How Good is Your Intuition??

I give that a GA- it's 250 lbs of upward moment per bolt, plus leverage that may be created by flex of the hub. As the weakest point is likely to be the bolt holes i'm going to take a step farther & say it will be at best minimally more.

I know this is some sort of trick, but I'll say 250 lbs minus the weight of the hub....

Since it is a trick it is 250 lbs PLUS the weight of the hub and plus the pretension from torquing.

^{Oh where is all my none -exisiting mechanical skills.}

250 lb total per bolt, but not spread evenly over the cross-section of each. (Plus any preload from torquing.)

How much torque was used to drive the bolts? If significant, it would change my answer to ; "much more than 250lbs".

I edited before looking at your reply, but after you posted. Future shock is upon us!

The funny part is that I tried to edit my first offering but had less than a minute available so I posted again.

The base weight has nothing to do with it. I just needed to show the hub is bolted to something. Assume the base is anything you want (concrete floor, large steel plate, etc)

Assume bolt torque is minimal only enough to ensure contact between all surfaces.

Now you are talking.

Second guess is 1000 lbs.

^{Yes it is just a guess - my own intuition!}

"The base weight has nothing to do with it", fine.

But the 'hub's weight' matters. Just for argument, if the hub weigh 1000 lbs, there would be no load on the bolts. And if the hub weighs more than 1000 lbs, say 1100 lbs, no bolts would be required!

"...if the hub weighs 1000 lb...". Uhm...it's 6.25" od x .54" thk. How can it weigh a 1000 lbs?. It's not a trick question.

I retract my reply to you. I read you comment again and understand what you mean. Sorry it's 2:30am and I can't read straight anymore. Yes the hub weight would matter but that's not the answer I was looking for. When I said the base weight has nothing to do with it I meant the hub. My bad. The weight of the components have nothing to do with the answer. The parts weigh very little compared to the applied load so don't consider the weights.

It depends upon how hard each bolt is flogged-up.

In a perfect (okay, imaginary) world, with evenly and just tight bolts and exactly vertical 1000 lb load, I'd give em 250 even. If it's bolted to the floor of a ship, well,you know what happens... Nice prize!

Zero pounds! The bolts have no heads!

If the four bolts are torqued against the hub, there will be a resultant tension. To this should be added 250 pounds due to the 1000 pounds of upward force on the central spigot divided by the number of bolts.

I overlooked the weight of the hub and spigot. Assuming zero tension on the bolts, the resulting tension per bolt would be (1000 minus the weight of spigot and hub) divided by 4. Something less than 250 pounds.

guess (no material info) 375lib>425lib it should bend and build support what almost double force

Fry #9 came the closest, but it is still a way underdefinded mechanical problem.

First of all, the slop (sideways freedom of movement) of the pull is undefined.

Second, the flexibility of the cross shaped is undefined.

Third, the yielding of the screws are undefined.

So, I attempt only one case: precise guides, flexing arms.:

As pull commences, one bolt after the other picks up the load, as the arms flex.

Arm #1 most loaded, above average

Arm #2 loaded above average

Arm #3 loaded below average

Arm #4 least loaded, below average.

That is the best possible statement possible, given the circumstances.

"the most important piece of info...the capital of Iceland is Reykjavik!"

Everyone missed the above most important piece of information by OP. Each bolt will experience 250 lb load, only if

1) there is no pretension due to torquing and

2) there is no differential thermal contraction between bolt and hub due to change in ambient temperature (on negative) of Iceland.

If I assume torquing is done at room temperature but later the object is subjected to negative ambient temperature of Iceland, which will result net positive contraction in bolt length; then the tension force on each bolt will be enormously higher than 250 lb.

Not necessarily. If Hub and bolts are both steel - any Steel analysis- Temp 20C makes no difference.

Not necessarily.

Why not? Where from this temp 20C came? It is not given by OP. If I assume room temp as 25C and ambient as -35C (which is quite possible at Iceland), then differential temp would be 60C. Also it is not given by OP that hub and bolt are both steel. They can be of made of different materials and different expansivities.

Interestingly, here hub has four stepped holes; each 0.88" dia 0.25" deep to accommodate 0.75" dia bolt head and 0.60" dia 0.29" deep to accomodate shank portion of the bolt. When bolt is screwed to base plate and torqued, this 0.14" step in the hub [(0.88-0.60)/2] is compressed from all round towards the base plate by bolt head. When 1000 lb pulling force is applied at centre, this step in the hub is pressing the bolt head upwards at the inner parimeter of the bolt circle. But at the outer parimeter of the bolt circle, step in the hub is still getting pressed towards base plate. Due to these forces in different directions, bolt shank will experience bending force towards outer periphery.

