Carbon Fiber Submarine Implosion: How Many Dives Can It Withstand?
How many dives / pressure cycles can a carbon fiber submarine / submersible / pressure vessel take? How fast does the material weaken by continuous trips to close to it's crush depth / implosion pressure?
We are going to find that out on this video. We made scale model of carbon fiber submarine with similar design and Titan from recent accident. Then we did multiple test dives on our deep sea chamber 10 000 000 and recorded the tests with Chronos 1.4 high speed camera to get maximum amount of data out them.
The carbon fiber was just general use pipe and metal end caps were machined out of steel and then clued to the pipe with two component epoxy glue.
Link to Chronos Cameras www.krontech.ca/
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Do not try this at home!! or at any where else!!
Music Thor's Hammer-Ethan Meixell
Yes, there are certainly many aspects that could be improved to make our model more similar to the Titan design. However, our primary objective was to test carbon fiber as a material in this specific use case. We didn't want to spend additional time trying to exactly replicate the conditions of the accident, particularly since we're a small KZhead channel and our results might not be precise enough to provide insights into the accident itself. If you are interested I could do second video where we test how much stronger the carbon fiber is on holding pressure compared on keeping it out. I have design already for that but I am not sure do I want to use my summer vacation on finding that out :D But maybe after the summer vacation!
Plz do that pressure test as well waiting for that one...thx
Nice!
Carbon fiber uses resin to bind every thing together. So you are relying on RESIN to keep you safe in a deep dive. RESIN Pure madness! If it even worked once; you would have to swap out the hull after every dive past a Certain threshold. Thus making Carbon Fiber more overhead costs Then Steel or some Clad alloy. That this was used at all is insaine.
Enjoy your vacation! I can wait for you to come back recharged and with some good testing ideas. Love your channel!
If you can replicate the hull its going to be amazing. Imagine if the part you used in the video was fully metal, same shape but carbon fiber part of you submarine was also metal and 1 whole part, not glued 3 parts. And then you do carbon fiber coating for the middle hull till it reaches the thickness of outer rings
This is probably one of the most accurate representations of what happened down there. Thank you for keeping it drama free
Even if test conditions were not exact, it just shows how hard it is to build a submarine with the materials they used.
im sorry but no, not only do we NOT know what carbon fibre structure they used, we have no idea on there own test conditions and even if carbon fibre was the fault (that has only been speculated) we still dont even know if it could have been a faulty seal and nothing structural from the Titanium/carbon fibre hull from the sub.
@@123TheCloop you really just put all those words together and thought you sounded intelligent lmaooooo The carbon fiber was expired, carbon fiber is not rated for that depth, the passengers could hear the carbon fiber cracking on previous trips, the CEO is on record showing his disdain for safety and his pride in using expired carbon fiber. The carbon fiber and the CEO were at fault you absolute clown.
@@123TheCloop This demonstration accidentally showed what a leaky seal could do - fill the vessel without crushing it. And the real one is reportedly in pieces, which seems more consistent with an implosion.
Agreed.
These experiments are some of the earliest and first experiments OceanGate should have been running… understanding what you’re working with in model is fundamental to understand what you’re getting yourself into.
Yeah right? There were lots of scale models they could have used. I think he knew at some point it would fail. He didn't want to waste the money to test Titan, knowing it would get destroyed. He was willing to die. In a way he knew it would catapult Oceangate to front page news. He didn't care what the fallout would be to the industry as a whole.. he never cared about others .. which is why he didn't listen to anyone. Those who say " he thought it was safe because he went down every time" don't realize he had a really nihilistic attitude and assumed he would die one day, but doing what he loved. Bringing others down with him is unforgivable. They were dollar signs. That's all. He cared not for life, he cared about being famous for deep-sea exploration. Now he is.
They called up NASA, grabbed material without proceeding through a proper design/test regimen, jury-rigged the rest of the components and shoved occupants into the thing to start ringing up dollars as soon as they could. That the sub lasted as long as it did, is nothing short of incredible.
@@larsvonrinpoche1229 True, true. He'll be studied for decades, if not indefinitely, on what not to do.
Oceanfate was about making money first nothing about safety
@@larsvonrinpoche1229ge cared about his pockets only
This is exactly what I was looking for. Its hard to find a good simulation about this that actually captures the sheer FORCE that water has. Nothing compares to a proper test
It’s not the water that is the force per say, it’s the medium by which force is being applied(gravity in case of titan). Water is very strange, but without velocity or force it’s nothing.
Gravity
FWIW, this doesn’t show one particular major design flaw as it is a scale model facing similar pressure. As I understand it, the actual design called for 8” of CF thickness in the pressure chamber walls. Oceangate got a good deal on old CF material from Boeing. However, they were not able to get enough to make the walls of the pressure chamber that thick. So, the design was changed and thinner walls were used. There is so much questionable information floating around but I am reasonably confident that this is essentially accurate. To change a design using an already questionable material to be even thinner and add an unnecessary feature (viewport) with an insufficient strength rating just really shows their recklessness. I believe that if it was intended to go down only one time that would be bad enough but the pressure cycles really made collapse inevitable even if these items that I’ve mentioned had been addressed. Carbon fiber is too brittle to survive multiple pressure cycles at these pressure levels… especially if insufficient material is used.
@j.griffin VIEWPORT is absolutely necessary. No point diving to the Titanic if you cannot look at it .
Really appreciate the rejection of sensationalism. I think the takeaway for me was the instantaneous nature of runaway failure. It's easy to imagine that a pressure vessel might buckle and groan like Hollywood tends to show. In reality, the moment it goes a tiny bit wrong, it goes all the way wrong immediately.
From what I have gather, it does make noises before giving out, however it also makes sounds during normal operation. However All I have seem so far is going for compression force to bending forces, and the whole thing implodes.
@@youkofoxyI dont think carbon fibre makes sounds. Sure a metal sub can deform a bit before implosion but carbon fibre is like an egg shell. Super strong until it isnt.
Takes 25 milliseconds.
@@Xirpzy the Titan was reported to have made cracking sounds on previous dives.
@@soklottakes far less than that .. 1 to 2 milliseconds which is why it's over long before pain and vision information reach the brain
"The water was able to go in. Which is not optimal for submarines." So true. Kiitos for all the efforts. Very interesting video.
Good thing we have experts to explain these complex concepts. 😁
Kudos
🤣
Reminds me of my high school teacher who told us that if we fall into water, we will get completely wet.
It depends on what part are you talking about. If we're talking about the ballast tanks, it is very optimal for water to be able to get inside or the sub couldn't even sub.
