Bolted Joint Stiffness: Spring Constants of Bolts and Clamped Members | Joint Stiffness Constant

[@Felipe-53]

Sir, your lectures are of so much help. You go into the details the book doesn't and the presentation is so clear. You're an awesome educator! Thanks for sharing with us!!!

[@TheBomPE]

You are always very kind. Thanks for the positive review and encouraging words!

[@kinat562]

best video for nut and bolts, everything is clear now

[@TheBomPE]

I'm glad it helped! Thanks for watching!

[@dogansahutoglu2073]

a profound lecture relative to joint stiffness in bolts. Thanks Micheal.

[@TheBomPE]

You are always very complimentary... thanks for the encouragement!

[@chenuka999]

One week till exams. So luckyI found this video! You explain better than my professor. Thank you so much!

[@TheBomPE]

I'm glad I could help! I hope your exams went well!

[@AJ-et3vf]

Great video about bolts! Very clear, procedural and quite helpful!

[@TheBomPE]

I'm glad it helped! Thanks for watching!

[@The_Raylle_Red_FK8]

These lectures are phenomenal! Unfortunately my teacher for this class can't explain these topics to save his life and it is making it very difficult to learn these topics. Thank you for explaining so clearly and making it so simple!

[@TheBomPE]

I'm sorry to hear your experience is not going so well in your class, but I'm glad I could help! All the best to you!

[@b3dubbs72]

Thank you for going into so much detail. Our professor just skims over a PowerPoint and doesn't really explain all the different variables with subscripts, which in this class gets very daunting.

[@mrcoffee315]

What if there is a gap between the two materials you are clamping together? for example two plates and a cylinder is being compressed by the plates with 4 bolts and the second plate has a through all thread

[@agostinoscanu5456]

Any chance you wanna move to florida and teach at FAU? our machine design prof is not so great.... wouldn't be surprised if you got the job without an interview. These videos are proof of your excellence!

[@TheBomPE]

You are very kind! I kind of like the idea of moving to Florida... hmm... Really it's my wife you'll have to convince :)

[@pasta_pie]

thank you so much for uploading your lectures they are awesome! it would be a great idea to upload the note you are taking to the description, but in any case thanks Micheal!!

[@edwardkersey2771]

Very thorough. Thank you very much!

[@asifanwar2057]

Wow! Learnt a quite new things. Thanks.

[@TheBomPE]

I'm glad it was helpful! Thanks for watching!

[@goriaakash]

Way better than my prof, graduating on april 29th 2022

[@tmw6651]

This is an incredibly useful video, thank you very much. 1 Question - where would you start the frustum when using a flange head bolt? Would you use the dw for the flange or the base of the A/F for the bolt head?

[@engineerbro912]

Helped. Thank you Sir ❤️

[@TheBomPE]

Nice to know I could help! Thanks for watching!

[@Emperor90201]

Thank you so much for all the information, sir. Two questions: 1. Where can I find information about the same type of failure analysis but in reference to common screws ( ie #12-24 size which don't use nuts)? 2. For such screws, how can I decide what thickness of material I need for reinforcement when fastening separate pieces together?

[@cauldronrevs6951]

Very nice and clear thanks a lot

[@TheBomPE]

Glad to help! Thanks for watching!

[@alperturna4371]

Hi, your lectures and the way you teach is just awesome! I think other instructors should watch your videos too. Most of time, lecturers are saying that their job is not teaching. They say that we students have to learn it by ourselves. Then what is the point of going to school ? Again, thanks a lot!

[@TheBomPE]

I'm glad you're enjoying the videos! Thanks for watching!

[@crazykillato]

For a fully threaded bolt, I would assume we just use k_t as the main spring constant for the bolt. k_b = k_t. Curious since at my job we typically use fully threaded bolts (Curtain Wall)

[@TheBomPE]

That's correct. Thanks for watching!

[@TheBomPE]

If you found this video useful, consider helping me upgrade the old tablet PC I use to create these videos! Thanks! www.gofundme.com/help-replace-my-2011-tablet-pc

[@asadmaqbool9629]

Today is my paper and i don't this topic. Thanks for your kind help.

[@TheBomPE]

I'm glad you found it helpful! I have two courses that I teach out of this text (Shigley), and I have a good number of videos presenting this material, organized into these playlists: MEEN361: kzbin.info/aero/PL1IHA35xY5H5AJpRrM2lkF7Qu2WnbQLvS and MEEN462: kzbin.info/aero/PL1IHA35xY5H5KqySx6n09jaJLUukbvJvB If you haven't already seen them, you might want to check them out! Thanks for watching!

[@syedazad9939]

Sooper... just I wanted to ask how we can calculate the centrod, if the force is acting parallel to the nut's length instead perpendicular to the nut's lenghth.

[@Giuseppe_coachgius]

Any example when bolts clamp two timbers together or a flitch beam? Timber would likely limit maximum bolt torque and so clamping force?

[@eareastchan2414]

the vedio is extremely helpful, and i am wondering the name of the sofeware at 1:03:18 ? cheers!

[@abedalrazzaqaljammal9977]

sir thanks for helpful videos its make the material much easier. may i ask if you can suggested problems from the book for each chapter?

[@phillipmaser132]

Very Nice Videos.... Mechanical design has its complexities. Do you have a copy of the text book you working out of...?

[@xgamer2011]

Thanks alot sir for this amazing lecture

[@TheBomPE]

I'm glad you liked it, thanks for watching!

[@Arunkumar-mg9uz]

Where did you learn t all this sir. Great lecture.