Still I stick to my answer at #19.

Iceland was irrelevant info just like all the dimensions. I tried to be funny and sarcastic. All material is steel. Material weight is insignificant. Bolt torque negligible. Enough only to make contact with hub and hold it against base. No pretension in bolts.

I am afraid that the nominal tension will be:333+1/3 lbs (ofcourse on 3 bolts!!)

If taken your restrictions - especially

-This based on the ideal plane configuration by 3 points - by definition !!

Nothing... Reason the shaft and the hub are incapable of taking the load and break at the force of 200 lbs pull You need more sophistication the shaft needs to be able to spread the load out. at the moment the force point is the joint between shaft and cross and that is just weak..

So far two of you have the correct answer. Okay maybe 3 of you. Out of the 2 or 3 their is one that is the best. Will elaborate tomorrow. It's 2:30am and I need to sleep. Cheers.

Impossible to say precisely with the info given.

It depends entirely on how tightly each bolt is torqued (the 1000lb load doesn't have that much to do with it).

If you torque one bolt to take the entire load, it will bear 1000lb plus pretension, but the load on the other three bolts will be negligible. If you then torque up the other three to the same as the first, each bolt will be bearing over 1000lb.

(I think?)

See post #8. No torque in bolts. Just enough to contact. Try again.

Can only say that the sum of the tensions on the bolts would be 1000 lb or more depending on how much preload is applied to each bolt.

if there any amount of clearance between hub and spigot , then spigot will move up alone and all bolts will be zero tension force.

it's just a new idea.

It is implied that the spigot is "part of" i.e. fixed to the hub, and the pull is 1000 lb.

Therefore, the 4 bolts suffer a tension of 1000lb pull minus the weight of the hub.
(ignoring tightening) the 4 bolts have a tension of 250lb - 1/4 hub weight each.)

(whatever that is, not looking up steel weights) Any complication?

If the spigot is not part of, nor attached to, the hub then the 1000lb pull will be
meaningless to the bolts, as will be the weight of the hub, being "under" the bolts.
(ignoring all tightening tensions etc.)

jt.

I bought a brand new digital computer controlled intelligent washing machine,
loaded it all up, and pressed start. It said, "where`s the other sock?"

My doctor has given me some anti-gloating cream.
Now all I want to do is rub it in......

There is two forces in play for each bolt.

1/ Is an almost vertical force.

2/ Is a small but relevant shearing force not at 90 Deg but somewhere in this plane.

The resultant of these two vectors will add up to 250 Lb neglecting any correcting factors such as the weight of the hub.

It cant be more than 1000 Lbs total.

I should correct my previous post in that the sum of the 2 vectors gives a resultant vector which will be larger than 250 Lbs.

I was stuck in the 1000Lb mode

It's like the 4 legged table problem - indeterminate.

Look at the problem this way:

The Sum Total of the applied load is exactly 1000#, and no more than that, since the bolts aren't pretensioned nor torqued.

Therefore, the total applied tensile load = 1000#/4 bolts = 250# per bolt.

If there is any "prying action" it will be minimal because the "hub" material is fairly thick and stiff.

A: So the resulting total tensile load per bolt will equal 250# per bolt less the prying action load per bolt. To check the tensile stress on the bolts all one has to do is divide that unknown load by the tensile area of the bolt (which is less than the Gross cross-sectional area of the bolt because of the threads.

Anyhoots, using a 250# tensile load will suffice and be minimally conservative....

The shown picture is analogous to a 'second order lever'.

Presuming so, we may rewrite this as:

Effort arm: 6.25"/2. Effort: 1000/4 = 250 lbs.

Load arm: 6.25"/2 -3.5"/2 = 2.75"/2.

Hence Load (on each bolt) = (6.25/2.75) X 250 = 568.18 lbs.

Yesyen, you've gotten four GAs but a simple free body diagram and leverage calculations like you've shown don't apply. That's why it's called a statically indeterminate system. Free body diagrams do not consider material, stiffness, geometry, etc. For your calculations and your diagram to be true, the horizontal line representing the "load arm" would have to freely pivot around a point where that horizontal line meets the line of the arrow below your "1000/4" text. The actual hubs arm is rigid, is one piece with the hub body, and does not freely pivot relative to the load applied. The leverage is caused by material deformation and NOT PIVOTING ACTION!