I am always endlessly fascinated by just how FAST implosions happen. Even with the camera slowed down... both explosions and implosions just happen within milliseconds.
You cant realise that it will be gone in a nano second
Faster than the speed of brain processing all those electrochemical impulses. They didn't even realised that they died.
@@mateowag In fairness, nobody ever realizes that they died regardless of cause of death.
@@jonny6702 So a man not beeing able to swim, would not know he was dead, while he was sinking with air in lungs?
@@jonny6702 if ur falling from height ur pretty aware lol or drowning too, theres def a few other means of death ur gonna be aware lol, ur brain dies last in those cases.
You are the only one who actually shows a real implosion and how violent it is, that little piece of material explained a LOT! Thank you for the amazing video!
A lot of people who DIY high pressure stuff don't consider pressure cycling. It's the reason why one-time use helium tanks shouldn't be used as compressor tanks among other reasons.
Could you elaborate on why this is the case with the helium tanks, are they that much weaker than propane tanks? Would the pressure differential be too significant for a helium tank to be used as a compressor, not to withstand the force pushing away from the inside of the tank?
@@gtweak7 single-use helium tanks are made to be filled once then emptied and thrown away. The steel is thinner and lower quality because it needs to withstand only one cycle instead of hundreds + potential buildup of rust in compressor tanks. So even if the pressure is within limits it's not safe.
@@sioux22 Also tanks take way less damage if you cycle them from high pressure to still-kinda-high pressure rather than all the way down to ambient pressure.
@@gtweak7 work hardening lowers the yield strength
@@sioux22 That's not it. The size of helium atoms is so small they can creep into the metal lattices of the tank. This causes all kinds of changes to the properties of the tank material and thus not reliable anymore. Of course pressure cycling is a big one, but helium doesn't even need pressure cycling to saturate the metal lattice in the tank wall. The metals must be recycled and remelted to bake out any impurities.
Honestly its nice to see a content creator approach a subject this delicate with some tact.well done
Unlike certain people on fb relishing in the fact that rich people have died.
@@scuntsIts me, I'm certain people.
@@deletdis6173 delete dis
@@scunts not just rich people, dumb billionaires. Ive been laughing about it for many weeks now.
well lets be real, everyone came here to try to see how they got crushed lol
I'm glad that you show the experiments that DON'T work out, as well as the ones that do. Sometimes the "failures" are just as informative. 👍🏻
I'd be interested in seeing some x-rays of the CF before and after a bunch of pressure cycles to examine fatigue.
Yes, all the micro delam
Oh heck yeah that would be interesting to see. I was wondering if Stockton Rush did any sort of scanning like that of the Titan after hearing cracking noises during multiple trips. He knew the cracking was caused by breaking fibers. Did he even bother to do a thorough check?
@@musicloverchicago437he’s on record as saying a method to scan for damage wasn’t yet invented so no (I’m no expert so I don’t know if there is a reliable way to test the carbon fibre for fatigue)
@@starlightlilly7203 Not true. Very large complex shapes made from carbon fiber used in, for example, aircraft wings, have been scanned. There are human medical imaging devices which are not prohibitively costly that can do a not-ideal-but still-very-helpful job. You would ideally prefer a CT scan, not a simple x-ray, of the tube before and after.
@@mriguy3202 yes I’ve heard about ways we can see internal fatigue in materials through X-rays and other methods but I heard about issues doing the same methods with carbon fibre as it isn’t uniform. Not sure about the ins and outs though, I just know Stockton Rush claimed there was no way to scan the material for fatigue (if true carbon fibre shouldn’t have been used, if false it should’ve been scanned and not just visually inspected). I know there is more than likely a reliable method of testing for fatigue in carbon fibre that wasn’t used to keep costs down
I believe the consistency of the failure point is a testament to how good the quality control is at the company that produced the tubing.
You can see that the tubing has strands in the axial and longitudinal directions. Same with videos I've seen of aircraft fuselage construction which also include at 45 degree angle all to give it strength in different directions. From videos from the titan construction it looks like most if not all of the pattern is in the axial direction.
QA wasn't really the problem. Though they help prevent problems. Would say Engineering problem brought on threw lack of knowledge of Materials. Most people are right Carbon Fiber isn't that great for something like this because of it's lack of flexibility.
@@kamui004 According to the Titan/OceanGate wiki page the tube was constructed of alternating hoop plies, applied wet, and longitudinal pre-preg plies. One video I saw of the construction they were applying at least two layers of hoop with a filament winder. I work in composites and have built vacuum and pressure vessels, filament winding, pre-preg rolled tube (like in this video) and aircraft components. Aircraft wings in particular use 45degree orientation to control aerodynamic torsion loads on the wings. Composites driveshafts and bike frames also use 45degree plies to control torsion. A vacuum vessel is not in torsion, and only needs hoop/circumferential plies to withstand the all round pressure pushing inwards equally all around, and enough longitudinal plies to withstand the ends pushing in towards each other.
@@kamui004 True; however, Titan had a steel tube for its center. What I'm seeing in these videos in a failure point where the end caps and the tubes meet. This glued area appears to be where the leaks and failures are occurring in these tests.
@@Calliber50 The tube that the carbon fiber was wound around was not part of the sub. That was just a mandrel for assembly and removed after curing. Interior shots of the sub show the CF clearly...so the only thing between the crew and ocean was 5" of basically fiberglass resin. The CF windings added little to nothing to the compressive strength of the vessel. One commenter said he'd built vacuum vessels out of CF...which I believe because even with a total vacuum inside (impossible to make) that the exterior pressure is only atmospheric around 15 psi max. Deep in the ocean it's thousands of psi so not even comparable...and the failures seen in this video DO look like what happened.
I think the result with the test sub filling up with water as the glue failed was a telling result and not necessarily a failed test. It shows that bonding two different materials is extremely hard, especially when extreme pressures are applied.
