※This video does NOT include any paid promotion※ ※ 위 영상은 유료광고를 포함하지 않습니다 ※ 📦 제품문의(Product Inquiries): www.tongyangphc.com/main.htm (동양파일) 🎬 촬영문의(Filming Inquiries): factorymonster2021@gmail.com -We film for the company who are proud of showing how their products are made. -팩토리몬은 제품에 자신있는 소상공인 분들과 중소기업을 대상으로 무료촬영을 진행합니다. Copyrightⓒ 2021. Factory Monster. All Rights Reserved.
Thumbs up for shy worker being blurred out. In a time where privacy is gone I do appreciate you taking the time to blurring out a person who did not want to be on camera. And a shout-out to all the people working factory jobs. One of the hardest work environments there is no matter what part of the world you live in. If politicians were 1/1000th as hard working as you, the world would be flawless.
@@maxpayne82 сам голову ломаю. Либо на этапе, когда её помещали для кручения, после засыпки бетона. Был момент, что рабочий закручивал какой-то стержень...короче не знаю))
@@maxpayne82 ВНУТРИ СОВЕРШЕННО РОВНАЯ ПУСТОТА ОТ ТОГО ЧТО ФОРМА ВРАЩАЕТСЯ, НА ВЫСОКОЙ СКОРОСТИ , И БЕТОН ЗА СЧЁТ ЦЕНТРОБЕЖНОЙ СИЛЫ РАСПРЕДЕЛЯЕТСЯ РАВНОМЕРНО ВНУТРИ ПО СТЕНКАМ ФОРМЫ
Incredibly complex process to build high strength reinforced concrete piles. The video editor has done remarkable job by covering each stage of this precise process. 👌👌👍👍
Re: your questions during the video The first object they were securing to the steel cage was the baseplate. This is the "top" of the piling, as the piling will be sunk into the ground. The steel building will be bolted and possibly also welded to these baseplates. The steaming helps the concrete cure faster. It hardens better, faster this way. Thanks for uploading this video; nobody will ever see those pilings when they are in use but it is nice to know what the roots of your high-rise look like.
That baseplate and later on at the 5:15 mark are also probably part of pre-tensioning the reinforcing bar. To add to the steaming part, it's done after the concrete has had enough time in the centrifugal tumblers (my name, don't know the official name) to set up enough that the walls don't collapse under gravity. No "massaging" is taking place ;']
Less watewr better for the lasting concrete.Water too much dilutes chemical process and make weak concrete ans above that when it dry it shrinks and cracks which is not good.
15 million views...8 days. Actually restores faith in humanity that so many appreciate good workmanship, organized factories, good productivity. Great video!!!!
The steam curing is probably needed for strength. Concrete always cracks as it cures - there's no way to completely stop ALL cracking. If it develops large cracks, the concrete will be weak, but if it only develops micro cracks that you can't even see, it will be MUCH stronger. One of the ways you can minimize cracking is by keeping the concrete wet while it cures. That's why when they pour concrete driveways, it's best to keep misting water on them for a day or two. It will increase the strength of the concrete tremendously. Another way to minimize cracking is to keep it the same temperature all over the concrete. And since the center will get quite hot (concrete makes its own heat as it cures), they use heat to keep the outside from cooling off too quickly. And what is hot AND wet? Steam.
Concrete cures the more its moist. its a process called hydration and it happens over time. concrete gains its full compressive strength over months. The steam helps penetrate the micro grains of the concrete compared to letting diffusion to the work, which takes longer i guess.
Not really, it's a chemical reaction with the limestone inside the concrete, where if you grind up limestone, bake it, then get it wet again, it hardens up greatly, and it will just keep getting harder the more and more it's exposed to water, with diminishing returns granted
job looks very dangerous. easy for a tension cable or support to fail and you're toast or seriously injured. glad i don't work in this environment. jobs like roofer, fisherman, logging, steel work, construction, farming, etc. are too dangerous to life or limb. not for me at all. lol. but glad someone is willing to take the risk so I can live to 90 enjoying shopping, travel, restaurants with friends and family and pursuing leisure, exercise, hobbies. there's a job for all ranges of abilities and temperaments.
1. 자막 귀엽다 2. 용접이 너무 빠르게 회전하길래 대충 용접하는 대신 용접점 많은 양빨로 내구성 지키는갑다 싶었는데 한쪽 잡고 들어도 안뜯기고 콘크리트 저래부어도 안뜯기는거 보면 신기하네 용접 ㄹㅇ 잘된듯 3. 콘크리트 저렇게 입자 굵은 상태로 들이붓는거 첨봤는데 원심력만으로 저렇게 매끈하게 다져지는구나
The plate and the bolts into the endplate at about the 2:20 mark serve dual purpose. It helps hold the rebar steel pattern in place, and it looks like it pulls it into tension. The "P" in PHC stands for pre-tensioned, which is where you pull the steel before casting the concrete around it, and it essentially makes the concrete "tighter". This has to do with the relative strength differences concrete has when it is pulled vs. when it is pressed. The oil is formally called a "form release agent", which really does the same thing oil in a cake pan does. Steam is used to cure this concrete, I'm going to guess because it is hot and wet. Concrete needs a lot of water to cure (harden), and a high-strength concrete has a lot of cement, and therefore needs a lot of water. This is a chemical reaction, so if you write it out, there's no water in the end result. Keeping it hot and saturated speeds up the reaction by giving it plenty of reaction material and energy. I'm shocked they're hollow in the middle, which was a surprise after they spun the cylinder. I normally don't work with PHC piles, and spinning concrete is usually not recommended because you can separate the components and end up with uneven distribution. It's quite a fast speed, so I'm guessing the aggregate mix has to be very uniform to avoid this problem. Thank you for posting, this has been very interesting to me.
Kevin C Yes you can bet they have worked on every aspect of their concrete mix. You bring up a good point of the different materials in the concrete can't separate when it's spinning and have to stay properly mixed. Not easy to do I imagine.
Kevin C. Well commented! As far as spinning the columns goes it was mentioned that they go from speed 1 to 7 while they are on the spinning wheel sets. The initial slow speed would allow the concrete to press against the mold without any risk of deconstruction of the mix and then as the speed increases the centrifugal forces will evenly compact the concrete against the mold. The steam curing provides heat and moisture to facilitate the proper curing of the concrete in a shorter time frame than if the concrete was allowed to cure normally. After all time is money and the sooner you have a finished product the sooner it can be delivered to the client and free up factory and yard space.
