See What Happens to a Hook When You Overload a Hoist
HTML-код
- Опубликовано: 20 сен 2015
- Click www.ozliftingproducts.com/over... to learn more about Overload Protection.
I shot a video today that shows what happen to a hook when you overload a hoist.
As you'll see it becomes a huge safety concern that can go easily unnoticed.
The best way to prevent this from happening is to use hoists with Overload Protection.
Overload protection protects the operator and takes the guesswork out of the weight of the load. If you guessed wrong the hoist will transition into overload.
Going into overload can cost you in 3 ways:
- Injuries
- Lost Production
- Maintenance Costs
Overload Protection helps reduce these costs and risk of injury.
Click www.ozliftingproducts.com/over... to learn more about Overload Protection. 
Наука
what you're discussing is the difference between plastic deformation (what you see by the red line) and elastic deformation (what happens when you load the hook and it comes back to the red line when you unload it). Elastic deformation shortly leads to rupture (well kinda shortly) but if you unload before rupture, the steel returns back down the load/deformation path to zero load. The next time you load the steel, it travels back up the same curve, which is offset a bit to the deformation direction, meaning you get to elastic deformation more quickly. If you stay within the elastic limit of the steel, theoretically, you can load/unload all you want. If you travel into the plastic deformation zone, your cycles of load and unload remain the same, but the magnitude of yield reduces and the load difference between yielding and rupture reduces. However, if you only to the plastic loading once, the hook should be ok for continued use, depending on how far you travel into the plastic zone. Steel attachments are usually rated at 20% to 25% of their rupture strength, you hook was rated at 10000 lbs meaning it's rupture strength should be 40000 to 50000 lbs, you made it to 30000 lbs, meaning you were coming up against the rupture strength of the hook, meaning your cycles in this zone next time are significantly reduced. (this, by the way, is strain hardening of the steel).
Knowing what you know, throw the hook away and get another one. the $150 for the hook is far cheaper than the litigation involved in dropping an important pick or hurting someone. BTW, dont throw the hook away. Cut it in half.
Excellent!
Hooke’s law on a hook😀
Yes, ' cause guys like me, would use it for lighter purposes. Like making a bumper tow rope...., when moving.....CUT IT IN HALF, ! GOOD ONE @
(Forgers' code : sleep, eat, heat, beat re peat.........for heattreat...)
The plastic defamation is not noticable by eye. This is beyond that
Can you recommend resources to learn more about this? I’m new to the industry and eager to learn more about promoting safe practice.
I took a millwright 16 and osha 30 course, they should show a video like this to explain the dangers of overloading hooks also
You mean osha should show a big fat nothing.
@@johnmarksmith1120 yeah sure what ever you say, chief
What's sad is I can't tell you how many times I've seen damaged hooks and the guys will still use it.
Thank you. And not just in overhead.
I did towing and recovery for 20 yrs. I didn't get why my keeper didnt work for years . Bow I saw this. And it explains it all . I way overworked my gear.
I wanted to see it break but it was still interesting AF.
I will mark my hook from now on. Great information 👍👍
‘Never overload your hoist!’ I’ve always said that!
Expected to see some shit get broken and casualties. Got this, thanks a lot.
So paint the hook at the latch as a precautionary warning.
A lot of hooks have 2 small holes at the side, between the opening. The distance between this holes is defined, and can be controlled. If this distance is wider than the defined one, it's bend.
Paint alone can be done additionally, but it won't last long on a hook which is often used.
WE WANTED TO SEE IT SNAP!!
Thanks very educational to me cause I am a crane operator which is good to know the hook block will stress out. 👍👍
A hook may be rated for 5 tons, but that doesn't mean it will break at 10, 15, or even 20 tons. It depends on the fatigue life of the hook at its rated load, how many load-unload cycles it has seen in service, the factor of safety against fatigue failure at the rated load, etc. It might be designed to withstand 5 tons with a factor of safety of 3 over 10000 cycles. Statically, it may be able to hold 13 tons before yielding, and it might break at 18 tons. It all depends on the grade of steel and heat treatment.
good information.!
You couldn’t show the overload process?
Why don't you make a video?
I know it was so annoying how the man explained something instead of DEMONSTRATING to us something BREAKING YEAHHHH
i spent 40 years repairing hoist of all kinds. its good to see this info being shared.