Totally agree. 400bar with different materials is a huge undertaking. If a company like Boeing is still learning with it’s carbon fiber wings after certainly a huge certification process. It is easy to imagine why this solution with carbon fiber was so dangerous at repeated 400 bar rea life tests….the speed and violence of the collapse at “only” 80 bar shows what is at stake
Bonding adhesives to metal surfaces is a very tricky business, as there is very little chemical affinity. A smooth, machined surface also provides less "tooth" for adhesion. Then, there is the issue of gas bubble formation in the adhesive as the monomers combine during curing - even microscopic defects can be catastrophic failure points. The other point to consider is that the composite material is very rigid and brittle, lacking in elasticity. The third aspect of the join is the different thermal expansion properties of the dissimilar materials - not tested here, but very much in play in the deep ocean environment.
the titan had a thin layer of titanium beneath it's carbon fiber cylinder, so its not like glue was what was entirely protecting the pressure vessel as far as i know, like in this model, but yes youre right actually i might be wrong and they mightve just relied entirely on glue
@@chemechAlso take into account when Titan had the titanium end caps bonded to the carbon fibre hull, it was done in an open warehouse with no temperature or dust control, it was done by hand with the kind of squeegees you apply tile adhesive at home⚠️😳😲 I think the carefree nature of safety and risk was very apparent in videos I've watched online of this process!
@@pdtech4524 Wow! Excellent point. David Pogue said it best when he said it seemed like “Macgyverism” was used when building a sub intended to withstand immense pressures.
As mentioned by others, I'm very pleased with how this video was put together; with respect and focus on the engineering aspect of the incident. I hope this video becomes instrumental in the research of deep sea submersible construction and destructive testing. As someone who works in the oil and gas industry, I completely understand how expensive destructive and nondestructive testing can be; however, it is absolutely necessary, mostly when lives are at stake. Once again, thank you for the respectful and professional approach in the making of this video.
What ever so he was right the carbon fiber was a good idea and it could work for 50 dives and all the 99 percent of the brain washed dimwits go along with the you have to have a dive bell for safety. His idea carbon fiber was sound even if you wont accept that anything that go's to those depths no matter how well made will eventually fail. This is your future lean to love it... THREADS
Genuinely a pleasure to see something so well put together that's presented so respectfully.
...I gotta admit, I still wanted him to put in a couple strawberries in there, though. Yes, it's distasteful, but people are curious.
Stockton Rush "must show him respect because he killed multiple people." Donald Trump "Never show him respect because he is Donald Trump." Lol...
@@HorrorUberAlles It isn't distasteful at all. Strawberries are very tasty.
You have, in my opinion, demonstrated that the engineering challenges involved are non-trivial. Looking at this video, I can't begin to estimate how much more data I would need before arriving at a place where I would risk my life. Thank you.
NOt only that but it proves that withg very little time and investment they could have tested scale models of the Titan and used that data to gague the amount of cycle it would be safe for.... Instead of treating your customers like guinea pigs.
I think I would have used a tested design... perhaps out of steel or titanium and not CF
There's probably at least a PhD's worth of research that would need to be done to properly understand the performance of a carbon fibre hull in this application. My guess is that you could never be confident that it could safely undertake another diving cycle despite non-destructive testing.
Especially if the window was only rated to 1300M depth. I think that is where it failed.
OceanGate could have built ten 1/10 or 1/2 scale tubes and cycled them down the Mariana trench 100 times (10km).
This is the first and only experimental demonstration that I have seen of an implosion really applicable in discussions around laminate hulls for subs. Good job!
that and the fact that no-one else made laminate hulls for subs? because no one else was stupid enough to?
There is a 10 year old YT of 2 UK University of Southampton chaps testing C.F. It shows same failures. This was known before Titan.
I've been hoping somebody would create a miniture testing of the Carbon Fiber hull to see if it collapses under high levels of pressure. Props to Hydraulic Press Channel! Thank you!
Was interesting to see the collapse during this demonstration, guessing the air anomaly at the left was the air in the chamber being compressed, similar to ballistics gel cavity ignition?
But it makes you think about how much would the pressure cylinder used here for all these videos deteriorate by all these sudden pressure changed? When stuff implodes inside the pressure chamber, it will introduce a shock wave which may cause quite a lot of stress on this cylincer, its bolts and the viewing window.
To see the ends pop off like that and even the fragments fall out of the groove leaving the caps clean speaks volumes as to the accuracy, chilling and fascinating.
As someone with zero engineering knowledge, this was incredibly informative and understandable. Thank you, subscribed!
Hydraulic Press Channel has now officially done more testing in one day than Stockton Rush did in three years. The lesson is even a small scale model test is better than none at all.
“ yeah but they were testing on non- military aircraft grade carbon fiber.” -Stockton Rush
I don't think that's fair to say. He did have successful dives and it was to that point still experimental
Many people don't realize that the sub didn't fail on its first dive, it had many successful dives. I think the failure was cumulative cycle fatigue. Future subs using that design may need to be limited to 6-8 full depth cycles then relegated to shallow training dives. If a new unit is built it should be unmanned cycle dip tested to full depth until failure to learn the max cycle limit.
@@sprky777 that's exactly what people were warning them about, it wasn't a fully shitty idea but it wasn't tested in any way to understand how it would endure the stress and when it would eventually fail. they found that out in the worst way, which was what ppl were launching warnings about.
Actually they did a lot of testing at a proper institute, but I don't know if they did the cycle fatigue testing. Even metal deep dive subs are usually used once or several times and then retired to the museum
My daughter heard about the situation and I was having trouble explaining it - this video really helped me to show her what can happen! great work - simple explanation of difficult science! Thank you.
As others have already mentioned, this is one of the most accurate representation of what may have happened down there. But just to remind everyone, 80 bars is just a fifth of the pressure that the Titan Sub experienced. In addition to that, that pressure won't change even if the Titan sub already imploded. Cheers mate. Thanks a lot for the representation.
"...that pressure won't change even if the Titan sub already imploded."
@charlesbonkley wow thats something to think about. Thank you for bringing this up
@@charlesbonkley As you can see on the bubbles on the surface of that cyllinder, each time the pressure shifts at around 10 minute mark the bubbles got extra small, almost invisible. Also the bigger the cillinder then more fibers there are, smaller ones. With bigger surface there are much many more points of failure that can develop, more chances for imperfection in surface.
@@charlesbonkley In the test pressure changed by only 2 bars during implosion so what you saw is pretty close to what would really happen 840 meters deep. If all the air in the sub formed a tiny bubble, it would still rise to surface and it would expand as it gets closer to surface, but some of that air would dissolve on the way. All the air in the crew compartment would leave behind a bubble clearly visible to a naked eye. The air would be extremely hot after being compressed so violently and it might create a layer between water and that bubble that prevented them from mixing until air cools down. I'm not an expert on these matters so don't quote me on this.
It's kind of amazing that it lasted as long as it did. This video shows how insanely hard it is to build a tiny version of what they did, and when you see how many corners they cut and how poorly it was inspected prior to use the fact that it made it down and was able to spend over an hour at that depth is honestly kind of remarkable. Unfortunately their fate was sealed as soon as the designs were approved.