In 2:20 the operator is just placing the ring. The tension process (stretching) happens later, when the steel reinforcement is placed inside the mold, and continues until demolded. Sorry, I can hardly speak English
I have a degree in materials engineering, and have worked in concrete prestressed bridge beam construction. The comments below are correct. The steam aids in curing the concrete. The base plates are used to tension the steel rebar core. These both help speed the process and make for a much stronger end product. Steel is very strong in tension and concrete is very strong in compression. When you combine the two strengths of each you get an even stronger more flexible end result.
Интересно что будь этот ролик о производстве где нибудь в России, местные комментаторы сразу написали бы что это примитивно и все вручную, а иностранные смотрю восторгаются степенью автоматизации)
This is so optimized with some many specialized tools just for this job. It sometimes amazes me how some obscure items are still manufactured at enormous scale, so it is worth optimizing its production so much. The engineers who designed this plant, should be proud.
I thought the same thing; how hard it would be to make those columns without exactly the right tooling/fixtures. But when you have everything to do it right, it looks easy.
Amazing engineering application. Engineers have put in careful and thorough calculation to figure out the speed of centrifugal spinning and the right amount of cement to put in to make it work. Cheers!
Steam is used to speed up the curing process. Concrete does not dry, it chemicaly converts the cement and moisture into a hard substance. Heat speeds up all reactions, the use of steam provides moisture so that the concrete mix does not dry out. Without the steam curing they would have to wait much longer before de-molding and it would greatly decrease the factory's output.
@@ОлегЛукин-ф8д They are hollow and there are holes in the ends, and there does not appear to be a gasket where the two halves join. I very much doubt that they are sealed.
The Steps at 0:45, 2:23 and 5:15 belong together in a way. They attach 2 Plates a 2:23 one is hocked into the knobs at the end of the steel wire (created at 0:45) this one remains in the Pile and is used to attach it to other stuff during construction. the other plate bolts into the holes in the first one and has a central hole to wich a thick screw is attached in 5:15. What they are doing at 5:15 is an extremely important step. They are pre-tensioning the Steel wires (pulling very hard and fixing in pulled position) in 5:34 you see the bolt that keeps the Steel in tension and is attached to the plate from 2:23. This pre-tensioning makes the Piles much much stronger than ordinary cast in place concrete piles. This process is also almost impossible in ordinary construction and really only done in pre-cast concrete (except in bridges). In normal concrete you have to develop cracks for the steel to take any load. With this method the pile may stay crack free depending on load.
Used in concrete buildings also. Post tension. They pour with these cables all the way thru floors and then they tighten the ends squeezing the floor together from the ends. If piping has to run from floor to floor x rays are done so post tension cables aren't compromised, when drilling thru floors
@@pauldoyne743 Concrete works in one way that is compression. Wires are being used to make concrete work in tension. The problem is before wires generate enough force concrete cracks and lose some of its strength. By pre-tensioning wires works (generates bigger force) before deformation or bigger cracks happen when tension loads occur. ( earthquake )
Heavy industry...it's an another universe. I had the chance to work for one, the most interesting and one of the best work/life experiences i ever had. I could use a machine of 400000 euros and weld with a MIG/MAG welding machine of 20000 euro worth 😍. I stayed only 6 months. After 1 month, with all the coaching of the team and the manager, i was ready for production and was in the green in production time!!! We started at 4:00 and finished at 14:00, sometimes we got to start at 2:00, it was perfect, no traffic jam at those hours X'D. The job was awesome : safety equipment, tools, the products... But sadly, it's not well paid. I couldn't afford to stay there, one of the hardest choice in my career. What kills me the most, is that in Europe, every manual work sector is short handed. Well of course nobody is gonna work for a shitty pay! Really sad and stupid. Because those jobs are equal as being an engineer or a doctor, you gotta be rigorous, if not, somebody can be hurt or killed, if you take your job lightly or if you don't give a damn f***.After that, I worked in Switzerland as an IWS in an office, sitting all day long on a chair...i had the triple salary without the overtime pay. The job consist on coordinating welders, redact welding procedures, keep the welders certification in check with the task they do, etc, etc. I lasted 6 months, it was interesting, i had to work with awesome TIG welders, god welders to be precise. I asked my boss if i could work with them, to learn how they weld, to have a better view of how they work and to perfect their procedures. He said no X'D. How do you expect me to coordinate people and perfect their work procedures if i don't know how they work! X'D epic. That was the second hardest choice in my career X'DDD
There is no way you are spinning these on site. What you were using is a different kind of pile entirely with different properties and installation methods no?
I really enjoyed this video! Very educational and to the point. It was a lot better than many videos I've watched. Keep up the good work! I like the fact that you encourage people to add knowledge in the comments. 😊
My father was in the Korean War serving in the US Army in a Corps of Engineers construction battalion as a surveyor. The battalion specialized in Railroad construction, bridge repair, airfield construction. And demolition of same. The Americans were greatly impressed with the use of prestressed concrete by the Japanese throughout Korea. They were further impressed about the skills of the Korean labor force and Korean supervisors. I can only imagine how impressed he would have been with this.
Now you might be even more impressed when Biden begs for a good Russian missile right into the center of the Pentagon. Impressions will be enough for several generations.🤣🤣🤣
@@vorstellung3861 you are correct vorstellung. Ever since the Korean war, the cia has taken over the entire thinking and command of US foreign policy and focused on regime change worldwide, meddling in everything, including banking, and putting us where we are now.
But all of my friends have columns like that! ;) That was fun to see, and thank you and thank the workers of the company that allowed you to share in the hidden details of all that goes into our cities and buildings. While unseen, piles and structural support columns make modern buildings feasible, and their importance is often overlooked.
thank you and the factory for sharing with us.... im from the US and have operated many concrete boom pump trucks (possibly another video idea?) anyhow mad respect for these guys and this production not to mention the acceptionally clean (in my opinion) work environment.... very impressed thanks again and hello from Arkansas USA
This is so cool to see a smooth surface tube being formed just by a centrifugal force from spinning the mold... Remember, there was no cast inside the pillar, only on the outside. That means they have to use the same carefully measured amount of concrete mix each time, with controlled dispersion, to obtain the same wall thickness.... Lots of effort went into developing this technology.
