I'm trying to understand bolted joints better. For reference, this is from Shigley’s.
Conceptually it makes total sense. And it is obviously right especially because it's in THAT book. But when I try to test it myself some contradictions appear and I can't understand what's happening.
First...
Trying to calculate the maximum stress that would occur in the attached assembly...
The assembly consists of a tube sandwiched between two plates that are bolted down to a larger plate with an M6 bolt. Each of the two plates have a 400N force acting on them which is perpendicular to the axis of...
Say I have a bolt and I thread it into a threaded hole. If I torque it down to a certain torque, then use a paint marker and mark the head of the bolt and the surface that the threaded hole is in with a straight line. Then I unfasten the bolt and refasten it into the same exact hole, and torque...
Hello all,
In a recent discussion, I came across this question of influence of free length (or unthreaded length) in bolts in retaining the clamping force between the elements to be joined. Out of the two proposals in the attached pic., which one will keep the two plates clamped for a longer...
Hi,
I'm working on a simple FEA involving a preloaded bolt:
The bolt is modeled as a single part (shank + head + nut), glued (perfect bonding) to both rings. Pretension force ##F_{preload}=200 \ N## is applied in the first step of the analysis while in the second, pretension force stops...
i have a question. I have set up an expierment and need some values.
I have a round, 3d printed disk, 0.25 inches thick and 4 inches in diameter. In the center, i have a eye-bolt attached. I have hooked up a chain to the eyebolt and some weight to the chain.
I have 40Lbs hanging right now and...
Hi all,
I have some detailed design work coming up designing bolted/pinned interfaces, so I’m doing some examples trying to remember what I learned at uni. I would like to calculate the stresses in bolts and pins of a hypothetical mechanical assembly, but I have a question before I get started...
If I torque a thread combination of M26x1,5; in brass material, with 90 Nm.
Length of threds are 12 mm.
Will the torque to unscrew the parts be equal, higher or lower?
Why?
I need advice how to calculate thread pull out in aluminium 6063-T6.
12 bolts screwed into an aluminium plate (thread depth 25 mm) must withstand a load of 350 kg.
Thanks in advance
So this is for my car. If I have a bolt that I don't know what the ideal torque is supposed to be because the manufacturer of the car doesn't publish a torque, it's possible to calculate it? This can be done just give the specification of the bolt? Regardless of what the bolt is fastening? I'm...
Hello,
I have designed a gearbox that bolts on to a fixed engine and fixed pump. It is completely supported by them. The total mass of the gearbox and the components attaching it to the engine and pump is 7.7kg. Its centre of mass is 0.167m along the x-axis and 0.09m along the z-axis from the...
Homework Statement:: If you have a 1" thick steel plate (A36) with a 1.125 hole (supported at 3" half way around), what is the maximum weight that a 1" grade 8 bolt can support using a 2 to 1 safety factor. The weight is applied directly the the bolt
Relevant Equations:: dunno?
it's been 24...
The question is to determine the force in the small opening, delivered from the 250 N on both sides of the plier.
i tried multiple things but can't get the answer right. Anyone that could help me?
This is my work so far:
Hi everyone,
I have a question about sizing a bolted joint. How to calculate the size of the screw? Knowing that the bolt material is 316 stainless steel and the thread material where the bolt will be bolted is 6061 aluminum. This screw will be pulled at 2000N.
Thanks!
The robot weight is 900kg
I have a robot with max reach swinging around with a weight of 110kg at the end at 125 degree/s
I am not sure if the anchors I use are strong enough to hold it down assuming i mount the robot at the centre of the mounting plate
Any advice with doing calculations to do a...
Hello, thanks in advance.
I'm trying to make a near 100% solid carbon fiber wing. I'm vacuum bagging the top half of the wing and the bottom half of the wing separate.
After making sure there is a thin 2mm gap b/w the center of both halves the goal is to put a very strong, thick epoxy between...
