What is this part?

[W8BYA]

Along with a lot of recognizable nuts, bolts, etc I found a handful of these items. Any idea what they are called and how they are used? The weird thing (to me) is that the side that says 5/16" bolt is smooth bored while the side marked stretch 5/8" Drill has internal threads.

 

[sea2summit]

Jam nut. Put it in cement maybe? Drill out with a 5/8 drill, drop that in, put a 5/16 bolt in and tighten to wedge it in place.

 

[W8BYA]

Jam nut. Put it in cement maybe? Drill out with a 5/8 drill, drop that in, put a 5/16 bolt in and tighten to wedge it in place.

Weirdest looking jam nut/device I have ever seen. What end goes in the hole first?

 

[Locoweed]

End with the threads is how I would do it.

 

[Willman]

Weirdest looking jam nut/device I have ever seen. What end goes in the hole first?

Flush hole concrete anchor

 

[Thomas]

One end should be threaded that end goes in first...if using in cement make sure cement dust remove.

 

[bcp]

https://www.grainger.com/product/MKT-FASTENING-Expansion-Anchor-5-16-in-Anchor-22A673

Bruce

 

[Willman]

One end should be threaded that end goes in first...if using in cement make sure cement dust remove.

Yes, and use a washer under the bolt head, keep in tight against the surface as you tighten.
You need to drill the hole deep enough so the bolt doesn’t bottom out before it’s tight.

 

[5030]

https://www.grainger.com/product/MKT-FASTENING-Expansion-Anchor-5-16-in-Anchor-22A673

Bruce

BINGO

 

[dlctcg]

Usually called Double Expansion Anchor or Double Bolt Anchor usually used for medium to heavy loads... the threaded end go in first.


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