the water again but always good to know how stuff works, great ch, very educational.
Excellent explanation as always thank you.
Thanks Alister!
The HRU is critical. I used to work in the commercial fishery and there were many stories of fisherment who cabled or even CHAINED down their raft only for later the raft to go down with the boat. Knowing how to properly set up the hydro is a true lifesaver!
When I was in the Navy, our ship's Safety Equipment Officer was taking me through the workings of a HRU, as I wanted to know how they worked, just in case. But he finished up with, If the HRU fails, it will be the least of your worries. My first thought was of course, the ship is going down. He then looked me dead in the eye and said to me, I would be more worried anything unsecured rocketing to the surface from the downed vessel. He then proceeded to walk away, leaving me to contemplate his statement.
i am a cadet i would like to take the time and thank you for your videos , it's crazy how much knowledge i acquired from you.
keep it up
Why am I watching this ? I'm on leave. This is work.
I have learned a lot of interesting info from your channel on maritime stuff.
These videos are addicting and way better than what a television can deliver or an expensive education.
finally one video which clears all my doubts by explaining it beautifully.. thanks
Do be aware of the water depths your ship/boat is operating in. If the raft's painter length exceeds depth of water, the raft may not inflate after being released by the HRU. You will still need to to manually haul out the remaining painter, finally giving it a sharp tug to cause inflation. Great video, thanks!
Wow! That's some scary stuff. Seems idiot proof but people still mess up securing them properly. You'd think if your life depended on it you would triple check that it was properly done.
I wonder why it’s is not delivered as black box so people can’t plug it upside down.
Complacency is part of the answer.
Idiot proof? That seems idiot proof? You have some genius idiots in your neck of the woods. That device seems WAY easy to install improperly or to overly secure because you don't trust the mechanism. Or for corrosion to damage the auto-detach mechanism. Or for someone rushing to do maintenance to forget to properly secure the painter. Or like any number of easy-to-miss/easy-to-forget checks.
@@x--. that's why you have weekly SOLAS checks and annual surveys....
When you make something idiot proof. The world makes a better idiot.
I watched this video last year and I'm proud it's recommended to me again
I have been on boat a bit and always wounded how release system works. Thanks.
How simple yet ingenious mecanism. Keep up the good work.
Thanks Milan. It is a great little bit of kit. Simple and efficient.
@@CasualNavigation I do dislike the "weaklink" part, but I guess, if it's done correctly it should work all the time.
I love your video so easly to be understood
Such a simple and effective design, superb engineering
Good and simple explanation! 👏
Thanks mzee
This gives me some Payday 2 vibes. During the yacht stealth mission, sometimes me (we) had to search those capsules. At first I didn’t really knew their purpose until I found this video, so thank you.
I am so impressed with your animations! Excellent work!
Feb 5th, 2021, 285000 Subscribers. I just discovered this channel and I tell you, if this guy will keep making videos this channel will habe a few mil. subscribers in the next years. Awesome content. Very interessting.
i've seen HRU installations where the rigging loop was upside down - low friction point shackled down, HRU cutting in between the painter attachment and the deck shackle. Those installations, won't open the raft, right?
Terrifying. This seems like something that crew could easily overlook and complacent masters would never check. The sort of thing that would instantly tell you whether you should trust the Captain of the boat or whether you've got yourself a Captain Schettino.
Brings back memories.
18 years ago I got my skipper's license. As part of the exam, which happened on the school yacht, the guy pointed at the life raft, and told me to explain how this gets deployed automatically if the vessel sinks. TBH, I wasn't prepared, but I figured I'd could figure it out just by looking at it. Took me 10 seconds to figure out that life raft was going down with the ship. So I confidently said that it won't get deployed, because it wasn't correctly installed.
The examiner looked incredulous and said that there was no way this could be true. They're always correctly installed. He bent down, looked at the raft, followed the lines with his eyes, and said, "wow, you're right", and gave the teacher (who was along for the test) a piece of his mind. Lucky for me, he forgot to then ask me how it was supposed to be installed.