Hi all,
I need to convert a cooling fixture from a weighted system to a plate and bolt system. I'd like to use 4 - 10mm cap screws and a pressure plate to replace 7.82kg of weight. The weights are 190mm x 70mm of contact area. The pressure plate will have flanges to accommodate the bolts...
Hi guys,
Bringing myself back up to speed with bolt tightening, would really appreciate if anyone has some resources or answers to these questions:
1. The proof load for torque tightening, and proof load for tension tightening
2. Main advantages and disadvantages between the two
3. What is...
When a lightning bolt strikes the earth, the air molecules are turned into plasma which causes the "light" that we see. What happens to the plasma air molecules after a lightning bolt? Do the positive/negative charged molecules find free electrons in the air and resume to be neutrally charged...
Hello,
Are there any fasteners that can be fit instead of normal screws and bolts and can be secured/unsecured via foot?
I was thinking something that you step on and it secures and you then use a lever or handle to unsecure it.
Is there anything like that?
Homework Statement
A Bolt is in single shear and is tightened so that it exerts a tension force of 60kN, the diameter of the bolt is 25mm and the shear loading is 40kN; Given that the tensile stress should not exceed 350N/mm2 and the maximum shear stress should be taken as 60% of the maximum...
I have 1" aluminum rod and I want to dril a hole in a steel structure for the bolt.
If I have a 1" drill and take .001" inches off of it at the machine shop, so that it is now 0.998 inches, there will have to be about a 200°C difference in temperature between the two articles (aluminum...
I am unable to find any paper or book on Kerr-Bolt solution. I need to know its derivation. Please if anyone can suggest some material on it? I will be very thankful.
A 5m tall elevator travels uniformly up an elevator shaft at 8m/s. At some point in time, a bolt falls from the top of the elevator and falls freely down the shaft. You can ignore the effect of air resistance.
How many seconds after the fall will the bolt pass the bottom of the elevator?
y=yi +...
Hi,
I'm looking for some help regarding working out the tensile strength of a M8, grade 8.8 bolt and the pull out force.
What information do I need to gather regarding the bolt and the material the bolt is engaging in to?
Thanks,
I ran 60 meters in 8,53 seconds today, but the thing is, I don't work out, I just started my growth spurt (I'm 160cm tall now but my doctor predicted I'll grow to be 185cm tall) and my body fat percentage is probably near 15%.
I calculated what nu speed would be if I was 185cm talk but without...
I am wondering why the material thickness is not factored into calculating bolt shear strength in a joint. I know that it is used when calculating the strength of the material itself and its susceptibility to deformation and tear out but why not the bolt? When you cut a piece of cheese you use...
Homework Statement
A hanger is fixed from the ceiling by using 4 bolts. The diameter of bolts are d=20.752mm, and load is equal to P=2kN. Determine normal stress of 4 bolts
why the Pa= +300N(upwards) is?
i think it should be -300N(downwards) like my solution(below).
and
Fa = 500 - 300 =...
I have been attempting the Solidworks Simulation certification but keep just missing out by a few marks and I believe these questions are the main ones which are killing me.
I haven't done these calculations in years and I've been lost with how to do the hand calc's. Any help would be appreciated.
Homework Statement
In this problem , why the author use (30x10^3) /s = VQ / I only ? Shouldnt it be 4(30x10^3) /s = VQ / I
Homework EquationsThe Attempt at a Solution
I said so , because the board at the centered is connected by 4 bolts , 2 on the left and 2 on the right . The faces on the...
Why does a bolt of lightning crackle into many different directions when it travels to the ground?
Can a bolt of lightning be made to travel in straight direction, is it theoretically possible to understand and control lightning?
Hello, I have a final tomorrow and I am having a difficulty to understand the heat treatment subject. I would be happy if someone can explain this question or suggest a good document shorter than Askeland (i know it is very good but there is no time unfortunately). Thank you.
Two different high...
Hello, I was recently onsite in the Philippines and the equipment owner stated their wind turbine had been hit by lightning. The only obvious damage was to the bolted connections at the root of one blade. One was sheared, the other bent. Does anyone have any experience of lighting causing...
