bolt without Nut 2

[saad73joss]

Hello gentelmen,
I have a case where I can not place a Nut in the other side of a bolt. Is the capacity in tension reduced or not ?
many thanks in advance

 

[ukengineer58]

think you'll need a propietory system. search hollo bolt on google

 

[Ron]

Yes. Do not weld the bolt. As ukengineer notes....use a proprietary system, preferably one with test data to which you can compare your loads.

 

[saad73joss]

Hello Ukengineer
It s good to know. really good
But still I m wondering in case we have no Nuts, what is the capacity in tension of the bolt. does it remain the same even without the nut?
thanks

 

[PMR06]

The tension capacity of a bolt with no nut is ZERO.

 

[kingnero]

unless it is threaded in a mating part...
which needs to be calculated again, depending on material, number of threads, ...

 

[TehMightyEngineer]

Do you mean the that the two plies are in tension, putting the bolt in shear? Otherwise it's clearly no capacity as PMR06 states.

Maine EIT, Civil/Structural. Going to take the 1st part of the 16-hour SE test in October, wish me luck!

 

[rb1957]

how about using a stud (into a threaded hole) ?

why no nut ?
'cause you can't access it (maybe use an anchor bolt instead ?)
'cause there's no room on the far side for anything to protrude ... what's the material ? can you thread it ?? can you counterbore the far side to recess a nut ???

 

[saad73joss]

As mentions M. Kingnero, I want to use the threaded part
I attached a picture
Actually I have to calculate whether the number of threads is sufficient or not
If so I have no idea how to calculate the capacity of a thread, any help!

 

[TehMightyEngineer]

Per your picture you show the bolt passing through both plates fully. If either or both are threaded then you must account for that. However, by the nature of threaded parts, as long as your threads are drilled and tapped properly it will be simple shear.

Calculate your shear length as the circumference of the hole radius minus 1.5 mm for the distance between the bolt and the threaded hole. The shear area is then that length times the thickness of your threaded plate. Multiply that by 0.6 times the yield strength of your plate (13th AISC equation J4-3) and divide by your safety factor (1.5 if using AISC ASD). This is the capacity of the threaded part, you'll need to check the bolt capacity but, assuming your plate is A36 steel, it will likely not control the design. There may likely be other requirements such as deformation of threads that must be checked but this will give you the most basic capacity of the part.

Maine EIT, Civil/Structural. Going to take the 1st part of the 16-hour SE test in October, wish me luck!

 

[saad73joss]

Many thanks The MightyPirate

 

[dhengr]

Saad:
Look in most any good Machine Design text book or try “Machinery’s Handbook.” They cover this at some length. Whatever the strength of your bolt and of your plate, you can adjust the thickness of the threaded plate to match the strength of your bolt. Otherwise, TehMightyPirate has it right. But, you can adjust (play with) a few of his numbers in small ways.

 

[rb1957]

this looks like a concrete anchor, no?

looks like it needs the industrial equivalent of a rawl plug ...

 

[saad73joss]

Dear rb1957
It s a simple bolt connceted to the plate through threads without nuts
The rawl plug is like Hilti in Europe
Thanks Dhenger and all of u guys

 

[rb1957]

uk's first post (hollo-bolt) would work.

drilling a hole and "potting" some sort of threaded insert (like a rawl plug) would work.

if you can access from the side ... drill a horizontal hole to intersect your vertical hole (for the bolt shank) and insert a "cross-pin" (that would intersect the bolt shank in the horizontal hole and restrin the bolt against the concrete.