Really makes you appreciate how fast the implosion was. It was over before they knew it.
So u hope
@@___meph___4547 that’s what they say yes But I’m just saying, has there been anyone to ever witness an actual implosion under the sea to KNOW for sure? Besides extrapolating surface implosions and experiments such as this? The laws of physics are always “laws” until they not
Except, possibly, for the alarms and their effect on Rush and Nargeolet, the consequent and likely hurried act of dropping weights to ascend(if they did), and the ever increasing crackling sound from the walls all around them... I sure hope none of that happened, but that scenario seems as likely to have happened, as I see it, as the all but blissful exit from this world some seem to assume took place.
@@Rob-gf3pb maybe try not being high while commenting.
@@swampfox946 There would be no "ever increasing crackling sound". Carbon fiber does not expand or shrink like steel, it just shatters once it reach the breaking point.
It was awesome to work with you on this project! I think we went from idea to done in about 8 hours. The results and visuals we got were fantastic and I think much better show what the full scale implosion was like than anything else in the media. It would be interesting to have some more air in the chamber, I think the implosion would occur much faster if the pressure didn't decrease during the implosion.
Great work David
Looking good dude.
Looking stacked dude! Great work!
I'm glad that your expertise contributed to this revealing video, thank you. BTW, I still watch the Epica 'microwave recycling' video - thank you for that and others too! 😁
Wtf has Anne been taking crack or got cancer?
You may have carried out more experimental tests of the compressive strength of carbon fiber than the Oceangate team... Nicely done!
Probably not though.
@@maskddingo1779 Most likely, considering Oceangate blatantly lied with their claims that they researched in collaboration with various companies and experts, all of which have denounced those claims as false.
Well after something failed at a big scale like ocean gate,.nobody is gonna say we made this or that even if they did. It will affect a large organisation such as boeing or nasa...
@@maskddingo1779had they tested it, they would have know its limits
It was already able to do multiple dives before the accident so maybe the material just got fatigued or smthing
Excellent presentation of what a carbon fibre implosion would be like. This is probably the closest example of what'd happened i.e., scrapnels flying and the titanium parts popping out intact.👍
It seems like the edge where the steel meets the carbon fiber might be causing a stress concentration. Also, on the real submarine the end caps were a lot thinner than those. I have a hypothesis that the different elasticity between the carbon fiber and titanium caused shear stress in the glue also.
Thunderf00t agrees
Agreed....They had a narrow flange as a contact point between the endcaps & the Carbon Fiber but just what kind of exotic waterproof glue they used..God only knows... Testing?...You gotta Test This Stuff for extreme ocean depths & temperatures?.... SMH...🙏📿
@@brockashsfrund he thinks that the sub caught a leak, became full of water, sank, and then disassembled, which is not supported by the wreckage. I wouldn't take anything that he said seriously.
They definitely didn’t account for how the different materials react to pressure and fatigue. I agree with that. Different materials , with different density, buoyancy, strength, and going to react differently to immense pressure. This was like taking a fire suit, and standing next to a nuclear bomb.
@@charlessmith3940 Agreed. The only way you can truly understand what the fatigue life and behavior is, especially in a complex joint such as the submarine end caps, is through extensive experiments and testing.
This is exactly what I've been trying to find to understand what implosions actually look like. Very respectful and educational, thank you. Edit: apparently it's misunderstood. In the spirit of keeping my comment tasteful, as he asked us to do, I kept my comment short and to the point. I know what an implosion is, I knew in general what it looked like, etc. I didn't quite have a grasp on the speed of which it happened, or exactly how something would collapse under the pressure.
Basically inwards bomb
It's like sucking the air out of a bag but very very quick
This is better than many such "small scale" tests I've seen, but still doesn't quite get it. Everyone says water is incompressible, but that's not true. At the sorts of pressures here, water will compress by a fraction of a percent. When the pressure vessel fails, the water rushes in at approximately the speed of sound in water... ~1500m/s. In the ocean (or a big enough test chamber), the entire volume of the failed pressure vessel is filled by that process which is very violent... the water is heavy and moving quite fast. But these small test chambers just don't hold enough volume of water for that. BTW: The bubble that forms on their window in the first test is from cavitation... The momentum of the water rushing into the broken pressure vessel creates a vacuum on the other end (the chamber wall). In open ocean, that wouldn't happen because there is plenty more water expanding into that space.
@@travcollier Either way, those poor devils who died would have felt nothing as their bodies literally shattered into many pieces at the moment of collapse. RIP to the families that lost their loved ones.
no you came here to know what the titan sub implosion would have looked like. be honest.
Excellent video As a certified pressure vessel and boiler welder I know that there's materials that can take repeated amounts of pressure and they're fine and there's materials that can take a high amount of pressure one time When I was building pressure vessels for a living If the operating pressure was 100 psi The test pressure was 500 PSI
Had an air system I built for a company straight up detonate the compressor piping off the walls of the machine shop. So I get called in to look over damage , see what went wrong. For context , we were given an aluminum pipe system out of France. Had to sit through videos on fittings and installation. So , max operating pressure marked on pipe was 120 psi . So , we chose to incrementally test til we reached 110 psi , as the client need maximum pressure for 1" drive tools. Everything is installed , and goes into service . 4 months later , I get the call of the detonation. I walk in to the shop and see , section of pipe and all surrounding spray foam insulation gone . Wild . The shop guy had saved me the one fragment , the whole section of pipe . It was squiggly ripped from one end to the other . So , next step , test compressor . I want to see if it's been "adjusted " or mysteriously malfunctioned. I isolate compressor and kick it on. It clears 110 , then 115 , then 120 , 125 , 130 , 135 . I stop the compressor. I start closely looking over the pressure switches, with site management next to me. We both notice this very dust covered machine has nearly no dust on compressors' high low points box . I guess it a magical dust and grime repellent. Conclusion, aluminum pipe really does mean max pressure for whatever is stamped on it , overseas. I think the shop hand thought it was like good old iron pipe systems, so they felt like they could crank it up to speed up production . The only thing it sped up was everyone's bowels that day .
@@texasslingleadsomtingwong8751 just like everything else from France....
@@texasslingleadsomtingwong8751Aluminium has a limited fatigue life.
Finally someone shows a REAL demonstration instead of making up animated "I think it was this way" explanations. This is a great channel. It's a simple test, but shows so much.
Really a delight to see something so well put together that's displayed so consciously.
I've had such a difficult time visualizing what an implosion at depth would actually look like and this was extremely helpful.