FEA proves it. Load is only 282 lb not 568.18. I took away one of your GAs. Sorry.

If there was a way to remove all your GAs...I would!

"Einstein thought that Newtonian mechanics was no longer enough to reconcile the laws of classical mechanics with the laws of the electromagnetic field. This led to the development of his special theory of relativity".

I totally agree with you there. Many of the answers were very good and clearly these people have a good feel for the problem, but this guy and some others are completely missing the point ( although it would sometimes be nice to live in such a simplistic world !!! ).

Being self employed I don't have access to FEA as yet, so I tend to look at the two extremes ( ie- Yesyens at one end and that of an ideal rigid body at the other, then try to make an informed judgement about where the answer lies between these two extremes).

Sometimes these problems can torment you for days ( I have a friend who refers to it as analysis paralysis ).

Anyway TerraMan this was one of the most thought provoking and enlightening posts I have seen for a while, keep them coming.

#1 seemed to have the idea--leverage. Each arm will have 250# at its inside end, but there is prying against the pads at the outer end. Assuming the bolt is halfway between, the bolt load will be 500#. If a different spacing than half, use a ratio. I don't think "slop" and flexibility will have anything to do with it unless you pull so hard that the geometry is changed--like the arms flex so much that they hit the floor instead of the pads.

I don't think "slop" and flexibility will have anything to do with it

Flexibility has everything to do with it. At one extreme is the Yesyen answer, which is impossible: the steel central portion cannot act as four independent hinged levers.

At the other impossible extreme is a perfectly rigid material, with which there can be no leverage or prying effect at all.

Somewhere in between is reality.

In hindsight, I believe YesYen nailed it by demonstration....therefore I retract my previous posting. I just didn't take the time to really look at the problem earlier!!!!

In his/her post, the Statics work....Sum of the Forces and the Sum of the Moments = ZERO each. Prying action as passingtongreen stated above is present!

He/she gets a GA from me.

You, sir, are tricky. Since Intuition is being evaluated, the numbers don't really matter, and the capital of Iceland is an important clue, the answer is obviously that there is no stress being applied to the bolts. The hub has been heated, the shaft chilled, and is simply being lifted free from the assembly.

As per my above post, this is a statically indeterminate problem, all that can be said is that the sum total of the tension in the bolts would be 1000 lbs or more.

Otherwise it is a problem in FEA, which is no longer intuitive.

Case1 and Case2 are not the same:

I take your point but surely we are looking at a "rigid" hub here not a simple system of levers.

True the answer will lie somewhere between your system and a hub with infinite stiffness. However the original post stated that dimensions were of no consequence therefore you cannot postulate about the rigidity.

Or am I missing the point!!!

It is intuitively obvious that the hub must flex when loaded. But it is also intuitively obvious that it cannot flex like bubble gum. So the intuitive answer is that the hub must act in a way that is between a group of hinges and a perfectly rigid body.

Absolutely agreed & GA- I've never touched an FEA program & am not a strucural engineer, but that was my thought.

Thank you sir for your kind words, I'm so glad that you agree with me, and hope that your rant has set you up for a good day. It must take great skill ( or is that intuition )to say so little in so many words.

Does the op (TerraMan) want us to say each bolt suffers the same 1000lb pull? i.e. a trick question? This is difficult to imagine
because if the 4 bolts were replaced with e.g.spring balances, each balance would show 250lb respectively. (shared load)

I look forward to the answer.

jt.

According to well-informed sources, the Japanese banking crisis shows no signs of improving. If anything, it's getting worse.

Following last week's news that Origami Bank had folded, we hear that Sumo Bank has gone belly up and Bonsai Bank plans
to cut back some of its branches. Karaoke Bank is up for sale and is going for a song.

Meanwhile, shares in Kamikaze Bank have nose-dived and 500 back office staff at Karate Bank got the chop.
Analysts report that there is something fishy going on at the Sushi Bank and staff there fear they may get a raw deal...

jt, you kill me! LOL

250 lbs net pull @ IT IS! Intuition,Colored Stress Analysis ,Iceland -- You keep these to yourself OP.And learn Vectors Once again . Good for you.

I think two key points about this problem are : 1- The "lip" on the base, which allows the hub to pivot. 2- If we take the picture offered to scale, the bolts are not positioned at the ends of the hub. So this appears to be a second class lever, where the resistance at the bolts to be deduced is somewhere in between the effort - the upward pull - and the fulcrum - the ends of the hub resting on the base's lip - at the other. Its like a wheelbarrow. The load in tension on the bolts then is a function of distance they are away from the ends of the hub and from the spigot. So the load on each bolt < 250 lbs. The other issue is unequal torquing, for which I do not have an answer. So if bolt 1 is torqued more tightly then bolt 2, the distribution of load might be different.