Homework Statement
In an Effort to tighten a bolt, a force F is applied to the end of a wrench that has a length L perpendicular to the wrench. If the bolt itself has a radius of b, how much force is applied to the bolt
Homework Equations
∑τ=RFsinθ ΣF=ma ∑T=Iα
The Attempt at a Solution
I...
Hello,
I have an installation tool (which basically consists of a standard long bolt and nut) and a 100 lbs mass object would drop onto it (as if it were a hook) from about 1 - 2 inches. There are many forces to consider and I am looking into that. Since this installation tool will be...
Hello all,
I am trying to remember (I did it in Uni) how to calculate the effective mean radius of an annulus that contains a pattern of holes on a PCD.
Consider the following image (pinched from: https://www.solenoid-valves.com/ ):
If one was to vary the value of PCD, then the effective...
http://imgur.com/Wa8GR7H
Hey guys, I just would like to ask simple questions about forces/stress of aluminum bolt to be fastened for connecting aluminum extrusion as shown in diagram above.
1. As shown in the drawing, "A" shows the shear, so what force does B have then?
2. So how would you...
Please find the attached (http://s23.postimg.org/ropds44ob/Capture.jpg). I know how to get the shear force for each bolt using bolt analysis. But I don't know how to get the tension/compression force of the bolt when it position is not symmetric.
*I already download some excel from internet...
*Note: Even for 1 answer for any of the question, I am highly appreciate it. I am understand it quite a burden to answer all. Thank you.
Hi guys,
I am currently seeking a correct approach of getting the reaction force developed on bolt due to the Forward or Upward force experience by the...
I think I have solved my problem for a friction force between a bolted assembly, or at least I think did. If a torque was given of 267.6 in-lbs and a constant of k=0.2 and the diameter(d) =0.5,
T=k*P*d should equal 267.6=0.2*P*0.5, resulting in P=2676lbs.
Then using the equation:
Tc=F*fc*dc/2...
hello.
I have a ejection mold (steel) which has a bridge like mount which locates the handling eye bolts outward around hydraulic cylinders. I need to make sure the bolts in the bridge will not shear due to the sideways load when the mold is lifted or flipped 90degrees. Here is the known...
Hi,
I tried to find design regulations/codes that specify relations between bolt diameter/bolt length against connected plate thicknesses. I couldn't find that in Eurocodes 3. Can someone help me with info where to find those regulations ?
Example: can we connect 5 mm plates using M24 ? or...
I understand there are a variety of forces that are at work when a bolt is clamping two components together. However, what I don't understand is what forces are at work when a bolt is screwed into a blind hole and it bottoms out. Assuming a torque is applied, how would this torque act on the...
Hello.
I know what follows seems like a HW problem, but it's an actual problem I'm trying to solve with some equipment I will be using.
I am concerned that a bolt I am using will be unable to withstand the forces that it will face, and so I am trying to solve the problem out mathematically as...
Hi All.
I am not sure if this is the right section for this but I will ask anyway. I am looking for a bolt that pivots midway like a hinge. I have seen them before but I don't know what they are called and cannot find any on-line. Alternatively does anyone know of a pivoting pipe?
Can anyone...
I have a tapped hole. A threaded rod goes through the hole. A single nut secures the threaded rod in position. Only one plate is threaded. Note the clearance hole in the top plate. A picture is attached.
A friction joint in a bolt occurs when the clamping force creates a normal force. This...
Question about moments and torques.
I understand that torque is defined as τ=Fs and understand where this comes from mathematically but am wondering why does nature make it easier to put a greater torque on an bolt with a longer lever.
The only real explanation I can think of is by...
I am trying to design a breakaway Bolt, is there an equation to calculate how much torque is required to break the head of the bolt. Typically this bolt has two heads, one that breaks off and the permanent one. These are connected with a small neck that breaks at a given torque. That's what I...