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Structural Blind Bolts

Structural Blind Bolts

Structural Blind Bolts

(OP)
I have some framing with WF beams mmoment connected to HSS columns. One of ideas of connection is to use the blind bolts. However, I have a lot of difficulties to find something solid about it (USA).
Have someone any experiance with this kind of connection?
HSS Manual is not very helpful.

RE: Structural Blind Bolts

As you can see, HSS is kind of cumbersome when it comes to mement connections.  Usually, the HSS need some stiffening to avoid buckling of the walls.  The beam can then either be bolted to the designed stiffeners, or welded to the HSS.

RE: Structural Blind Bolts

JohnSki,
I would stick to the normal bolts.  I have welded a plate on the face of a colum that was drilled and tapped for bolts (cap screws with full thread), but that was for a very large piece of equipment.  The beams were 1" and 2" built up box beams.  I had diaphrams inside some of the boxes.  It was not cheap to fabricate.

RE: Structural Blind Bolts

See Lindapter's Hollo-Bolt: www.Lindapter.com
Used as structural connection on tubes.

RE: Structural Blind Bolts

(OP)
Thank you all for some tips.
I called Lindapter for more info.
I understand the limitation in use, but in some cases blind bolts can be more efficient (cheaper) than other type of connection, with the sufficient strength.

RE: Structural Blind Bolts

You can also try Huck (Thiokol) fasteners.  They have many fasteners which are used in the automotive, railway and other industries that will do the job.  Ask them about BOM rivets.

RE: Structural Blind Bolts

Alcoa recently purchased Huck, so it is now: Huck Fasteners, an Alcoa business.  You can learn more at:

http://www.huck.com

RE: Structural Blind Bolts

Have you looked at expanding bolts? (known as hollow bolts in U.K.)
Another system is Flowdrill where a tool is rotated at high speed ad pushed through the steel, forming a swaged cone of material on the internal face. This can then be tapped and bolted in the usual way. Tool cost is approx $1600, but pay back good on volume.

RE: Structural Blind Bolts

Have you thought of using a friction drilled hole?  It is great for blind applications. This process is used alot in Europe, but is just now beginning be understood in the U.S.


For more check out these sites:  

www.frictiondrill.com

www.formdrill.com

www.flowdrill.nl

RE: Structural Blind Bolts

Oh, forgot to mention that tool costs for friction drills is not $1600 by earlier post.  

From my experience the drills run between $50 -$390 depending on size and type of application.  And tool life is 3,000 to 40,000 holes depending on material.

RE: Structural Blind Bolts

John, are you still looking for a solution? Have you looked at thermal drilling? This system works well. you can get more info at

www.danly-te.com

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