You make really informative videos and I like your relaxed attitude to your commentary. You admit if you don't know something, instead of making something up like a lot of the channels which make similar videos. This is weird but I actually look forward to reading your commentary, it seems so friendly yet intelligent :)
Great to see some real manufacturing ..... many people today are ignorant of the dedication skilled men who make repetitious parts day and day out ..... these are the people who should be our CELEBRITIES ........
Центрифугированная опора. Хорошая, но очень хрупкая вещь. И дорогая. В Союзе повсеместно использовали так как давало экономию на бетоне при значительной высоте (центральная часть опоры или балки не несет нагрузки, а только добавляет вес, поэтому двутавр крайне эффективен, а рельс похож на двутавр). Но есть проблема - химия и токи утечки съедают опору напрочь. В Новомосковске, есть несколько опор, которые повернуты в сторону комбината. Там уже нет бетона. В Самаре сколько этих опор вандалы попротили. Сейчас переходят на оцинковку, но суть не меняется.
самое интересное что китайцы и корейцы железо ( арматуру ) закупают в США . может кроме сырья вова и смог чего-нибудь продавать , но в качество учитывая его патологическую жадность и тупость ему никто не поверит . Тут говорили про ржу , так некоторые стали , как те которые делали при Ленине рельсы - тоже не ржавеют , и арматура с определённым углеродом , только чтоб не превратилась в чугун , тоже будет долговечна .Самое главное видно , что на таком серьёзном производстве не экономят и не бомжуют на людях ... этого здесь ни один псевдоспециалист не увидел .
That's the beauty of civil engineering ❤️ We've done endless hours of hand written calculation in our engineering studies to reach this kind of perfection at industry level.
As I'm sure others have stated, the steam HELPS cure or harden the concrete it will take a whole to fully cure. My favorite part was watching how the cages are made. Very cool stuff thankyou for sharing
I may answer some questions... Concrete has a "curing" period in wich it's (initially) super prone to dehydration (up to 7 days) and then a late curing period (up to 28 days) in wich it's prone to rupture, you must take care of it for a whole month before it gives you all you expect of concrete... But in fabricated pieces like this you use some additives to shorten all the curing (2 hour to set, 7 days to hydrate, 28 days to strenght) you chemically make it all (sorta) done ASAP, that's where the steam treatment comes from, it heats the additive and concrete to have something we call "high early resistance", reducing the 28 days to one... Also it being full of moisture Will keep concrete from losing any... All of this just to make so the molds are avaliable earlier (those are expensive molds). The most amazing part of this process to me tho was seeing how it was made hollow, by spinning, that process in my head it just wasn't supposed to work lol, but it totally does, it blew my mind... Concrete sets as crystal "needles" and the spinning in theory should prejudice that process, resulting in weak concrete, but somehow they sorted that spinning range and speed just right to have a perfect piece at the end of the 2 hour setting period 🤯
I think high temperature in a steamy atmosphere helps the concrete to reach its standard exothermic reaction while curing without depriving it of too much moist on the outside and the inside hollow surface. It is probably the ideal environment for the fast curing concrete they chose.
@@lagresomadsl but you don't want it to do that too fast, especially in such thin sections as these. They are heating the casting up to speed the curing reaction and keep it uniform, so they also have to steam it up to slow the concrete loss of humidity and prevent the casting from cracking.
Awesome! Thanks you so much for the video, and to the workers + managers for letting you film! I can't believe that sucking-device actually lifted that pile out of the mold - that must be some insane suction power....
정말 좋은 영상이네요. 우리가 보이지 않는 공간에 우리의 일상을 지탱하게 도와주는 다양한 것들이 있다고 생각합니다. 이러한 파일도 어떻게 만드는지 몰랐는데, 이 영상을 통해서 생각보다 복잡한 과정과 기술들 그리고 노동자들의 노고가 존재함을 다시 한 번 느낍니다. 진심으로 좋은 영상 감사합니다. 계속해서 다른 영상 찾아볼게요. 그리고 ㅜㅜ 수도 없이 많은 공장에 영상 촬영 요청을 하시고 거절을 당하시는 것 같은데 그 노고에도 진심으로 감사합니다. 해드릴껀 없고... 구독과 좋아요 눌렀습니다.
I've worked in a lot of places similar to this in the US. It always seems like the line workers are much older than in the US. Maybe it's job retention. Every year I wonder how I'll still be doing this when I'm 50 or 60. Well now I'm 53 so I guess we find a way. I've moved on from some down right rough jobs that I would not be able to do anymore but I'm not getting any younger...and just more crippled each year. Beer helps.
I hear ya. Back in the 80s I installed those large satellite dishes for almost 10 years. No idea how many holes I dug using spud bars and post hole diggers, sometimes I'd do 3 or 4 a day. Trashed my rotator cuffs and have degenerative discs in neck and upper back from all the impact of spud bars on rocks. A dirt bike mishap and being rear ended by a drunk didn't help any. Was really good money but man, I am still paying for it decades later. Glad to be retired now.
Truly amazing engineering/production. Long time(s) ago I temped in a PVC pipe factory; later on in galvanized steel but this is incredible! & does look quite safe compared to many sketchy facilities doc'd on YT. Thanks for posting!!
Reminded of my previous workplace where we produce prestressed high tensile concrete piles. The piles must go through an oven called autoclave and finishes with a radioactive test to ensure they are completely dry on the inside and no bubbles or holes. Very good quality piles.
Radioactive test? There are several methods of non destructive testing, such as ultrasound, and radar. But, I have never heard of a 'radioactive' test. (Alpha particles are fairly common in soils but are not good penetrators. But neither Beta nor Gamma rays seem likely either. Are you sure radioactivity is used in the testing?
He's probably thinking of X-ray penetration testing. You're correct about alpha particles - they don't even penetrate the surface of our skin.@@gregparrott
※This video does NOT include any paid promotion※
※ 위 영상은 유료광고를 포함하지 않습니다 ※
📦 제품문의(Product Inquiries): www.tongyangphc.com/main.htm (동양파일)
🎬 촬영문의(Filming Inquiries): factorymonster2021@gmail.com
-We film for the company who are proud of showing how their products are made.
-팩토리몬은 제품에 자신있는 소상공인 분들과 중소기업을 대상으로 무료촬영을 진행합니다.
Copyrightⓒ 2021. Factory Monster. All Rights Reserved.
😊😊👍
Почему одни сваи зелёным красят, другие синим? Цветовая маркировка? Разная твердость, или бетон влагостойкий?
