How to remove a collar from SS sharft

I have a problem which is to remove a keyed bronze collar from a stainless steel keyed shaft. I can not get the key out either and there is no sign of bad corrosion

So far I have applied WD40 type products and firm hammering over a few weeks now and no progress.

I have thought of applying heat but not sure if I may cause other problems.

Any advice would be appreciated. Thx

This is it ie an electric anchor winch, it can just be seen the key into the shaft on the left side

Looks like the key is normal steel and the rust has expanded tightly in the groove.

Try wacking the bronze collar on the face where the key is with a sharp wack with a hammer (only once or twice) and hope that this will induce cracking in the rust and thereby releasing its grip.

Alternatively try a product like Loctite Freeze & Release, this has a similar effect as heating but without effecting any heat treatments that may be present.

If all else fails and there is no heat treatment to worry about then apply a bit of heat to the collar using a fine flame torch to keep the heat as localised as possible and once again a quick wack with a hammer to shock the rust into releasing.

As previously stated WD40 is crap and causes more grief than it solves as people think something they have squirted with WD40 is now protected.

1) Its left field but I've seen it work.
Liquid nitrogen down the centre of the shaft , will contract the shaft and crack the join.
Then bash with hammer.
Its a fiddley chemical to get but not expensive.
Air liquide or any of the gas places for the nitrogen.
Can use any metal thermos flask for holding the delivered nitrogen.
Do not seal the thermos with the lid (would be bad) , allow evaporation to occur , perhaps a hole drilled
in the top of the lid.
We normally pay about $80-100 for a delivery.

2) another option is a can of veruka spray from the chemist, its only about a 1/3 or 1/2 as cold as the nitrogen, but comes
in a can. Spray down the sealed shaft centre. Cold should contact the shaft.

3) another option would be to soak in CLR for a day or so. cheaper and easier but far less effective.

Given all the information offered above, there is not much more for me to say, except good luck and hope you get the job done.

Select to expand quote

warwickl said..

Thank you all for your input, I will now go try a few of these methods.

I think that you will have to build a hefty bearing puller type device with hammer in wedges to provide pulling force. Then rapidly heat the collar with an oxy torch untill it is just about red hot. Then wack the wedges with a large engineers hammer to try and dislodge nthe collar. Keep a bucket of water and wet towels handy to stop the deck from catching fire.
Otherwise I give you next to no chance of removing with earlier mentioned techniques.

If it isn't something you need to be able to do at sea, give it to a professional you know and trust. It is probably worth paying for a couple of hours of their knowhow.
My view is to make sure you can do any maintenance that could be required at sea, the other stuff can be given to a professional after you have exhausted your skill set and tool kit.