Also how fast it happens. The occupants were dead in one thousandths of a second
If that had been using nearly ninety hours of oxygen for five persons when everything rapidly imploded, you would get a vaporizing explosion from instantaneous ignition of many hydrocarbons inside what now would strictly be only a combustion chamber.
@@raneads1458 way too much presure, it just squishes everything in a microsecond, any gas would stay compressed. Oxygen tanks are at 2000 psi, the Titanic depth gives 5600 psi
The titan failure would be much more dramatic. In this system once the carbon fiber tube begins to fail the applied pressure will quickly fall off due to the limited volume of pressurized water. This is a consequence of the very low compressibility of water compared to the highly compressibility of the air inside the vessel. In the Titan case there is a huge volume of high pressure water pressing in on the vessel. The pressure fall off in the surrounding water will be negligible as the vessel begins to fail.
This is it! Hollywood was not far off
I was so hoping you would do this, I just watched the top 10 shots with the chamber including the mini submarine. Love this channel!
This is probably the most requested video ever so it was nice to get it done
Can you make a carbon fiber sphere to demonstrate the difference between a tube and a sphere under pressure?
@@HydraulicPressChannel Please make more of these. Millions of people want to see what happened to the submersible. Even more pressure.
Thank you for taking the time to do this. Very professional and informative.
I like to be able to fully understand how things work and this is a great example. Thank you!
It's insane how fast the implossion happens. You read about this in comments and articles and see it on various simulations that popped after accident but seeing it first hand is almost nerve wracking. Thanks for doing it.
And we are viewing it on slow mo too.
Yeah, and imagine thousands of gallons rushing in at supersonic speeds like we see in this video. It really captures the ferocity of an implosion under those pressures. By almost any human measure, the void is filled instantly with water pressed down with the weight of all the water above.
At not even a quarter of the depth! So its even more quick and violent!
~3ms, even faster than I thought
It's an explosion in reverse, literally.
former submariner that has designed scuba regulators and valves , so worked with pressure. Your design captured the carbon fiber hull better than Rush's which was simply glued on the flange (which "look" like less overhang than yours in scale) from Ti caps which would have had much more flex during the dive from pressure than yours while also experiencing dissimilar material thermal expansions and contractions (always) making the join a spot of considerable carbon fiber delamination and micro cracking in the resin.
You make a good point about the dissimilar thermal expansion coefficients of the CF vs. the titanium. Too late now, but Ocean Gate should have built a large pressure vessel in which they could cycle test their sub to the pressure depth of the Titanic. If they had, they could also have varied the temperature of the water in the test chamber.
@@rodneybrockethe best way to test their sub would have been to dive it with no one in it many times to the Titanic. You can’t beat the real thing for testing.
@@KevinPriceproblem is no amount of testing will do anything if no data is collected. From what I got, Crush only had acoustic sensors which I wouldn't trust for a small Arduino sensor let alone seacraft, and dismissed engineers telling those were woefully inadequate. Pressure or no pressure, if you can hear or notice any degree of failure you are already beyond the point of no return. Wish one of these test subs failed so they had to explain in toddler terms how the craft collapsed faster than the signal from the sensor could reach the science data collector.
Thank you for providing insight into something which is hard to visualize, and also for keeping it technical and approaching the subject with the respect required at this time.
Thank you for all the hard work and determination in making this. Very telling of what happened....
Looks like the carbon fiber tube you used was wrapped diagonally at a 45 degree angles, all their wraps were parallel, which would be much weaker and much more likely to suffer flex degradation. We know this from tire designs, angled wrapping in a tire last way more heat cycles than parallel wrapped wires. Great video!
Good catch
Ohhhh sssstfu. You don’t know
He would of been just as well off to take that spool of carbon he stole from Boeing's junkyard and dip it resin, cap with Titanium ends...bobs your uncle😅
Which just goes to show how shoddy the Sub was, they didn't even lay the carbon fiber properly.
Except that's bs, their wrapping wasn't parallel
There is also very large temperature changes for each dive that could have had a big impact on the hull degrading/ weakening.
True. And plastics/resins have larger thermal expansión coefficient than metals. That could be an issue.
@federicolopezbervejillo7995 wrong. It's the opposite.
Good point
Also if you scale down the vessel, the difference in thermal expansion rates between diff materials makes less difference. So between that and it being so much harder to make large, thick pieces of carbon fibre without defects probably explains why their test didn't show any change in crush depth after cycling.
Below 30m the temperature (the bathythermal layer) is a constant approx 4c. Water is most dense at approx 4c. If the surface air temperature was between 10c and 20c and water temperature is about 6c off the Labrador coast then the main thermal shock would be at point of entry into the sea. Furthermore below 30m, they would need some form of heat source to prevent hypothermia at depth. This would create a thermal differential effect where the outside of the carbon fibre is contracting and inside is constant. Possible delaminating could occur.
I love your channel!!! Found it because of this tragic event and have watched many of your videos. Great job on the work that you do.
BRAVO, HPC! This is *the* most scientific example of anything you've ever done, and the best representation on KZhead of the problems associated with cycling of CF vacuum vessels. You are doing wonderful work.
no cycling issues were observed. the test literally showed ZERO reduction in strength through repeated cycling of CF vacuum vessels
The most basic safety testing for pressure systems usually involved applying 2x or 3x their rating for a set period. Pressure cycling is probably a good addition to that!
I watched some making of videos for deep ocean submarines and those did testing only 20% over the dive depth. For hydraulic etc. something like 400% is even common safety margin.
i dont think that's for lack of trying on the limiting factor, there arent really any facilities that could do 2x
@@Taygetea There is also the point that normal hydraulics systems are far more likely to see abuse and less stringent maintenance and inspection over their lifetimes than something like a professionally operated deep submersible vehicle so you probably want wider safety margins to protect the public in many instances.
@@HydraulicPressChannel 👍👍
The DSV Alvin is designed for 6.5km and tested to 8km (Grumman has a test chamber they put the entire submersible in). Titan was never pressure tested but was supposed to be designed for 4km and failed at 3.8km.
i have a lot of respect for you guys. you did this video in the best, most dignified way possible
Great job, very interesting to see how the carbon fiber reacted to the different pressures and how it ultimately failed. Keep up the good work. Your videos are very interesting and informative.
Thank you for testing this kind of construction. That was a very good demonstration of a pressure failure and implosion. Very well done, thanks.
The fact that your guys vessel pops at the same depth or same bar representation is astounding. You may be able to give the family's some comfort in knowing it was swift and there was no suffering thank you guys for providing good science as always.