Wow
Eeeeeeeeeeeeeeee
@@dok.Sanger интересно почему они полые 🤔 может это трубы железо бетонные?? 🤔
wow i was surprised that a big factory like this one allowed you to film their processes to precast these piles. Thank you for sharing!
Thumbs up for shy worker being blurred out. In a time where privacy is gone I do appreciate you taking the time to blurring out a person who did not want to be on camera. And a shout-out to all the people working factory jobs. One of the hardest work environments there is no matter what part of the world you live in. If politicians were 1/1000th as hard working as you, the world would be flawless.
اله واحد خالق مريم وعيسى عليه السلام @Repent and believe in Jesus Christ
Bro, shy worker?? That guy is wanted for multiple wrong doings and was just released from jail. Hello. He told that camera guy to Piss Off. 😶
thumbs up for this very sensible comment
@SeniorMoostacho what are you talking about? You're making up absolute nonsense.
Politicians work like demons, but it's to get the support of people with money, not to make life better for their voters.
대한민국 산업발전의 역군들.. 항상 존경하고 감사합니다
Phc말뚝을 근 20여년을 만지며 살았는데 말로만 듣던 제조공정은 처음 봤습니다 영상 감사합니다!!!
별 말씀을요 ;) 시청해주셔서 감사합니다!
Я натурально залип за такой тех.процесс. Как же всё настроено и отлажено! Нравится наблюдать за слаженной работой.
Я тоже. Как эта свая стала такой геометрические ровной внутри, там же не было стержня?
@@maxpayne82 сам голову ломаю. Либо на этапе, когда её помещали для кручения, после засыпки бетона. Был момент, что рабочий закручивал какой-то стержень...короче не знаю))
@@maxpayne82 ЭТО НЕ СВАЯ СОВСЕМ!!! ЭТО ОПОРА ЛЭП!!!
@@maxpayne82 ВНУТРИ СОВЕРШЕННО РОВНАЯ ПУСТОТА ОТ ТОГО ЧТО ФОРМА ВРАЩАЕТСЯ, НА ВЫСОКОЙ СКОРОСТИ , И БЕТОН ЗА СЧЁТ ЦЕНТРОБЕЖНОЙ СИЛЫ РАСПРЕДЕЛЯЕТСЯ РАВНОМЕРНО ВНУТРИ ПО СТЕНКАМ ФОРМЫ
В Северном потоке покруче технологии) труба, потом каркас из арматуры и в бетон. Опоры в Крымского моста тоже непростые, их там около 600 штук
최초 작업 단계부터 마지막 작업까지 순서대로 하나하나 Process를 표현해 주셔서 이해가 쉽네요
Incredibly complex process to build high strength reinforced concrete piles. The video editor has done remarkable job by covering each stage of this precise process. 👌👌👍👍
Thank you for no music and leaving all machine sounds in. Slower editing (longer shots) would be great!
저 공장 영상은 몇번 봤는데 설명이나 자막이 없어 그런가보다하고 대충 넘어가는 부분들이 여기선 친절하게 설명해줘서 흥미롭게 봤습니다👍
Re: your questions during the video
The first object they were securing to the steel cage was the baseplate. This is the "top" of the piling, as the piling will be sunk into the ground. The steel building will be bolted and possibly also welded to these baseplates.
The steaming helps the concrete cure faster. It hardens better, faster this way.
Thanks for uploading this video; nobody will ever see those pilings when they are in use but it is nice to know what the roots of your high-rise look like.
That baseplate and later on at the 5:15 mark are also probably part of pre-tensioning the reinforcing bar.
To add to the steaming part, it's done after the concrete has had enough time in the centrifugal tumblers (my name, don't know the official name) to set up enough that the walls don't collapse under gravity. No "massaging" is taking place ;']
I want them under my next house
Wonder what kind of threadlock they use to hold a building down LMAO
👍👍👍
Less watewr better for the lasting concrete.Water too much dilutes chemical process and make weak concrete ans above that when it dry it shrinks and cracks which is not good.
15 million views...8 days. Actually restores faith in humanity that so many appreciate good workmanship, organized factories, good productivity.
Great video!!!!
yes great video
Slave labor. Work or else.
🥰🥰
*interesting video. the number of views is also amazing) good luck to you* 🔥🔥🔥
Even it is not a paid promotion, it feels like I have to buy a few of those column, just because how awesome it was made. 😂
same!
Very reasonable
Most impressive flagpole the neighbors will ever see! 😂
it would be fantastic to have two just on each side of the entrance... making it look like i have a huge estate.
What would a couple of these bad boys set me back? Thinking of building a suspension bridge.
The steam curing is probably needed for strength. Concrete always cracks as it cures - there's no way to completely stop ALL cracking. If it develops large cracks, the concrete will be weak, but if it only develops micro cracks that you can't even see, it will be MUCH stronger. One of the ways you can minimize cracking is by keeping the concrete wet while it cures. That's why when they pour concrete driveways, it's best to keep misting water on them for a day or two. It will increase the strength of the concrete tremendously.
Another way to minimize cracking is to keep it the same temperature all over the concrete. And since the center will get quite hot (concrete makes its own heat as it cures), they use heat to keep the outside from cooling off too quickly.
And what is hot AND wet? Steam.
Thanks for explaining
very helpful explanation
Concrete cures the more its moist. its a process called hydration and it happens over time. concrete gains its full compressive strength over months. The steam helps penetrate the micro grains of the concrete compared to letting diffusion to the work, which takes longer i guess.
My thoughts exactly as I do concrete work work myself
Not really, it's a chemical reaction with the limestone inside the concrete, where if you grind up limestone, bake it, then get it wet again, it hardens up greatly, and it will just keep getting harder the more and more it's exposed to water, with diminishing returns granted
현대사회의 시작이자, 건설의 기초, 어쩌면 기술력의 기본이 될 수도있는 기둥이 이렇게 만들어지는군요 좋은영상 감사합니다
멋진 댓글 감사합니다!
so efficient, they have everything set up to make it easy for the workers. They can be as productive as possible and not get hurt
job looks very dangerous. easy for a tension cable or support to fail and you're toast or seriously injured. glad i don't work in this environment. jobs like roofer, fisherman, logging, steel work, construction, farming, etc. are too dangerous to life or limb. not for me at all. lol. but glad someone is willing to take the risk so I can live to 90 enjoying shopping, travel, restaurants with friends and family and pursuing leisure, exercise, hobbies. there's a job for all ranges of abilities and temperaments.