@Pouty MacPotatohead It won't inflate the raft. The weak link comes off with it, and thus the rope never gets pulled to inflate the raft. Maybe it could float to the surface if positively buoyant though.
@@herbert633 They are slightly positively buoyant. It's how they float out to the end of the painter in the first place.
@@NikkiTheOtter someone will have to reach the closed raft, find the painter and pull it by hand, hoping the raft will not hurt you while it deploys. During the day it might not be an extreme challenge, but at night it will be
Awesome! I've seen these on cruise ships and wondered about them.
Nicely explained. Thanks for the clearing the doubts
nicely explained and visually represented,helped me a lot...!
good information. thanks
Thank you so much for this video 👍
So many new things I learn watching this channel. Awesome!
A little correction for the last animation. Liferaft never afloats in capsule. It opens underwater and only because of it it is possible to break weak link and get afloat
Thank you bro❤️❤️❤️❤️❤️
I love your work! Please do one o steel or metal ships (Pardon my ignorance) vs ships made from wood. If we took a gallion and outfitted it with a shipping ship eng8ne, would it be as efficient, if not more efficient? Thank you for your amazing work friend, and know that you're teaching those who had no interest in sailing but you're making them interested :)
That sounds like an interesting idea. I'll see if I can work it into a video at some point.
@@CasualNavigation thank you so much! I just read shipping ship engine, oh god the ignorance is strong with me lol
I LOVE THIS CHANNEL!!!
If only the Titanic had these.
If only the Titanic had these, then everybody else would be in a lot of danger.
@@ibalrog how?
@@andreaskavak2364 It's a play on words meaning that only the Titanic and no other ship would have these.
@@andreaskavak2364 We learned alot of (painful) lessons from Titanic, if it had not sunk how it did then far more lives may have been lost in a future disaster.
It's so much help more me to learn
I believe there is missing info: the painter line is actually responible for inflating the life-raft. One fully extended (a good 10m or so), it will activate the self-inflation unit inside the life-raft. The pressure inside shells will break the ribbons closing the unit and the raft inflates. It is very hard for a survivor to do all the above, while in the water
2:53
Seems that weak link would be better on the raft end of the painter. That way if the painter gets caught in the rigging or some other obstruction, the raft still releases.
Well, you want the painter for throwing to a rescue vessel or pulling another raft to you once you are using the thing. Painter is the rope to the bowl of the boat for towing and tying to a dock.
@@EwanMarshall Not the one attached to the raft you don't. You're not throwing it to a vessel, it's attached to the raft....
No because the raft would not be left with a painter and make be left un-inflated on the surface...
Great vids! Keep them coming.
Perfect❤️
Im doing well, thank you
people who get the joke will get nothing from me
What a fucking genius idea
This is why I have a velaise life raft. If we need it, we deploy it and hop in. No relying on a bunch of gear on a fully rigged deck.
You can still deploy this manually, that is what the senhouse slip is for, however on a big ship, you don't want to make sure you have released them all manually, and you want the others for their supplies even if you are not directly using them.
I'd like more videos on life rafts and life boats ( the big orange things on cruise ships)
What is in the white barrel? What happens in it when the painter is pulled?
What's in the barrel is an inflatable life raft. Pulling the painter fires the gas canister which inflates the raft. (As I understand it, I am not an expert.)
@@hermitoldguy6312 Pretty accurate. The painter is also left attached to the raft for as a line to pull in the raft when rescued.
I used to crew small sailing ships . We had I think , one , it not been a large ship . But the skipper and owner , was always on about how much the yearly check cost for it.
Really interesting even though I don't sail at all
That's a funny irony, but i actually do an amateur "inspection" of safety equipment on my deck, after placing myself in cabin. (mainly because it gives me a reason to stroll the walks)
@Jay Swarrow very smart to check the safety equipment yourself. I wouldn’t be surprised if you found problems occasionally.
Someone told be those are depthbcharges for submaries. Belived it for a while
We are taught about this by our instructors in s.o.l.a.s. before we are awarded our certificates.
Senhouse slip? Looks like a Pelican hook to me!