Thousands of a second between "normal" and imploded
@@ShadowsDML Literally quicker than the blink of an eye
It would have imploded at the speed of sound in water, 1500 m/s, so it would have happened in less than 2 milliseconds and no one in the sub would have seen it coming. It would have been instantaneous and painless.
This was only 80 bar of pressure, the pressure at the depth of the titanic is 397 bar.........
@@mtheory85 They knew it was comming. Hul must have cracled pretty loudly before it finally gave in. Im pretty sure the CEO tried to calm everyone down, but im sure as hell there was panic and terror before the lights went off.
This is exactly the type of video I was expecting to see, but so far no one, except you hade made one. Thank you for the spared tame and the great effort you've put into it!
There actually a 7 to 13 years old video on KZhead, where a bunch of brits did a similar test; but built closer to the titan sub with a removable end cap to show that the carbon fiber filled with water
@@prototypedrakon9899 yes!! i found that one too
Thanks for your careful and compassion take on this issue…
Really good to see some hands-on experiments to try explain the pressure effects on different hull materials and dive cycles. I guess one day we will eventually know what exactly happened thanks to this kind of work. Keep it up!
no cycling issues were observed. the test literally showed ZERO reduction in strength through repeated cycling of CF vacuum vessels
I really appreciate the professionalism and ingenuity this channel shows
This is good science…well executed, worth a watch by structural engineers! Thank you!
Thank you!
That amazed me just how fast that went from being structurally sound to collapse. Great demonstration 👍
Thanks so much for this, really helpful in the understanding of what happened, love all your videos! Great job!
Sir, I say kudos to you- I saw how the views spiked on your submarine pressure test video after the Titan was lost, and thought to myself, "He's probably looking at the views on this, and wanting to do something more accurate!". This is great and very instructive as to what might have happened, and you were the best person to do that for the KZhead community. Great job folks!
Thats actually a really good simulation. Most test setups won't result in the pulsing of the implosion that happens in the ocean, but your setup managed to simulate that really well.
From the looks of it, the carbon fiber tube in this test might have had more (relative) strength than the actual sub. The cf tube in this test had fibers going in multiple directions, where as the OceanGate video shows only one direction of fibers. That makes the tube used in the test (at least in my opinion) more resistant to shearing forces.
true
@@ReneSchickbauer i was about comment the same about the orientation of the fibers. probably someone could make test samples with fibers in single direction for Lauri for a second round of tests.
@@ReneSchickbauer Yes and the Titan/tube less resistant to a lateral force with the lack of weave and only wound in a circumference.
it tells you alot more then you think if u use math too scale it up u realize going to the exact same depth you built your sub to max go to is dumb cause thats the depth it implodes they were rating their sub for 4000 m they constantly went to 3800m so obviously they would implode sooner or later
this simulation is done very well. very thought out and i feel it sheds some light on to carbon fibers ability to withstand extreme pressure cycles. bravo
Incredible set of runs. There are a couple big differences between the tests and the sub. They were submerged for *hours* which may have given more time/opportunity for water intrusion than quicker cycling. The temps were also significantly different at those depths which may have made the material more brittle. Combined with the submersion time, maybe that's part of it.
I believe the sub had also completed at least 100 dives prior to it's disaster (although I think the fatigue would still show it half that time if it's there?)
@@mehere8038 its actually 10,the fail point was the 11th
Your first sub compression video was really good. I saw a bunch of comments asking for you to do the same experiment with carbon fiber. I was really hoping you would and I'm surprised you were able to do it so quick. Very good video. Thank you for posting this!
We appreciate the empathy you showed towards the situation while also showing us the science behind it!
@@sirwinstonchurchill2052 well I appreciated the empathy.
Impressive work! Very insightful and professional 👏🏼👏🏼👏🏼 let’s hope those who are in the submarine business watch this vid and learn from it. Can’t believe how fast the implosion is even when replayed at slow-mo!
Very interesting. Definitely shows just hiw hard it can be to get a good glue joint between carbon fiber and an end cap for instance.
It was chilling and heartbraking to watch the implosion, but this is the best representation I’ve seen of this unfortunate event. You did amazing job, thank you for doing this experiment!
It was fun to watch the implosion. No empathy for billionaires while millions of people suffer in poverty every day! As long as there is poverty, you *can't* be a billionaire and a good human at the same time.
@@blinking_dodo You sound like the nazis bro. Take a deep breathe
It was a small model in a pressure tube. Stop being so dramatic.
@@blinking_dodo agree with you mostly. But you cant be a millionaire and complete what some great billionaires have achieved. Most are shit tho and only want money. I dont agree with the thought of anyone losing their life as entertaining tho.
Don’t be an ignoramus. Good people are also empathetic. Something you obviously aren’t.
5:20 That was a cavitation. A vacuum bubble caused when all the water moved into where the chamber was when it imploded. The water all shifted away until there was no more water to shift. Dangerous for materials and if your chamber window breaks, that's why.
We always stay clear of the windows when imploding stuff because of this. But that been said they are pretty strong. Manufacturer have promotional video where they first shoot these with handgun and then test the burst pressure and it still does about twice the rated depth :D
I don't think that was cavitation. It was most likely just a microscopic bubble on the surface of the glass that rapidly expanded when the pressure dropped
@@abrasivepasteyeah I think it was most likely a mix of the two. A small bubble under that much pressure would be impossible to see as it would be well below the size of a single pixel on the camera. It's rapid expansion would carry inertia past the point of "equalising" its pressure so maybe some condensation of the air within the bubble got involved too. But hey, what do I know I'm just a welder haha.
If I remember correctly, cavitation is process of erossion on propeller blades because of the speed of those proppellers it creates sub-pressure behind blade that creates bubbles of evaporating water hitting the blades. Same can happend in pipline if speed of fluid is moving fast, evaporation could happend and could damage the pipes. In this case, water is pushing air bubble that heats up to very high temperature and in the moment evaporates water, creating explosion after implosion. I could be wrong.
@@abrasivepaste I think you are looking at the same way as I do, only it may not be a bubble. Under pressure a gas will go into solution and not be a bubble any more. Releasing the pressure causes the gas to come out of solution. Similar to opening a bottle of soda. It is also a factor that divers must consider.
Wow, love your shows, when I first heard of the Ocean Gate submarine lost on the dive, and they mentioned a carbon fibre hull, my first thought was OMG. Your implosion test, and a lot of the Engineers in the sub community out there show CF, ain't ready for deep dives just yet.
The first video that actually shows the carbon fiber implosion. Congrats on being the first to depict it accurately.
