I want this massive socket as a showpiece!

[The_Eric]

One of our local parts house sales reps came in the other day showing off some impact tools from Grey Pneumatic. He left a catalog, so when I had a few moments, started leafing through it. Came across the 2 1/2" drive section! Had no clue there was such a thing. My eyes fell to the bottom of the page to find an 8" socket!!! I took the number down and had him look it up for me, just for kicks... The price? $3921.93!!!

Two things that I'd like to see are the gun that runs this socket and whatever that bolt is holding together...

Huge Socket. Notice the published weight... 95.6lbs!

 

[JHZR2]

Wow. That's how you take ships apart.

 

[daves87rs]

Wow! Cool!

 

[ledslinger]

I think that's the size for the Jesus nut on helicopter rotors.

 

[artificialist]

What do you use to properly torque an 8 inch nut?

 

[OVERKILL]

Originally Posted By: artificialist
What do you use to properly torque an 8 inch nut?


Probably something that mounts on the end of an excavator's arm

 

[Donald]

I will wait for the HF version. It will be only $34.99, on sale for $19.99, but currently out of stock. Obviously a lot of people need to tighten 8" bolts or nuts.

 

[JTK]

LOL! We've got a ~4ft long extension for 2.5" drive sockets at work. Never did see the sockets that it was used with. It's only use now is to slide into a big receiver tube that allows us to change the position of a 4-way valve system. Like a big ball valve quarter-turn swing.

Joel

 

[George Bynum]

Originally Posted By: artificialist
What do you use to properly torque an 8 inch nut?
I am not sure your question is serious, but assuming it is, I'm accustomed to 2 ways. One is a hollow stud in which a heating element is used to obtain a defined "stretch", the other has a special end where a hydraulic bolt stretcher can be used. I don't know which is preferred for what applications, but steam turbines are assembled with the hollow studs, and many pressure vessels with the bolt stretching gizmos.

 

[oilboy123]

I know the last time I was at the Space Needle that it had some pretty big nuts holding the frame down.

 

[Shannow]

Originally Posted By: artificialist
What do you use to properly torque an 8 inch nut?


You have to use stretch, as was previously mentioned.

Take a 39" long 5-1/2 UH (8 tpi) turbine bolt. You will have one diameter engagement in the body, and one diameter of engagement in the nut if the joint is designed properly, giving a "working" effective length of 39"-2x5-1/2, or 28".

First you "finger" tighten to 200 lb ft, just to seat the nut.

Then heat the stud to stretch it, or use a big hydraulic puller to stretch it so that there's a clearance under the nut.

You then typically want the stud under 0.15% strain when cooled and clamped, so you calculate 0.15% of 28", which is 0.042" (about 1mm).

360 degrees of rotation is 1/8", 0.125", so 0.042" = 0.042*360/0.125 = 120 degrees.

Turn the nut 120 degrees, and let cool, or undo the hydraulics...that's properly tight.

Same calculation for bolts that are tightened without stretching, although anything over 2-1/2" is pretty hard to get through the angle of tightening, and anything larger twists the stud too much to be accurate.

 

[Shannow]

We've gotall of this sort of stuff on turbines
http://www.hytorc.com/

Watch the video on this.
http://www.pilgrim-international.co.uk/

 

[kkreit01]

Holy cow! I saw a 2.5" socket, and thought that was big.

 

[Donald]

Who makes a 2 1/2" drive cordless impact wrench for this massive 8" socket? Would that be Dewalt or IR?

 

[The_Eric]

Originally Posted By: George Bynum
Originally Posted By: artificialist
What do you use to properly torque an 8 inch nut?
I am not sure your question is serious, but assuming it is, I'm accustomed to 2 ways. One is a hollow stud in which a heating element is used to obtain a defined "stretch", the other has a special end where a hydraulic bolt stretcher can be used. I don't know which is preferred for what applications, but steam turbines are assembled with the hollow studs, and many pressure vessels with the bolt stretching gizmos.


Originally Posted By: Shannow
Originally Posted By: artificialist
What do you use to properly torque an 8 inch nut?


You have to use stretch, as was previously mentioned.

Take a 39" long 5-1/2 UH (8 tpi) turbine bolt. You will have one diameter engagement in the body, and one diameter of engagement in the nut if the joint is designed properly, giving a "working" effective length of 39"-2x5-1/2, or 28".

First you "finger" tighten to 200 lb ft, just to seat the nut.

Then heat the stud to stretch it, or use a big hydraulic puller to stretch it so that there's a clearance under the nut.

You then typically want the stud under 0.15% strain when cooled and clamped, so you calculate 0.15% of 28", which is 0.042" (about 1mm).

360 degrees of rotation is 1/8", 0.125", so 0.042" = 0.042*360/0.125 = 120 degrees.

Turn the nut 120 degrees, and let cool, or undo the hydraulics...that's properly tight.

Same calculation for bolts that are tightened without stretching, although anything over 2-1/2" is pretty hard to get through the angle of tightening, and anything larger twists the stud too much to be accurate.


Thanks for info guys. Very neat to learn about this type of stuff.

 

[scurvy]

Originally Posted By: Shannow
Then heat the stud to stretch it, or use a big hydraulic puller to stretch it so that there's a clearance under the nut.


When I worked for GE's steam turbine repair shop, we always used hot rods through the center of the bolts. Most of the nuts were castellated as well but I never saw any locking devices nor would one be necessary once the joint cooled!

 

[tom slick]

I've used a Sweeney multiplier on high torque stuff:

It's rated to 12,000 ft-lbs