Also, I read a report about 15yrs ago by a major P&I club that stated 50% of the life rafts they had inspected in the past year were rigged wrong. (I’m guess it was not actually them do the inspecting, but compiling reports from Port State and Class Society inspections of member ships)
I were wondering if it was perhaps similar to water activating life vests that at least used to use salt charges but for something constantly stored outdoors and in contact with rain and splashing that obviously wouldn't have made much sense
Some life jackets use the same method of operation-not the salt pill. Look at Mustang Survivals Hammer units. I have the Hammer units on my boat, I don’t like the salt “pill” method, due to deployments when not required and periodic salt pill replacement. Yes, all inflatable life jackets require some maintenance.
But how to get inside of that?
They auto inflate and pop out of the plastic shell
Thank you
Cheers Rian
Explain about that color in HRU (yellow and red)
I believe they are for different activation depths, but do check with the units themselves as I am not completely sure
Can you do one with non-weak link system (a,k.a float free arrangement with separate painter and inflation operating line?)
I'm good, thanks! And How r u?
Very good explanation,, can u please do one video on enclosed life boat in details?
I'll add it to my list. There is a lot to cover with lifeboats, so may cover different parts in different videos
@@CasualNavigation Thank you so much for that
Great video, but how do you use these rafts
They auto inflate and pop out of the plastic shell
Is a similar method used to release EPIRBs?
Yes works exactly the same way and a single company (Hammar) makes the vast majority of HRU for both liferafts and EPIRBs.
@@namechamps I wanna say they also make ELTs (or emergency location transmitters) for aircraft
Wait what’s the point of the weak link?
As in, what’s the point of having the painter to hold the raft to the vessel?
It needs to hang onto the painter (rope) for long enough that the canister floating upward pulls on it to inflate the raft, but then it must fail in order for the raft to come to the surface. It'll be engineered to fail at a specific force to achieve this.
Weak links are common where you want things to fail in a predictable way. In gliding, for example, there's always a weak link in the launch cable so that (say) an over-enthusiastic winch driver doesn't rip a chunk out of the glider or snap the cable.
I knew they weren't called float boats for when you sink..
But now I know how they do what they do....
........ let's follow this rabbit hole an see where it goes..
Stupid algorithms.....
I always wonder what would happen if the boat capsized 180 degrees before sinking, or if the boat sank in a shallow water, like 3 meters deep 🤔
1. Let's hope you can release them early enough manually.
2. If the water is so shallow, hopefully enough of the boat raises out of the water.
But yes, I have the same question, how much pressure do these need to release?
How is the weak link work ?
In rough seas what’s to stop big waves washing over the deck from triggering the HRU?
Like he said, an HRU doesn't detect water, only water pressure.
The HRU must sink below the surface (by several meters) in order to release the rafts.
If a raft is positioned at the bow and driven into a very large wave, there's some possibility that a standard HRU could activate. But it takes more than an awash deck - the HRU needs to be solidly buried in a mountain of water.
The risk of a raft sinking with the ship is much greater than the risk of losing a raft to heavy seas. That's why HRUs are required on almost every raft.
Sir plz explain what is difference between liferaft HRU and Epirb HRU?
The actual HRU is the same. The difference just comes from the release mechanism. Liferaft ones cut the link, and epirb ones will cut the case free
Thank you...☺️☺️
@@CasualNavigationsorry you are misinformed HRU (Hydrostatic Release Unit......) EPIRB (Emergency Position Indicating Radio Beacon) so it's not the same
Hi Armadito, the question relates to the differences between the HRUs used in the life raft and on the EPIRB respectively.
@@amavic1 , how does that shoe leather taste.
What are odds of getting to one of does after you boat has gone down. How long would it take? A big cruiser could take a while to go under.
If you've got that kind of time you release it manually before the deck is awash.
Shouldn't the painter be equipped with a manual quick release aswell? If you manually release the raft and inflate it, the painter is still attached to the sinking boot via the weak link. The raft will get pulled under untill the weak link breaks. Or is the weak link breakable by a human pulling on it? It seems that it needs to be strong enough to hold the raft down during a storm, so maybe a person pulling at it won't break it.
The raft isn't being hold by weak link.
The raft is being hold by yellow rope.