Agreed ✅ It Would be Nice if There were Location Marks for that Reason
Good to know the specs, and the mark is a great idea-as long as someone checks it.
I thought I was going to see it stretching and failing, nothing to see here
Honestly, I don't see a problem using that hook for a load its rated for, even after the deformation. Yes, it has been deformed, but not in a manner which I feel would cause a dramatic fail. It has been stressed into the plastic deformation range. I see no cracks or other indication of an impending dramatic fail. IT that slight deformation is a significant compromise of the hook, I'd expect the manufacturer to put marks on the hook, to make it obvious a deformation has occured, i.e. a series of parallel lines so deformation is blatantly obvious to anyone looking.
@@ravenbarsrepairs5594 Thats why industrial tool rooms tape hooks to mark this type of failure. Needs to be common practice. Once the original form of a lifting device is altered whether by lifting force or human force, it cant be trusted. Nor should anyone tell someone else it would be fine. If you know its been stretched, any outcomes afterward are on you. Thats why I alway told new hands, you see it you own it
@@hammerdick82 a safe hook or unsafe one makes little different once your not under the load
@@johnobrien2207 Very flawed logic. I hope you are never in charge of a project or job with that way of thinking
@@hammerdick82 ..do you have a machine for testing hope and vision..don t put yourself in a position that depends on the safety of a rated bit of equipment...things can go wrong...so I would not trust my life anymore on the new hook just out the box..that means stay the f# away from a suspended load or if it was used for towing example recovers...stay well clear..
Yeah that was a great VISUAL example of a hook failing! Tanks!
Good vid, frightening as well. I see devices like this all the time, and wonder in the back of mind just what their true state is. I keep my equipment locked up and know it's history.
I have just learnt something that I previously had no idea could happen. I truly thought these hooks were good forever. Would that be true if never used to the full rated limit, or will the hook simply develop long term stressing even under the max limit??
One question that does come to mind, why don't the hook manufacturers create a small grove where the latch meets and paint it a bright or contrasting colour??? Do they even do that in 2021??
Second question. Is there actually a design factor in the hook that allows for a percentage of stretch as part of the normal operation??? Does the MFD conduct a pre-stress to set the final end use???
Thank you RUclips recommendation...
The annual inspection performed on the hoist is supposed to identify a stretched hook by measuring the hook opening and comparing to mfg spec. Good quality hooks have marks cast into the hook that you can measure spread.
Some of the companies that I worked for just bought all new lifting gear;
Plate clamps; d shackles; wire cable rope; chains and hooks,
every time the inspection date came around.
Other companies said "go easy on that gear, it's old!"
@@benjigray8690there are standards for all those things depending on how much of the rated load is used and how often its used. A wire rope can look 100% fine and still need to be replaced every 3 months. Because the outside you see is not what takes the stress of the load, its the inner core which you cant see.
Thank you for replying.
you're quite right.about the "standards" that apply to all lifting gear
A while back, I applied for a job at a steel fabricating workshop.
The owner took me for a tour of the place, and the first thing he showed me was all of the different coloured lifting slings.
And he pointed out the favct that they all had recent inspection dates on them
then he showed me all the various machines, asking me if I was familiar with them.
I still live by the rule;
never stand under a suspended load.
@@benjigray8690 I actually work for one of those inspection companies. Its crazy the amount of standards there are. Its all about safety though, things fail all the time so companies are required to have the inspections done every month to a year depending on the use for liability reasons. If they are used for more than 65% of the rated load OR more than 25% of the time, they require monthly inspections. Then theres a plethora of other stipulations that could also require the monthly inspections like temperature and environment.
When I saw the hook I thought that it didn’t look right , as if the load bearing part of the hook was wrong
Safety video. Thanks. A lot of people are stupid when it comes to lifting and weight bearing capacities. Darwin.
oh man
How do you perform a load testing
Stretch point is well below failure point
That is the safety of a forging over a casting that is quite brittle and would fail catastrophically snap before it reached 30K.
@@epistte
Who has cast hooks in service ?????
They should add sensors in the hooks that detect how much weight is on the hook. If its over the amount rated for that specific hook, the sensor would send a message to the lift or whatever machine the hook is for, and not allow it to be lifted until the stuff you are trying to lift is within the limit of the hook
Some do - not everything needs that; it's expensive and this skillset has been around for a long time.