My bad. I meant to write load on each bolt > 250 lbs.

Alrighty then so let me start off by saying that Reykjavik and cold temperatures have nothing to do with it. Google "Craig Ferguson Capital of Iceland". He sets up every question for his "big cash prize" trivia at the end of the show with "...Iceland is in the north Atlantic, it's capital city is Reykjavic...." then asks the trivia question which has nothing to do with Iceland. Same applies to the dimensions of the assembly. I thought some of you might catch on but I guess it threw some of you off. That wasn't the intent. My lame attempt at humour. Sorry.

Although JT might have caught on since part of his posts have nothing to do with this thread either. Could be just coincidence but it was funny s!&t.

Anyhoo, the first correct answer was Passington with post #1. There's prying action going on, the load per bolt is more than 250 lb and how much depends entirely on geometry and material. It cannot be calculated to any degree and that's why the dimensions are irrelevant. JNB agreed, and for this particular case, yes the additional load is minimal due to the geometry but it can be significant as you'll see later.

The "best answer award" goes to K Fry post #9 because he elaborated on the actual mechanics of what's going on. I'm surprised I'm the only one who gave him a GA. He explained in his 2nd and 3rd paragraph how the mechanical interaction of the system components is affected by the geometry/material and how that relates to the potential for more or less prying action. In fact, I modified the model along the same line of thought that K Fry envisioned to see the difference in prying action results...prior to posting this question about intuition. The results varied exactly how K Fry thought it would. He knows his stuff. His intuition rules!!

Some others were getting close with the leverage calculations but its way more complex than that due to material stiffness considerations.

As Mr. Falconer said, it is statically indeterminate and the only way you can solve it (in theory!) is through FEA.

So that's what I did. Results are below. For this particular geometry and material (steel with 50ksi yield), the additional load due to prying action is about 32 lb. Bolt stretch (0.5" shank dia) was a paltry 0.000075". This was not enough to cause the hub lips to separate from the base pads. The hub lips had a tendency to move downward and inward since there was a rotation taking place at the outer edge of the bolt head when the hub was deforming. The hub lip was restricted from moving downward by the base pad thus causing the additional reaction load of 32 lb. The deformation in image #1 is magnified about 1000x so you can visualize it. It's not something you can see at 1:1 scale. BTW, in case your wondering what those protrusions are at the bottom of the base...nuts!

To further confirm K Fry's "intuition", I removed the pads from the base to allow the hub lip to move (rotate) downward. By removing the base pads, a gap between the hub lip and base is simulated as per K Fry post #9 paragraph 2. Sure enough, the load sensors measured almost exactly 250 lb since there was no additional reaction taking place (image #2). You can see the darker blue vector arrows forming a circle (rotating tendency) near the contact edge between bolt head and counter bore face of the hub (image #3). The hub lip moves downward about .0003" if there is no restriction.

Again to confirm K Fry's intuition (post #9 paragraph 3), I brought in the spaces between the hub spokes by reducing the cut out radius. I also brought the hub lip closer to the bolt center to increase the ratio for the lever action (image #4). Once again, the load on the bolt increased since the hub deformed more easily and created more levering affect at the lip. Loads reached 317 lb (Image #5)

So there you have it. Applause for Mr. K Fry (and everyone else who got close). We'll start making that keyboard for you as soon as we can source unobtanium. It might take a while because that stuff is really, really, really hard to get! In the mean time you can see it here full size.

The debate in our office is when to consider prying action and when to ignore it. In this particular case, the material deformation (.0003") which caused the 32 lb additional load was much smaller than a typical machined surface flatness tolerance. This implies that if the hub did not have lips and the base did not have pads, we wouldn't really know how close the contact point would be to the bolt hole center. A FE model takes surfaces as perfectly flat and that gives you one particular result in a perfect world. AISC manual has requirements when considering prying action for cases such as loaded "T" sections bolted down on either flange. But...how do we know where the contact points are if we take surface imperfections into account especially with construction grade surface finishes?

More thoughts /comments welcome.

Wasn't this fun?

Wasn't this fun?