А я думаю как же они так точно бетон накладывают?))) Так они же полые !!!)) Центрефуга это сила !!))
Я всеравно не понял как они рассчитывают на данную толщину бетон, он же заподлицо с крепёжных элементом без какой либо шлифовки и доработки
@@ВанекКобрин опалубку не заметил? а еще арматура предварительно нагружена.
@@ВанекКобрин для этого есть техрегламент, там все написано, какой обьем бетона, вид арматуры и тд
1. 자막 귀엽다
2. 용접이 너무 빠르게 회전하길래 대충 용접하는 대신 용접점 많은 양빨로 내구성 지키는갑다 싶었는데 한쪽 잡고 들어도 안뜯기고 콘크리트 저래부어도 안뜯기는거 보면 신기하네 용접 ㄹㅇ 잘된듯
3. 콘크리트 저렇게 입자 굵은 상태로 들이붓는거 첨봤는데 원심력만으로 저렇게 매끈하게 다져지는구나
Thank you for english subtitles.
You’welcome :) Thank u for watching my video!
The hysterical subtitles make the show!
The plate and the bolts into the endplate at about the 2:20 mark serve dual purpose. It helps hold the rebar steel pattern in place, and it looks like it pulls it into tension. The "P" in PHC stands for pre-tensioned, which is where you pull the steel before casting the concrete around it, and it essentially makes the concrete "tighter". This has to do with the relative strength differences concrete has when it is pulled vs. when it is pressed.
The oil is formally called a "form release agent", which really does the same thing oil in a cake pan does.
Steam is used to cure this concrete, I'm going to guess because it is hot and wet. Concrete needs a lot of water to cure (harden), and a high-strength concrete has a lot of cement, and therefore needs a lot of water. This is a chemical reaction, so if you write it out, there's no water in the end result. Keeping it hot and saturated speeds up the reaction by giving it plenty of reaction material and energy.
I'm shocked they're hollow in the middle, which was a surprise after they spun the cylinder. I normally don't work with PHC piles, and spinning concrete is usually not recommended because you can separate the components and end up with uneven distribution. It's quite a fast speed, so I'm guessing the aggregate mix has to be very uniform to avoid this problem.
Thank you for posting, this has been very interesting to me.
Kevin C Yes you can bet they have worked on every aspect of their concrete mix. You bring up a good point of the different materials in the concrete can't separate when it's spinning and have to stay properly mixed. Not easy to do I imagine.
Good comment
You know concrete. Well explained. Thanks.
Kevin C. Well commented! As far as spinning the columns goes it was mentioned that they go from speed 1 to 7 while they are on the spinning wheel sets. The initial slow speed would allow the concrete to press against the mold without any risk of deconstruction of the mix and then as the speed increases the centrifugal forces will evenly compact the concrete against the mold. The steam curing provides heat and moisture to facilitate the proper curing of the concrete in a shorter time frame than if the concrete was allowed to cure normally. After all time is money and the sooner you have a finished product the sooner it can be delivered to the client and free up factory and yard space.
In 2:20 the operator is just placing the ring. The tension process (stretching) happens later, when the steel reinforcement is placed inside the mold, and continues until demolded.
Sorry, I can hardly speak English
the comments aka subtitles actually ad joy to the whole experience of the shop tour, thank you!
I'm surprised at how smooth the inner surface is. Just from spinning!? Thanks for sharing and adding captions. 🙏
I have a degree in materials engineering, and have worked in concrete prestressed bridge beam construction. The comments below are correct. The steam aids in curing the concrete. The base plates are used to tension the steel rebar core. These both help speed the process and make for a much stronger end product. Steel is very strong in tension and concrete is very strong in compression. When you combine the two strengths of each you get an even stronger more flexible end result.
There is always someone who have some paid degree of something and want to shout it out....
@@dot7107 Looks like you have an online certificate in 'Wanna be Troll' :D
@@forgedude with a basic knowhow from concrete you can figure out what this "material engineer" wrote...
@@dot7107 yeah sure, but he probably lerned a bit more like the mixing ratios, how they change the forces und how to calculate the properties etc
so what the heck are these things used in?
What an amazing process. The factory is immaculate and each worker just doing what they need to be doing. Well done.
예전 공사현장에서 일할때 공장점검 간다고 많이 다녔던 공장이네요.. 이렇게 전 과정을 한번에 다시 볼수 있다니 예전 생각도 나고.. 좋은 영상 감사합니다..
일 하시던 곳 생각 많이 나셨겠어요! 시청해주셔서 감사합니다 :)
It is first time for me to see how huge concrete piles are made in factory. Thank you !
It was for me as well :) Thanks for watching!
Корейцы самый самый лучший народ желаю процветания, здоровым детишкам,успехов на работу.
Возвышать один народ над другими - это национализм. Нельзя так.
Russia has destroyed a children's hospital in Ukraine. Russia is an evil country.
Потрясающе однако. Респект ☀️☀️☀️. Инженерная мысль на высоте.
Интересно что будь этот ролик о производстве где нибудь в России, местные комментаторы сразу написали бы что это примитивно и все вручную, а иностранные смотрю восторгаются степенью автоматизации)
@@НиколайБелый-ъ2я ну так у нас все плохо и мы плохие а у них все хорошо все правильно и они хорошие
заметили, что русским сердечко не ставят? русофобия однако!
A rather good video, well I liked it. I also like the format, no talking. 🤩🏴
Your comment made me happy :) Thanks for watching!
감사합니다.
땅속에 박혀 보이진 않지만 우리의 안전을 책임져주는 작업자분들께 감사의마음 전하고 싶습니다.
Have stolen noi
The most amazing concrete engineering bots I've seen so far & those pipes are perfect!!! 😲 Wow! Thanks for filming this
와.. 시간가는줄모르고다봤어요..🥺 저렇게 만들어지구나..ㅠ 너무너무신기하고 작업하시는분들이 언제든 조심히 조금이라도 다치지않으셨으면 하는 마음으로 봤어요,,
Nicely done ; very interesting and informative !
This is so optimized with some many specialized tools just for this job. It sometimes amazes me how some obscure items are still manufactured at enormous scale, so it is worth optimizing its production so much. The engineers who designed this plant, should be proud.
I thought the same thing; how hard it would be to make those columns without exactly the right tooling/fixtures. But when you have everything to do it right, it looks easy.