When you pick a set of chains op on a crane make sure both sides of the chains are of equal length.
If one side is longer they have been stretched and may explode.
...for precise accuracy, COUNT THE LINKS.....that, determines the total '' length '' of said chain.....
on the railroad it always cable or brake failure
This tip, by a few suppliers, come painted by default. It should be a requirement of standard.
I was waiting for the mouse to pop out...
Duly noted. In have no idea why they recommend me those videos.
The Hook has exceeded Hookes Law ( no pun intended) the force applied was way out of proportion to the elastic characteristics of the hook design ,hence did not return to its original position when the load was released.
As a Trucker I've only dabbled with hooks and Chains. Most my flatbed freight is with straps. I know when a strap is bad. But when inspecting chain
What do you look for? And how often do you look?
How are you supposed to tell if a hook has been overloaded without putting a mark there before loading it?
Quality hook manufacturers install two reference points across the mouth of the hook of a nominal size metic or imperial doesnt matter .
That measurent is supplied with the hook for future audit reference , then there is no concern .
Factories I have worked in we are trained in basic rigging with straps, wire rope and chains and load weights. The overhead crane inspection classes is where this information is learned and passed on to others.
In progress
Why don't the hooks have a permanent cast marking for the latch position which can then show when the hook has been stretched?
The explosive failure of the hook overload blew my mind 🤕.
They are made to bend, not to rupture instantly, it's a safety feature.
FLOUROSCOPE, WAS WHAT ARMCO DID WITH THE ALTERNATE LIGHT SOURCE. YOU COULD READILY SEE THE STRESS STRIATION FISSIORS OR CRACKS. I FORGET THE NAME OF THE POWDER, MAGNET, LOOKED LIKE A BLACK LIGHT. THAT WAS IN 1978.
Especially when your lifting control rods and other goodies out of an operational nuclear reactor 🤷🏻♂️😱🤷🏻♂️
You should have load tested both the top and the bottom hook of the chain fall you'll see of load testing both the bottom hook will go first before the top hook
oh!
you are talking about the load hook right not the top hoist hook right?
One hook is the same as the other. If one was overloaded, then the other will have been. The correct way to check it is to measure the gap in the opening of the hook and check it to spec. If it is greater than the maximum allowable opening, then it was taken past its yield point. It's according to how much it was overloaded, to whether it may have stretched or not, as all hooks will hold more than their rated load, as they have a safety factor to them. That's why the one in the video took 3 times the rated maximum load to stretch it.
There has to be a simple way to identify overloaded equipment.
Paint the entirety of the hook except the area below where he put that red mark
well thats why we have a max load on any hooks in service
Question: so why don't the manufacturers put a red mark on all hooks? It would make previous accidental overloading to the point of ductile stretch visually obvious during inspection. Sure it wouldn't catch all overloading but at least the egregious abuse would be visually obvious.
They are legally required to be inspected by professionals who dont need a red line to know if its deformed beyond manufacturer or legal standards.
-professional
i thought it was going to snap , bit disaponted
I wanted to see how it fails practically but only theoretically explained. Till the last second of this video I was expecting to see the hooks breaking ....but nothing
OK, it reached its yiield point at FOS 3, so? If properly designed it should snap at 45-50 kips, depending on material properties and breaking strength. If loaded more than 10,000 times probably even sooner.
I wonder how much force it would take to bring that hook to the actual point of failure. Probably orders of magnitude more than it took to cause that small amount of deformation.
@G Rossi ok, that makes sense.
Was waiting for the hook to crack and break at the right hand side....... such a let down!!
There should be a notch indicator on the hook where the tip of the latch should rest. If the tip of the latch is passed the notch indicator DON'T USE IT. 🤕👍
Keep pulling until something let's go
Took a look, I got hooked. Thought the hook would get cooked.
'See what happened'
You can fix that shyt with a red marker...
bit its still good for 5 tons
6
Well that was incredibly boring but it’s good safety information
Just the other day I was looking at all my hooks.....................
Because of that bend, every load will rest closer to the tip of the hook by *that much*. If you suppose there is no mechanical stress (and there is at least some), then the *thinner* part of that hook ought to be more inclined to bend to pressure than the hook's original rating. We're blind to what the hook can handle now. I fantasize I'd take a big risk: paint it florescent, put it in its own pile and label it good for half it's old capacity. I can't be sure of that but I see that as safer than treating the hook like the others. But don't take my bad advice.