For Sure it was

This is interesting for sure. I have a question. If you kept the spider's spoke lengths the same as the original model you started out with, but brought in the spaces between the spokes (made them flexier), how much is the variation in the bolt load and reaction load relative to the first scenario and the third scenario, where you brought the bolt holes closer to the hub? Sorry, I don't mean to waste your time in running another simulation, but I'm curious now. Much of the argument of why it is statically indeterminate is because of factors we don't know, things like the material stiffness. The other part is the geometry of the spider, spokes and the location of the bolt holes themselves. This second part could have easily been made clear. Hence, given the problem statement in the beginning that dimensions are not relevant to the problem, you should also accept the solution of many posters here that the bolt load is greater than 250 lbs. We just didn't know by how much. ;)

Ron, I happened to have run a few different scenarios including the one you suggested. I only posted the results with the most variation in bolt load. The configuration you're thinking of, spoke length per original dimension and cut out per pic #4, the bolt load was 289 lb. It increased only 7 lb compared to the original config where it was 282 lb. There was actually a configuration where the bolt load was only 250 lb and I had also kept the hub lip and base pads in contact. The configuration was pic #4 with hub ends close to the bolt but with a large radius per original config. This made the spokes very rigid. There was very little bending of the hub end beyond the bolt. In fact in was less then the amount of bolt stretch which resulted in the hub ends lifting completely clear of the base pads so no additional reaction took place. Keep in mind there was no bolt torque. It would be a different result if you consider bolt torque.

And yes, anyone who said the bolts would see more than 250 lb was correct.

Many thanks for the keyboard!

I hope to make good use of the Lynn and Solar Eagle function keys. There are some threads that I visit just to see what Lynn's response will be. We'll have to see if the function keys can accurately replicate his wit. I have some experience in AI from the early days (the "first time around") so fear that some essence might be missing: to my mind, the coffees from Starbuck's and McDonald's are not interchangeable.

But if your programming skills match your drafting skills, there is hope.

Great thread. This could be a series.

Uhm...you do know the keyboard was a joke right?...cause you sounded kinda serious there for a sec and I couldn't tell cause there was no happy face. I'm not very "intuitive" that way. Same reason I can never tell what my wife is thinking! There's never a happy face in those situations either...if you know what I mean.

"...made of unobtainium!"...can't get the stuff!

Cheers.

Uhm...you do know the keyboard was a joke right?
Yes, indeedy. I have a quite dry sense of humor, and even in person, some people will think I'm serious when I'm not. Part of the effect of dry humor is lost if the perpetrator immediately starts to laugh. (Part of the effect comes from "He can't be serious... or can he?" reaction on the part of the listener or reader.) So I'm not a big fan of emoticons -- it's little like laughing at your own joke.

Gotcha. Good to know.

Cheers.

Oh, by the way, where was it indicated in the original posting that the central shaft went all the way through the main disk, just like the bolts, which all turn out to have heads wider than their respective shafts?...

"...central shaft through the main disk" ?? What the...??

The parts in the assembly have 3 different colors...to show the 3 DIFFERENT PARTS . The shaft you speak of is one piece with the rest of the part with the same color. I thought that would be obvious...intuitively!

Guess I was wrong cause it wasn't obvious to you!

Cheers.

((Obvious)) in the original post that the central shaft does, or does not, pass through the main disk, from:

- what specific detail?;

- what view?;

- what feature?;

- what written description?;

- and/or what other means?...

It has 1000 lb pulling on it, and yet it is still there.

Much was missing from the OP, esp. many crucial facts subsequently ignored.

This is generally what happens when you have a bee in your bonnet, or an axe to grind. Preconceived conclusions are almost as good as hindsight.

Mr Guest there's no need to post anonymously. I don't take a offence to your "axe to grind/ bee in the bonnet" comment. I don't know what makes you think that. This was all for fun and amusement. If you required more information to formulate an answer to the original question, you were more than welcome to ask for specifics and I would have happily answered any question you had...but you didn't !! In fact, you never posted a single thing until the answers were revealed. Then you say there wasn't enough info to come up with an answer?? Your're not making any sense. I don't understand why you're on my case about it but hey, whatever, that's your thing.

Passington nailed the correct answer 13 minutes after I posted the question. K Fry went into a detailed explanation on the mechanics. Many others came really close. They all understood the construction of the assembly just by looking at it without me having to write a book! So why didn't you...the answer is in the thread title!

All these other crucial facts you're referring to were irrelevant because this was not an answer you can calculate. The point was to show you understood the concept.

Oh, and you should really think about Tornado's answer in #87 because it's a good one.

Just to be completely clear and accurate, I did not sign in anonymously...