Great job. You kept the unnecessary sensationalism and fluff out. You are a model for all other youtubers. Keep up the great work.
Finland
This was really interesting! Especially how the second test-to-failure resulted in the caps looking basically like the wreckage we saw from Titan (pretty much intact, with little to no remainder of the carbon fiber attached), which kind of goes against the somewhat popular idea that that result means the adhesive was what failed - The video very clearly shows the carbon fiber failing, and has similar results. It's also interesting to note that despite carbon fiber's tendency to shatter when it fails, a good amount of the tube was left in one piece after the failure - Perhaps a small defect in the fiber led to one side failing first, and the other side could hold together even though it separated from the ends. Of course, a test at 80 bar with a scale model in a relatively small chamber doesn't necessarily have much bearing on exactly how things looked for Titan failing at about 300 bar, but it's educational to compare the wreckage of both models as validation that the test is somewhat accurate - And it's an excellent visual demonstration of how sudden and violent even the low-scale implosion is. It's interesting how the carbon fiber didn't seem to degrade with pressure cycles, though. That's hardly expected - I wonder if the first tube was built weaker, and the last tube would have failed organically at perhaps 100 bar if not for the cycles. Of course, it's difficult to get consistency unless you have a really precise technique to construct them - And as you noted, that's really difficult (and given videos of the Titan's construction, perhaps not any easier for OceanGate).
The other thing to consider, this was a relatively thin carbon fiber tube compared to the 5 inch thick tube used on the Titan. The much thicker piece having significantly more area for flaws to happen during manufacture.
I'll have to watch the OceanGate Titan sub's construction videos again. I'm not sure how the titanium end cap was configured. But it looks like there was just an external lip but no internal lip. In any case, you see the folks using putty knives to manually spread glue on the carbon fiber cloth as they wrap it and joining the titanium ends. Therefore it is highly probable the glue application was uneven. Besides who thinks glue is a high pressure material?
@@Melanie16040I think someone in the earlier comments said we have no way to measure any micro delamination of CF so figuring out expected fail points is difficult, in addition to manufacturing flaws.
@@zedhiro6131 Not sure that is the case. I suspect either Xray or Ultrasound would be able to inspect such things.
If you go to a NASCAR race and someone hits the wall, watch what happens before they resume the race. The race officials go out to the accident site and literally crawl on their knees. They're looking for any shards of carbon fiber that could have broken off the race cars. It is sharp when it breaks up and can easily slice open a tire at 190 mph. In fact, accidents have happened because of failures to clean up the track properly. After one too many crashes, many racing organizations made it a requirement to search the track and pick up any pieces of carbon fiber before the race can continue.
very professionally done and fully disclosed experimentation.
Thank you for testing this. It was very educational.
Looks like your carbon fiber is wrapped properly in varying directions. This was not the case of the sub. I wonder how it would react to cycling when only wound one direction. Also to note scale is a thing and smaller items tend to be stronger and experience less fatigue than full scale, definitely aren't going to really see fatigue to it's fullest without a larger scale. The fiber at scale if you matched the mini to large would be like ropes in size comparison thickness. Thanks great video, really shines a light on the wreckage, and silences alot of internet engineers with real engineering lol.
Even though carbon fiber is wrapped properly in test, we see how fractures go in parallel with fibers. So when delamination starts it just keeps ripping on unstopped.
The Titan was also taken to 90% of design pressure on every dive. The hull was designed for 4km and the Titanic is at 3.8km.
Agreed, a proper scale would have scaled the thickness of the fiber cloth and kept the number of layers.
@@dgholstein issue is you can't easily scale the tickness of the cloth/strands.. the sub used normal cloth, so to scale it down to such an extent would require nanotechnology
@@alexnicolaou3579 Of course, the limit of scale tests is how much you can scale the cloth, which wouldn't be much. Their test is interesting and clever, but ultimately not a real, scaled representation.
As someone who has been crushing things for so many years, you are very qualified to demonstrate this phenomenon. Thanks for a very timely science and engineering lesson.
You did a great job engineering the test and recording data. Thank you for the time you invested in the experiment. Spencer, Waxahachie, TX
Ty for the video and being respectful about it. Very educational
Very interesting. Just seeing the wreckage they brought up makes me suspect that your tests will be fairly close to what happened (the end caps looked pretty intact and clean, from what the news showed) Thank you for putting in the work, and being respectful about it.
Well yeah... they were made of titanium. The material that the rest of the pressure vessel should had been constructed from. Titanium is leaps and bounds more resilient and stronger than carbon fiber. There is also the fact the end caps were essentially attached to mounting rings that were secured to the carbon fiber with glue. The fact the Titan survived one dive much less 3 or 4 was simple luck.
NOT EVEN CLOSE!
@@GamerLoggosi mean, science is taking risks, but they should have tested it thoroughly before sending people down
@@dassault7618mal
@@dassault7618 Id say science is about taking calculated risks. You factor in every variable you can and look at the result math shows you. This is the basic scientific method. You theory craft, you test and verify. You dont go "Eh... that should work. Lets put living people in there and try it out." Which is exactly what he did.
I really like the conclusion you have at around 12:00. It's exactly what many people don't understand about science, especially on youtube. Experiments and it's data always needs to be seen in context. And although your experiment might not be the most accurate to simulate the tragedy that happened, it's just like you say "that's the data we got". Even though it might be flawed in many ways, it's still data that can be seen in a scienctific senese and adds a small piece that helps drawing the whole picture. So thank you for your effort to shine light on what might have happened at this incident. And thank you for doing it in the respectful manner you did!
If only modern science were like this. It often seems to start with the data they want to find, and then companies fund the studies to go looking for it. Or the data is blown way out of proportion, like current climate and covid "science."
@@chickenmuffinWould I be right in guessing you have no professional scientific qualifications?
Funny how you use scientific rigor as a pretext to deny any science you're uncomfortable with, Sean. With regards to climate science, do you understand the explanation given and can you cohesibely explain why it's wrong?
@@chickenmuffin Billions will get infected now without knowing or ignoring it. Billions will die later without knowing it now or ignoring it. What is your base science claiming that?
@SeanPerrin The fact that you say "covid" and "climate" science shows you do t actually know what you're talking about at all but so sure in rejecting it. There is no such thing as covid science or climate science. Learn the fields,gather knowledge and do the actual work.