This hook is garbage now. Cut it and throw it away. Carrying heavy loads is not a joke. It can and will kill someone.
30,000 pounds, baby, wow. Now I wanna see that sucker let go, Mythbusters style.
And
😆🤣🤣🤣 you wouldn’t believe how many times we overloaded machines (diesel engines)before @ no one ever got injured 👍👍🤛🤛🤛
Engineers design things for people like us. It's called a safety factor.
If that 5 ton hook can lift 30,000 pounds, it's NOT compromised.😂😂
Obviously you are a materials engineer and know everything.
WTF. Seeing what happens is actually seeing what happens
And you saw exactly that: What happens. Are you alright?? 🤣
Cool, I’m going to look out for the red mark on hooks. It’s interesting that this person is an expert on the matter yet talks in imperial????
Um...you do realize that using one form of measurement over another doesn’t make you smarter, right? Like, sure, metric is easy to convert and based on a universal constant, but implying that people are smarter or more professional if they use metric is like saying someone doesn’t come off as foreign unless they speak French. That completely ignores the other equally foreign languages. You’re ignoring the fact that, while only used in America and not easily convertible, imperial is still a completely normal system of measurement. What this guy has is experience. THATS why he’s an expert on the matter. Using metric doesn’t signify intelligence OR experience and implying that anybody that doesn’t use it while having either of those is weird only makes you a metric elitist. Perhaps you don’t realize that’s what you are, and it may not be a sin nor a crime. However, being secretly and weirdly snobby about a unit of measurement is an incredibly unattractive trait to have.
Sounds to me like they just load tested the hook to 30,000 lbs so by my line of thought it still oughta handle 5,000 all day long.
Yea, but the material is compromised. Could fail at any point now
I would think stress deformation may not be linear. Once you go over the limit, there's no warranty over how it will behave.
If it’s held 30 then it will hold 5 all day long. Admittedly it doesn’t necessarily give you a warm fuzzy and I wouldn’t stand under it but would still feel pretty secure at 5.
without video it never happened
The video should be titled 'See what happened to a hook AFTER it is overloaded'.
Yes. Great Safety Training. I Take Them With My Company. Our Safety Director Shows Worse Case. Then Discuss It. No One Likes Sitting In Office All Day. But Back On Road I Remember Him. Been In Contracting Many Years. Pay Attention To Small Stuff Like This. I've Seen Guys With Missing Limbs. Deformed Jaw. Ect.... Be Careful Everone. Rushing Job Ain't Worth Getting. Well You Know.
What the big deal, be cheaper to move the red line than buy a new hook wouldn’t it?
Lmao it’s cheaper until the hook fails and the business is paying out the ass in a negligence lawsuit. A red paint pen won’t stop it
All lifting equipment should checked once a year with all the reading
Actually all loose Lifting equipment should be inspected every 6 months. But it should be checked every time you use it
Wanna see stuff explode son
I didn't see anything very miss leading
Sure don't buy that big ass hook at HD, wow.
Naff all.
It would have been better if you showed it before, with lift, then after the lift.
There's a 1:14 I won't get back. Nothing to see here folks.
I was expecting to see it explode and kill thousands of people instead I see a dab of red paint on a black hook 😭😭
@PDF 🤣🤣🤣
Don't see what happens to a hook when you overload a hoist
This shows nothing,
What where you hoisting your wallet ?
Anti-climatic however informative. Sounds like a permanent marking showing relationship of clasp to hook should exist.
Not a single hook was hurt or even destroyed during the making of this clickbait video.
It's All About the Benjamins
Pffft... lame, where's the overloading and snapping part :-(
Stop moving damn camera
10000lbs equals 4.46 tons.
Bullshit I want to see video proof
CLICKBAIT
Saw nothing......thumb's down for clickbait.
god this is just talk!!! nothing shown here!!!
What CLICK BAIT!
where is the breakage, flying shards of razor sharp metal? I want a refund.
CLICKBAIT. Nothing happens.
Click bait.. just to get more views.. tsk.. tsk.. tsk..
Didn’t see it break. Dislike