@@scubasleeve3497 And I imagine all that tooling is one off custom made, must be really expensive to put a plant together like that.
Amazing engineering application. Engineers have put in careful and thorough calculation to figure out the speed of centrifugal spinning and the right amount of cement to put in to make it work. Cheers!
Steam is used to speed up the curing process. Concrete does not dry, it chemicaly converts the cement and moisture into a hard substance. Heat speeds up all reactions, the use of steam provides moisture so that the concrete mix does not dry out. Without the steam curing they would have to wait much longer before de-molding and it would greatly decrease the factory's output.
😊😊😊👍
Пар служит для равномерного прогрева но никак не превращает воду в твердое вещество. Форма герметичная.
Thank you so much for the details! :)
@@ОлегЛукин-ф8д They are hollow and there are holes in the ends, and there does not appear to be a gasket where the two halves join. I very much doubt that they are sealed.
Steam curing is a great method to speed chemical reaction. Sometimes use of a high-early mix is used. It cuts cure time from 28 days to 5 or 7.
Awesome video, should be shown in every university where pre/post stress and high strength concrete are explained🙌🏼
right
토목공학 전공자인데 이런거 첨보네요, 신기하고 어떤부분은 이해도 가고, 교육자료로 사용해도 퀄리티 높을 것 같네요. 재미있는 영상 감사합니다.
감사합니다 :)
The Steps at 0:45, 2:23 and 5:15 belong together in a way. They attach 2 Plates a 2:23 one is hocked into the knobs at the end of the steel wire (created at 0:45) this one remains in the Pile and is used to attach it to other stuff during construction. the other plate bolts into the holes in the first one and has a central hole to wich a thick screw is attached in 5:15. What they are doing at 5:15 is an extremely important step. They are pre-tensioning the Steel wires (pulling very hard and fixing in pulled position) in 5:34 you see the bolt that keeps the Steel in tension and is attached to the plate from 2:23. This pre-tensioning makes the Piles much much stronger than ordinary cast in place concrete piles. This process is also almost impossible in ordinary construction and really only done in pre-cast concrete (except in bridges). In normal concrete you have to develop cracks for the steel to take any load. With this method the pile may stay crack free depending on load.
Used in concrete buildings also. Post tension. They pour with these cables all the way thru floors and then they tighten the ends squeezing the floor together from the ends. If piping has to run from floor to floor x rays are done so post tension cables aren't compromised, when drilling thru floors
This is an incredible explanation thank you
Why would you pre-tension (effectively putting it in compression) a pile that is going to be in compression? I think you're wrong here.
Also you have to tension the whole thing to keep the steel from resting on the side of the mold due to gravity.
@@pauldoyne743 Concrete works in one way that is compression. Wires are being used to make concrete work in tension. The problem is before wires generate enough force concrete cracks and lose some of its strength. By pre-tensioning wires works (generates bigger force) before deformation or bigger cracks happen when tension loads occur. ( earthquake )
Well Done😊 Thanks for Video😍
Thanks for watching and comment!
Incredible machinery ! 👍
캬!!이런제조 기술들 정부에서 지원 많이 해줘야합니다.
파일공사만 3년째 회사다니는데
만드는 모습은 첨보네요 👍👍👍
Thanks!
Thanks for enjoying :)
Heavy industry...it's an another universe. I had the chance to work for one, the most interesting and one of the best work/life experiences i ever had. I could use a machine of 400000 euros and weld with a MIG/MAG welding machine of 20000 euro worth 😍. I stayed only 6 months. After 1 month, with all the coaching of the team and the manager, i was ready for production and was in the green in production time!!! We started at 4:00 and finished at 14:00, sometimes we got to start at 2:00, it was perfect, no traffic jam at those hours X'D.
The job was awesome : safety equipment, tools, the products... But sadly, it's not well paid. I couldn't afford to stay there, one of the hardest choice in my career. What kills me the most, is that in Europe, every manual work sector is short handed.
Well of course nobody is gonna work for a shitty pay! Really sad and stupid. Because those jobs are equal as being an engineer or a doctor, you gotta be rigorous, if not, somebody can be hurt or killed, if you take your job lightly or if you don't give a damn f***.After that, I worked in Switzerland as an IWS in an office, sitting all day long on a chair...i had the triple salary without the overtime pay. The job consist on coordinating welders, redact welding procedures, keep the welders certification in check with the task they do, etc, etc. I lasted 6 months, it was interesting, i had to work with awesome TIG welders, god welders to be precise. I asked my boss if i could work with them, to learn how they weld, to have a better view of how they work and to perfect their procedures. He said no X'D.
How do you expect me to coordinate people and perfect their work procedures if i don't know how they work! X'D epic. That was the second hardest choice in my career X'DDD
90년대말 다녔던 회사가 생각나네요...(동양파일 아님..)
작업공정 및 설비는 예전과 큰 차이가 없는듯 합니다. 오랜만에 공정을 보니 반갑네요...
좋은댓글 감사합니다 :)
저도 그때쯤 다녔죠
조립 캡 슈 가인장 마구리 했죠
오랜만에 보니 반갑네요
공정과 설비시설은 예전과 똑 같네요
누락된 부분이 있네요
1차 양생 후에 2차 양생기에 들어가는 것은 빠졌네요
Amazing, the machines are so modern and huge
I am a civil engineer. We used to pour these piles at site. I think it is very economical as well as cheaper to install.
There is no way you are spinning these on site. What you were using is a different kind of pile entirely with different properties and installation methods no?
이런 숙달된 기술을 가지고 자신의 위치에서 최선을 다하고 있는 종사자분들 너무 멋있다.
I really enjoyed this video! Very educational and to the point. It was a lot better than many videos I've watched. Keep up the good work! I like the fact that you encourage people to add knowledge in the comments. 😊
Before watching this. I never know that centrifugal forces could create such a smooth inner surface
Hello my friend,, excuse me 🤝🤝
Thought the exact same thing and saw your comment!
That's LOT of force at the RPM they were turning. A LOT.
@@turbodog99
agree..
만드는 과정을 소개하는 채널은 많은데, 건조하게 과정만 소개하는 타 영상과는 달리 자막이 재미있네요 :) 아무짝에도 쓸모없지만 저런 기계 하나 가지고 싶다는 자막 공감합니다. 구독 누르고 갑니다~
채널에 방문해주셔서 감사합니다!