Fantastic study and conclusions. What you guys do on this channel is amazing and very much makes KZhead a richer resource. My experience with carbon fiber is with uses in different kinds of tensile loads. Failures did occur under testing, and in those cases it was down to heat or age. degradation. A company i worked for made high speed rotors, where a carbon fiber ring was used to contain magnets at design speeds of up to 60k rpm. I've also done quite a bit of mountain biking with an old carbon alloy frame. The rotor blew up in cyclic testing under 100 degree heat and overspeed conditions. It was under massive force. A bike like mine failed, after a few years, but it was the adhesive gluing the tubes to the alloy lugs that failed, not the carbon itself. I cannot imagine it taking nearly the same punishment in compression, given what i have seen here, so thank you very much. My respects go out to the families of those poor souls.
Best example I’ve seen of carbon fiber under pressure. Thx for sharing results! 👍🏼
I think this is the best practical demonstration of the vessel construction on KZhead. The glued flange seems an area for further investigation as does the basic carbon fibre tube. Well done.
I have never found a glue that is anywhere near as strong as metal. I don't see how they would be able to get a bond strong enough to withstand 6,000 PSI
@@Bryan-Hensley especially given that chemistry, especially organic chemistry gets wonky at such pressures. That's an ongoing field of research, with applications far beyond oceanic exploration. Hell, in the mantle, with its absurd pressures, they've found that some novel phases of ice can exist. Frankly, the technology is surprisingly mature. We'd not be having this discussion at all had Rush done the sane thing and made a bunch of ROV's to explore the technology properly, with full analysis after each dive.
@@Bryan-Hensleyfor destructive testing I had a shop use 10000 psi rated glue. Trying to rip metal off of metal
@@dylanwilliams9860 video?
@@Bryan-Hensley What would be the point of glue under extreme compression forces from the outside? Apply enough pressure and theoretically, the thing could be kept intact without the glue... no?
One thing that might be interesting to think about - a full-sized submarine’s hull has a much more shallow curvature than a small cylinder. Shallower curvatures are less rigid and more prone to deflection under load, which over multiple loading cycles is more likely to cause delamination or other modes of failure. You could test something similar by putting a flat sheet of CF in the press (since a flat sheet approximates a small piece of a low-curvature surface) and loading it at something below it’s failure point repeatedly to see what happens to it
Hoop stress is indeed dependent of the vessel's diameter.
checks out
what? do you know how circle work?
That "should" just scale with the wall thickness though.
I think the main problem with scaling it down is going to be the fiber size.
You handled a very delicate and raw situation very well
That was beautiful ( the experiment presentation ) Thank you. Those guys really did not felt a thing
I’ve loved this channel for a long time, but this is one of the best videos you’ve done. I appreciate both the engineering insight and the respect for those who lost their lives. I especially appreciate the call to action for us, the fans: don’t be distasteful.
A result is a result.....that's science. Great video, I'm glad you took the time to put this together. I think the KZhead community will appreciate your efforts to shed some light on this topic.
Holy shit! That is probably the most accurate representation on what happened down there. It would be more amazing if you get the slowmo guys to record this so that we can see further the implosion.
Thank you for taking the time and research and cost for making this video when you actually see the implosion and how fast it happens will give relief to the families they never suffered was blink off a eye
Very well and respectfully done! I've been very interested in this concept as well since first hearing this and it's great to see you test it out and see how it works. Love your channel, keep up the awesome crushing!
Coming from someone who has studied many aspects of the titanic wreck and disaster I commend you guys for handling this professionally. I was wondering when you guys would pressure test carbon fiber and it’s implosion charictaristics. Good job guys! The titan disaster has been mishandled among social media greatly and I believe you guys have the best representation of what actually happened.
Why so much attention and respect for the rich guys but the hundreds of lives of the boat that shank barely has any attention.
lol "... someone who has studied many aspects of the titanic wreck and disaster ..." - so you've read twitter posts and watched youtube videos :D does not make you a scholar my man :D
@teresashinkansen9402 Well, we know why overloaded boats sink. The c real tragedy there was that the Coast Guards said it looked like they were moving toward their goal, also because they refused rescue, probably because they wanted to be in territorial waters rather than international waters, (for asylum) goals. Sad situation to refuse rescue that overloaded.
@@teresashinkansen9402 That has nothing to do with this channel, keep your complaints for elsewhere please
@@andrewchambers8097 Im not talking about the channel but the comment i replied to. Why I should keep my complaints? cant call out moral hypocrisy?
Thank you! You did a wonderful job!
I think that this is the neatest thing I've watched all year so far...awesome job yall.
It's a sad thing, but I like the attitude with which you approach the subject matter. People are interested in knowing more about what may have happened to the Titan, and that you put respect for the gravity of the issue up front is great.
Thanks for this. My children have been fascinated by this disaster and it’s kind of hard explaining implosions to them. Explosions they understand perfectly well. But this really shows well the whole concept, especially the speed.
Hi Peter, I’ve had the same issue with my son too- this channel has been awesome for that😊
Not sure that’s healthy . I try and avoid that with my kids . That’s how this generation is doomed up .
@@kelvinfannon8416 They’re 14 and 10. They’ve probably already seen worse at school.
@@Peter_Morris that’s the problem . Kids are not allowed to be kids anymore . 10 years old and trying to explain a submersible disaster 😬. When I was 10 I played with a ball and racket during Wimbledon
Excellent case study for the engineering students! This will definitely be included in the new textbook versions.
It was a beautiful and successful test. Thank you for explaining, and giving us some education of what happens to carbon fiber in an implosion.
Extremely informative for us lay-men, and your presentation was very sensitive to the circumstances and in the best possible taste. Thank you!
If you do more of this type testing, putting a scale of parallel lines on the bracket holding the tube you would be able to see how much the tube compresses before failure and during the "cycling" tests. Really interesting "backyard" testing on this. Well done! There are SO many variables when working with extreme pressures. Very difficult to duplicate all of them in a test scenario.
That's a very good idea. I think I'd be inclined to do something like a grid pattern if possible. It may have been an optical illusion, but to me it looked like the cylinder was compressing in on the ends more than in the middle. A grid would show compression both end to end and across the diameter.
A grid on the item under test would definitely highlight any elasticity in the material(s) and the direction they were acting.
You guys are always amazing. You did this in the most tasteful way you could. I believe that tests like these, either done on KZhead or in a lab setting is what prevents accidents. Well done guys.
This was very interesting. Thank you for taking the time to make it.
Listen, bro. You did a great job on the fly. Obviously, there would be a lot of factors that would go into making the model to exact scale. You did the best you could with what you had and I think it was the best cyclical fatigue test I’ve seen on KZhead so far. The apoxy might have been a bit weak. Great video