You are relatively new here. Before you came aboard, there was a "Portugal Philip" who later called himself "A Guest", and often posted anonymously. To put it mildly, he was spectacularly offensive, and eventually got banned.

Your "MR. Guest" may be unintentionally ringing some old bells. After a while, this issue (if it really is one) will subside.

I don't see any issues here. My rant was direct towards the anonymous guy which I thought was Mr. Guest. It sounded like him but if it wasn't then...my bad! I never new about this Portugal Philip guy. It was before my time.

It's all good.

Yes, thank you Terraman. this has been instructive for me. (I have given a "GA
to Yesyen who correctly emphasised the additional load.)

While I did see the leverage on the bolts; from a practical use I discounted it.
i.e. by using half inch steel plate only a few inches across! My mistake to ignore it,
(shame) as the load on each bolt is seriously increased, far more than I realised.

l live and learn. (thankfully I have not under spec'd too many pipelines!)

jt.

A mother cleaning her son's bedroom finds several S & M magazines under his bed.
Upset, she immediately shows the magazine to her husband.
"Well?" his wife asks. "What do you think we should do?"

"I'm not sure," the father replies. "But we certainly shouldn't spank him".........

Two hundred and fifty pounds plus the tension on bolt (torque).

As a structural engineer I had an advantage, "Prying Action" is an official term in the specification that governs the design of structural steel in the USA; it occurs in clip angles and tees used to support hangers and similar installations. The problem does occur in baseplates with uplift and/or heavy moments too.

As a practical consideration, the bolts must be torqued or they will unscrew and drop the load, probably at the worst possible time. If the landing pad had been around the hole, or if the pad was inside the bolt ring, with no bolt preload, there would be only the weight to be considered, the piece would lift off the pad in the latter case.

Passington, its funny you mentioned base plate uplift. My reasons for posting the question was not entirely just for fun. We are actually facing this issue in our current project. I wanted to get a sense of how intuitive it is for others to see the potential for prying action in a design. The firm we are collaborating with is suggesting that we ignore the prying effect but I'm adamant about considering it. It is a requirement in AISC that it be considered in certain applications and the design of this particular component fits the bill. It's not a public structure or any type of public safety concern but a failure of this component will result in damage to a lot of expensive equipment. Our initial analysis revealed considerable prying action in the flange plate of this component. In my opinion its a terrible design but we don't have any control over it. The other firm insists that their bolt size is sufficient. I'm saying its not and that's where the arguements started. We'll see who ends up in the wrong in a few weeks. Below is a pic of the flange plate design which will be bolted to a large frame. Notice there are no holes in the flange plate on the opposite side of the vertical plate being loaded (red arrow). The bolt holes on the right of that vertical plate are 57" away. The corner of the flange plate you see actually bends up during loading by a noticeably significant 0.03"...and they say there's no prying action! Terrible design!

We'll see who ends up in the wrong in a few weeks.

Well, maybe not. Things are designed with a factor of safety, otherwise known as a factor of ignorance (not so much today as long ago due to FEA, etc) If the prying is covered by the FOS, you won't really know.

Our calcs show 2 of the bolts will snap like a twig. They're in for a surprise at load test time if they stick to their guns. I can't wait!

Which two?

The last two from the corner take the most load. It's the stiffest section of the component. Sorry, I can't show you the entire part.

Twigs break on BENDING

Bolts elongate-Yield.Never Break like Twigs .

1000lbs by 4 Structural Steel Bolts - minor dia 10 mm. yield strength>30Kgf/mm2

BREAKING like TWIGS!!!

Somebody needs revisiting Stress-Strain Curves!

Intuition???

Geez Mukulmahant!... First off all "snap like a twig" is just an expression.

Second of all...I wasn't referring to the bolts in the hub with the 1000lb load. Follow the sequence of posts. I was referring to the design a structural component we are working on with another firm. See pic in post #66. It was a response to Lehman's post #73.

Somebody needs to pay attention!

FYI, bolts snap all the time...after they can't elongate anymore!

BREAKING like TWIGS!!!

....or breaking like spaghetti? There is a difference.

Raw or cooked spaghetti? There is a difference....

You guys are relentless!...I give up. :-|

Now i'm hungry. Gonna go make sphagetti.

Yup, prying action will definitely occur with those two bolts, as loaded.....

They need to add 2 bolts behind (to the right) of the flange to reduce the prying load significantly. As it stands now, the two bolts and baseplate are eccentrically loaded.

Around 250 lbs on the THREADS of the bolt.