와 엄청 흥미롭고 유익한 영상입니다!!! 굉장한 공학적 노하우가 응집된 생산공정 같아요. 구독 좋아요 박고 갑니다~~!!
시청해주셔서 감사합니다!!
My father was in the Korean War serving in the US Army in a Corps of Engineers construction battalion as a surveyor. The battalion specialized in Railroad construction, bridge repair, airfield construction. And demolition of same.
The Americans were greatly impressed with the use of prestressed concrete by the Japanese throughout Korea. They were further impressed about the skills of the Korean labor force and Korean supervisors.
I can only imagine how impressed he would have been with this.
the korean war would be the last successful US intervention after ww2 sadly
anyway i hope republicans win this upcoming election and trump comes back for the sake of americans
Now you might be even more impressed when Biden begs for a good Russian missile right into the center of the Pentagon. Impressions will be enough for several generations.🤣🤣🤣
@@vorstellung3861 you are correct vorstellung. Ever since the Korean war, the cia has taken over the entire thinking and command of US foreign policy and focused on regime change worldwide, meddling in everything, including banking, and putting us where we are now.
Thank you father devotion in Korean war.
But all of my friends have columns like that! ;) That was fun to see, and thank you and thank the workers of the company that allowed you to share in the hidden details of all that goes into our cities and buildings. While unseen, piles and structural support columns make modern buildings feasible, and their importance is often overlooked.
Thank you!
토목설계회사에서 엔지니어로 일하고 있습니다! 매일 CAD로만 봤던 PHC pile이 저렇게 만들어지는지 몰랐습니다. 흥미롭네요.
Oh man, I love "How It's Made" videos.. I also found the subtitles so entertaining and I have no idea why. Awesome vid! 👍
Without the 9 hr steam the concrete cures fully in 28 days, the steam makes the columns able to be demolded and stored for further curing
Thank you so much for the details !
And also adds moisture to the concrete to prevent cracking.
Steam curing has also been shown to improve strength if done with the right mix design by as much as 25%.
The tone used in subtitles are so wholesome that it makes me almost impossible not to praise the creator. Thanks man.
Thank you so much!!!
thank you and the factory for sharing with us.... im from the US and have operated many concrete boom pump trucks (possibly another video idea?) anyhow mad respect for these guys and this production not to mention the acceptionally clean (in my opinion) work environment.... very impressed thanks again and hello from Arkansas USA
Thank you for your effort capturing this much as best you can! interesting subject, no daft music, useful text, 10/10, would buy columns again! ;)
촬영 너무 잘하셨네요. 기술이나 품질이 너무 좋아서 일본인가 했는데 우리나라라니 뿌듯
제조 관련에 더불어 촬영도 칭찬 받으니 기분 좋네요 :) 댓글 감사합니다!
KOREANS ARE AN AMAZING PEOPLE..VERY HARD WORKERS
This is so cool to see a smooth surface tube being formed just by a centrifugal force from spinning the mold...
Remember, there was no cast inside the pillar, only on the outside. That means they have to use the same carefully measured amount of concrete mix each time, with controlled dispersion, to obtain the same wall thickness....
Lots of effort went into developing this technology.
@SUBJECT M01 exactly! ☝🏻
Haha I always enjoy the commentary on the video !
@Factory Monster, it was an interesting and informative video. Thanks
Thank you for saying that!
현장에서 파일은 흔하게 많이 보는데 어떻게 제작되는지는 몰랐네요 생각보다 는 복잡한 과정을 거치는 군요 , 재밌게 잘봤습니다.👍
Greetings from UK. I love your videos especially your subtitles. You have a great sense of humour 👍👍👍
Glad you like them!
현장에 계신 아버지, 가장님들 고생 많으십니다. 다치지 마시고 오늘하루도 화이팅 입니다
These are called Spun piles .The steaming process is to make the concrete harden fast ,so as to do the demoulding process at early stage .
Thanks for your comment!
@Repent and believe in Jesus ChristThere is no god
Satisfying video 👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍
thanks!
You make really informative videos and I like your relaxed attitude to your commentary. You admit if you don't know something, instead of making something up like a lot of the channels which make similar videos. This is weird but I actually look forward to reading your commentary, it seems so friendly yet intelligent :)
Never thought that concrete pile making is this difficult & includes of full heavy machines 💫👌
Mind blown 🤯
댓글에 영문이 더 많네요..좋은 자료 감사합니다!! 너무 촬영을 잘 하셨어요...건축전공자인데...이런 좋은자료를 보여주셔서 넘 감사합니다!!~
The Process of Making Very Strong High Strength Concrete Pile👍💝
Damn dog, thats a rocket scientist.
The plant designers have done great work. They're clearly creative and inspired Engineers.
Looks tedious for the blue collars though
At least it looks pretty safe.
@@paulmurgatroyd6372 I thought the same thing.
Horrible for the today white collar in a different proffesion
@@angatiawycliffe1258 what do you mean? Please rephrase your comment. Thanks
Great to see some real manufacturing ..... many people today are ignorant of the dedication skilled men who make repetitious parts day and day out ..... these are the people who should be our CELEBRITIES ........
Центрифугированная опора. Хорошая, но очень хрупкая вещь. И дорогая. В Союзе повсеместно использовали так как давало экономию на бетоне при значительной высоте (центральная часть опоры или балки не несет нагрузки, а только добавляет вес, поэтому двутавр крайне эффективен, а рельс похож на двутавр). Но есть проблема - химия и токи утечки съедают опору напрочь. В Новомосковске, есть несколько опор, которые повернуты в сторону комбината. Там уже нет бетона. В Самаре сколько этих опор вандалы попротили. Сейчас переходят на оцинковку, но суть не меняется.
Новомосковск что в тульской обл.?
@@uragluk5174 он самый
@@grendleniafly5428 Ой какой очаровательный дрочь на импорт. Нормальные опоры были, учитывая сколько они отработали.
самое интересное что китайцы и корейцы железо ( арматуру ) закупают в США . может кроме сырья вова и смог чего-нибудь продавать , но в качество учитывая его патологическую жадность и тупость ему никто не поверит . Тут говорили про ржу , так некоторые стали , как те которые делали при Ленине рельсы - тоже не ржавеют , и арматура с определённым углеродом , только чтоб не превратилась в чугун , тоже будет долговечна .Самое главное видно , что на таком серьёзном производстве не экономят и не бомжуют на людях ... этого здесь ни один псевдоспециалист не увидел .