The yellow rope is a loop.
The weak link is attached to yellow rope.
The weak link can be design to attached to the ship. But what for? There's no need to move the weak link.
Maybe a human can not, but a inflated raft should, without being pulled under water. But the graphic is wrong. The rope is not only connected to the weak link but also to the HRU. Should be only tired around the upper bar of the weak link.
This dude navals
What are these things ??
Please tell me I'm not the only one worried about the sharp edge cutting through the rope.
The sharp edge is held away from the rope until the safety catch releases and fires the knife into the rope.
wheres the raft part?
1402 Camryn Spur
I believe the painter should be madefast on deck for the reason that if the ship sinks it will not carry the liferaft to the bottom and instead when the raft was release it will float to the surface in the process it will pull the release mechanism of the raft inflating it on the surface. or you can pull the painter until it releases the mechanism to inflate it
You mean to attach the painter directly to a hard point on the deck instead of to the weak link on the HRU? The life raft will never release in that case and will just go down with the ship, even if inflated.
The painter is attached to the raft and is part of the raft after it deploys. If you tie the painter to the deck, then the life raft will be pulled into the depths along with the boat. Then, you are left on the surface with no life raft, and as you run out of energy, you will slowly slip beneath the waves, another life claimed by the cruel, uncaring sea.
I believe many people believe this and temper with the device.
What happens if the water is too shallow to trigger the mechanism?
Then would you need a lifboat? If it's shallow there's likely earth nearby.
Otherwise, if you're really unlucky, the boat would not sink still, since the water is shallow. It'd just hit the bottom, and maybe sink halfway.
Any water with a depth of lower than your height is dangerous to you. People have manage to drown in puddles after all.
@@MrMichkov If the water is so shallow it won't activate the mechanism, then it's so shallow that you can do it yourself.
...Vut are you sinking about?
But How does It get opened?
Painter & weak link.
Parker Landing
Anyone else read that as "how are you?"? 😂
wouldn't it be smarter to release them before it hits the water?
The challenge with increased sensitivity is false detection making it launch in non-emergency situations. If you are a week out and they launch accidentally you wont have life rafts for the week to get back to port to replace/fix them. The video references splashes. The splash can have momentum simulating the force of a few feet of water. If the system is designed for 10s of feet there is no risk of splashes firing them early.
You can release it manually, but the HRU is there in case for some reason while the ship is sinking not all the rafts were released. In that case, after the ship has sunk a certain depth any remaining life rafts will attempt to release and inflate themselves, allowing any survivors in the water to board a raft. The HRU is not designed as the primary launch mechanism, it is designed as a last resort.
Short answer : yes.
But in case there's no time, this ingenious invention, make sure that all of them released after the ship is sinking.
Never allow a Hydrostatic Release Unit to be within close proximity of a Fluxgate Magnetometer. Oh the stories....
life raft ? i always though those were emergency boyance to help a ship sinking lol.
I’m good Hru?
11 to davy jones locker
im good wbu
47844 Melba Mountain
DuBuque Mission
Fay Road
I've seen these things painted shut.
45194 Quitzon Spurs
As we make smarter engineers to design these well laid plans, Murphy is hard at work making even smarter Murphies. And then we are busy making newer and improved fools to defeat the best of well laid plans. The race never ends.
I'm good. Hbu?
"Haych"
Its a big disappointment of how many seamen, supposly having many training courses and many years of experience...still install the HRU wrongly...despite the clearly indicated instructions!
I am tired of finding so many vital mistakes on board ships...
I like ur videos but I am disappointed in ur channel ur channel has insightful information on engineering feet’s that help modern ships be amazing as they are today... yet your channel is named “Casual Navigation” yet it dose not have any videos on how to navigate a ship or boat using any of the navigation tools ( maps, sextant, compass, etc) please make videos on actual navigation, thank you and keep up the awesome short span educational videos.
Beware of chinese copy clone HRU that are not approved, I lost $1000 on those that I could never sell
Horrible design 😳.
Rough sea, ship's going down, but you can't get into your life raft until you are swept away by the sea. You have almost NO chance to swim to your raft.