Need to make 2 1/2" round easy out.

[mcostello]

I need to make a big easy out for a customer 2 1/2" round x appx. 1/2" thick. What would the group recommend? I was going to heat treat with a torch so was thinking air hardening A-2 steel. The easy out would be pulled into some threads with a pull stud. The pipe flange is unknown stainless steel, the threads are shallow around 1/32" deep. The flange is in the back of a cabinet with restricted access. Back access is unlimited. It's in a clean room with no cutting or grinding allowed. I figure this would be a good place to inquire as You'all work with the different alloys.What would You recommend? Thanks, Mark.

[Charles R. Stevens]

Let’s see if we are on the same page, buy “easy out” are we referring to an broken bolt extracting tool? 

[Kozzy]

Stainless fitting?  Guessing it's galled in place as stainless against stainless has a threshold galling stress of 2000psi, half that of carbon steel pairings.  That'll mean it's essentially welded in...the unknown being how much "weld" there is between the threads of the part being removed and it's mounting plate.

That means it's entirely possible that the part will tear before it backs out with an "easy out" of some sort. Stainless is effectively very soft when it comes to tearing and ductility in the un-work-hardened state.   Make sure you consider the potential torques involved between the easy out contact points vs the locked thread so that your easy out mounting won't simply tear the stainless before it overcomes the lock.  Positive solid grab is going to be really important here.  I assume that "no cutting" means no drilling or tapping because that would be my first choice for mounting some sort of wrenching point.

You might also consider how you could possibly do this with a 2 pin spanner---again, likely requiring drilling but maybe there is an out of the box solution.  

In a nutshell, the problem won't be the hardness of your easy-out, it'll be the softness of the stainless it engages and overcoming the torque caused by the galled threads.  I obviously don't have the whole story here but I'd be pushing for ways to actually drill a couple of small holes in that clean room environment and approach it a little differently.

 

[BIGGUNDOCTOR]

This is why I hate treaded stainless joints. I have run a nut down on a 1/4-20 bolt super easy by hand and had it gall on removal. I ended up twisting the bolt in half and the nut never moved.

I would inform them that it may not come out, and if it does the remaining threads may not be usable. If so, do they have a plan B?

My first choice would be to cut a couple of slices in the fitting and try removing it in sections. I have had to do this a couple of times with pipe fittings in order to save the more expensive item.

Are they absolutely sure they know how it was assembled? Was it LocTite'd where it would need to be heated to 400F before removal? Was there any other fitting on the backside holding it? I have seen some funky installs that looked one way but were actually done differently - usually found after the part was destroyed unfortunately.

Lastly GOOD LUCK!!

[mcostello]

A 2 1/2" easy out evidently is not available anywhere We have looked. It is of no consequence if the part is damaged as they are being replaced anyway. This is in a clean room no cutting, slicing, dicing or grinding. Would make it too easy and no job for Me.