[@jadugar3326]

Hello sir...thanku so much for such kind of videos..sir.i have one question can i ask.. Is there any formula for a perticular torque,the no of minimum threds required??simple i have a shaft of thread size M8 which has been broken at 30 N.m torque..how can i solve it,.how much tensile strength is required for sustain this torque..

[@iftekharrousseau493]

awesome lecture!!!!!!!!

[@TheBomPE]

Thank you! Thanks for watching!

[@RahulKumar-pw4nd]

can you tell the name of the book you are using?

[@TheBomPE]

It is Shigley's Mechanical Engineering Design, 10th edition. Thanks for watching!

[@vdviniciusdalmolin]

One question: When we are calculating the frustum for the blue section of the system, shouldn't we consider the "d" of the blue section equal to the "D" of the green section? I could see that in the math cad equation the "d" used for the blue section was the shank diameter. And then the "D" would be the same "D" of the yellow section of the drawing. Thank you for the lectures. They are great!

[@rens0144]

Like the orange, bold but he owns it.

[@TheBomPE]

They say it's the new black.

[@adhithasimhanraghavan7516]

The bottom-out of a bolt engaged with nut should be atleast 2 times pitch.. which means, bottom surface of the bolt should come out by 3mm for a bolt with 1.5mm pitch

[@TheBomPE]

What standard are you citing?

[@ravijawaniganayake6111]

can these values be used for finding the dispalcement occured on the bolts, whereas F = kX will be used. PS. Great video. Good Luck

[@evgeniysklyarenko6735]

Thanks to the author for useful lectures. However, the propagation model is inaccurate in this case. Everyone takes into account that the bolt is stretched due to the force, but they do not take into account that the metal is also compressed between the bolt head and the nut. Due to this compression, deformation of the plates occurs and outside the compression zone the plates tend to move away from each other. This phenomenon is of great importance for the propagation of forces from the bolt. This phenomenon will be clearly seen if we take plates of smaller thickness.

[@TheBomPE]

Perhaps if you watch the video again you may pick up on the parts where I show how the material between the bolt head and the nut are compressed. It's approximately half of the video.

[@evgeniysklyarenko6735]

@@TheBomPE Let me once again discuss the issue of the distribution of force from the bolt. It means a lot to me. Perhaps I did not express my reasoning very accurately for the first time. Compression of the anti-slip joint plates under the action of the bolt tension force in the projection area of the nut and the bolt head, bending at the boundary of the projection area, reducing the interaction of contact surfaces outside the projection area. As a result, the main force perceives the circle in the projection zone, the remaining part of the circle around the bolt hole is practically not involved. This phenomenon is very well seen when thin plates are bolted together, deformations become visible and irreversible. If you tighten one plate with a bolted connection, this effect does not exist, but it becomes obvious when two or more plates act on each other. Photo 1 disk.yandex.ru/i/LKv2YIWcpnEiZw Photo 2 disk.yandex.ru/i/VBe-MEJzltztpg In photos 1 and 2, the plate is subjected to a load of 10,000 pounds. The bend occurred away from the base of the press. Please tell what you think about this phenomenon and the effect on the distribution of forces from the bolt tension.

[@herzaryo1340]

Sir, what textbook do you use as a reference?

[@TheBomPE]

I use Shigley's Mechanical Engineering Design, 10th edition. Thanks for watching!

[@herzaryo1340]

@@TheBomPE thank you sir

[@phillipmaser132]

Now, that you have the joint stiffness... we know what the bolt load is 19%... Lets say I apply a pressure on top of the clamped member structure. How is this force added into the equations. Washers is another fulcrum. Pressure is a force... I am thinking we would need a math model here. I want to apply a 25K PSI force here and see what happens. If the bolt breaks, I need a way to find new bolt here with a pre-load condition that would work?

[@guilhermeferrari3756]

What are "rule of thumbs" ?

[@TheBomPE]

It's a figure of speech.... en.m.wikipedia.org/wiki/Rule_of_thumb

[@guilhermeferrari3756]

@@TheBomPE Thank you :)

[@cyrusIIIII]

D is the narrow side of the frustum but when you were calculating the stiffness of the blue portion of member, it seems you added 2a to it! why is that?

[@TheBomPE]

the overall shape of the frustum extends through the whole grip, but because there is a change in elastic modulus between steel and cast iron, that blue portion has to be evaluated separately. The length "a" is the additional radius that is needed to find the narrow-end radius of the blue portion relative to the radius where the overall frustum begins on the washer-face of the nut. (This is what I mean by what I'm saying at about 1:01:23 .) The "D" in the formula is the diameter of the narrow end of whatever portion of the frustum is currently being evaluated, so we are trying to find the diameter of the narrow end of the blue portion. Thanks for watching!

[@cyrusIIIII]

Is capital D washer diameter or washer face diameter?

[@TheBomPE]

D is always the outer diameter of the narrow end of any frustum. This is the washer face diameter where the bolt head or where the nut contact the material of the grip. The washer diameter is seldom a value we care about for these calculations (as long as the outer diameter is at least as large as the washer face diameter, which it generally is).

[@tauqirkhan876]

Nahin aisos?

[@TheBomPE]

I only speak english.

[@tauqirkhan876]

@@TheBomPE okay i got it

[@meharsamba]

Height of 17/64...seriously....? Americans will overcomplicate but refuse to use metric...

[@TheBomPE]

Everybody has a perspective.

[@meharsamba]

@@TheBomPE ah well...all i can do is convert them to metric to learn..lol

[@armandmatossian2081]

Who cares about stiffness. I would like to specify a bolt that will prevents two objects from separating without yielding. How hard is that? Why isn't that taught in school?

[@TheBomPE]

kzbin.info/www/bejne/q5-0l3Rrm66Miac

[@armandmatossian2081]

@@TheBomPE Thank you so much!!