Я что то не просек, они что, преднатяг арматуры не делают?
Круто😎 👍 Всегда интересно, заглянуть, за кулисы 😌😅
Though i,m an Engineer and design these precast piles but happy to see their construction at factory . Thanks for ur knowledgeable sharing ♥️
Thanks for watching :) I respect you design those machines
That's the beauty of civil engineering ❤️
We've done endless hours of hand written calculation in our engineering studies to reach this kind of perfection at industry level.
Thank you!
As I'm sure others have stated, the steam HELPS cure or harden the concrete it will take a whole to fully cure. My favorite part was watching how the cages are made. Very cool stuff thankyou for sharing
Impressive and exceedingly satisfying to watch. 👍🏼
⭐️⭐️⭐️⭐️⭐️
I may answer some questions...
Concrete has a "curing" period in wich it's (initially) super prone to dehydration (up to 7 days) and then a late curing period (up to 28 days) in wich it's prone to rupture, you must take care of it for a whole month before it gives you all you expect of concrete... But in fabricated pieces like this you use some additives to shorten all the curing (2 hour to set, 7 days to hydrate, 28 days to strenght) you chemically make it all (sorta) done ASAP, that's where the steam treatment comes from, it heats the additive and concrete to have something we call "high early resistance", reducing the 28 days to one... Also it being full of moisture Will keep concrete from losing any... All of this just to make so the molds are avaliable earlier (those are expensive molds).
The most amazing part of this process to me tho was seeing how it was made hollow, by spinning, that process in my head it just wasn't supposed to work lol, but it totally does, it blew my mind... Concrete sets as crystal "needles" and the spinning in theory should prejudice that process, resulting in weak concrete, but somehow they sorted that spinning range and speed just right to have a perfect piece at the end of the 2 hour setting period 🤯
انت شو عملك
@@عليالبصراوي-ص2ر2خ engenheiro civil
와... 이게 이렇게만들어지는 거였군요...
운행중에 파일완성품 쌓아두는 공장마당이 보여서 지나갈때마다 저건 어떻게 만드나 항상 궁금했었는데^^
귀하고 재밋는 영상 진짜 잘보고 갑니다.
감사합니다.
감사합니다~!
저도 잘봤어요~~👍👍👍
Я работал на этом заводе
Wow Amazing Video I Love It How They Made Those Big Things 😱😱😱😱😱😱😱 Keep The Good Work From Edinburg Texas
Love all the specialised tools and machinery just for the processes in this
I think high temperature in a steamy atmosphere helps the concrete to reach its standard exothermic reaction while curing without depriving it of too much moist on the outside and the inside hollow surface.
It is probably the ideal environment for the fast curing concrete they chose.
Concrete dehydrate.
@@lagresomadsl )😊😊👍
they are cooking there rice in there as well
A
@@lagresomadsl but you don't want it to do that too fast, especially in such thin sections as these. They are heating the casting up to speed the curing reaction and keep it uniform, so they also have to steam it up to slow the concrete loss of humidity and prevent the casting from cracking.
Very interesting 👍
Thank you 😉
you too!
Awesome! Thanks you so much for the video, and to the workers + managers for letting you film!
I can't believe that sucking-device actually lifted that pile out of the mold - that must be some insane suction power....
That’s exactly what I thought! the suction power!
Or I was thinking it was magnetic and so is held by the steel in the cage, but maybe not?
정말 좋은 영상이네요. 우리가 보이지 않는 공간에 우리의 일상을 지탱하게 도와주는 다양한 것들이 있다고 생각합니다. 이러한 파일도 어떻게 만드는지 몰랐는데, 이 영상을 통해서 생각보다 복잡한 과정과 기술들 그리고 노동자들의 노고가 존재함을 다시 한 번 느낍니다.
진심으로 좋은 영상 감사합니다. 계속해서 다른 영상 찾아볼게요.
그리고 ㅜㅜ 수도 없이 많은 공장에 영상 촬영 요청을 하시고 거절을 당하시는 것 같은데 그 노고에도 진심으로 감사합니다. 해드릴껀 없고... 구독과 좋아요 눌렀습니다.
ㅠㅠ
이런 영상 너무 좋아요~~ 덕분에 귀한 구경했습니다
Great job with the welding bits.
I've worked in a lot of places similar to this in the US. It always seems like the line workers are much older than in the US. Maybe it's job retention. Every year I wonder how I'll still be doing this when I'm 50 or 60. Well now I'm 53 so I guess we find a way. I've moved on from some down right rough jobs that I would not be able to do anymore but I'm not getting any younger...and just more crippled each year. Beer helps.
Thats the summary of blue collar jobs. If if youre paid above average, the fact that your body gets broken means youre not exactly winning.
I hear ya. Back in the 80s I installed those large satellite dishes for almost 10 years. No idea how many holes I dug using spud bars and post hole diggers, sometimes I'd do 3 or 4 a day. Trashed my rotator cuffs and have degenerative discs in neck and upper back from all the impact of spud bars on rocks. A dirt bike mishap and being rear ended by a drunk didn't help any. Was really good money but man, I am still paying for it decades later. Glad to be retired now.
@@dev-debug I hope you made hay while the sun shone.
Calcium pills and steroid shots for me.
@@Fanta.... Actually yeah grew up on family farm. Hot and itchy but enjoyed working with my dad. Good times that I mess.
I’m really enjoying your camerawork, shot choices and framing. superb!
Truly amazing engineering/production. Long time(s) ago I temped in a PVC pipe factory; later on in galvanized steel but this is incredible! & does look quite safe compared to many sketchy facilities doc'd on YT.
Thanks for posting!!
Where’s YT?
Reminded of my previous workplace where we produce prestressed high tensile concrete piles. The piles must go through an oven called autoclave and finishes with a radioactive test to ensure they are completely dry on the inside and no bubbles or holes. Very good quality piles.
Radioactive test? There are several methods of non destructive testing, such as ultrasound, and radar. But, I have never heard of a 'radioactive' test. (Alpha particles are fairly common in soils but are not good penetrators. But neither Beta nor Gamma rays seem likely either.
Are you sure radioactivity is used in the testing?
He's probably thinking of X-ray penetration testing. You're correct about alpha particles - they don't even penetrate the surface of our skin.@@gregparrott
Great video 📹 👍 👏
Thanks Thanks :)