Rolling mill stands Quick release coupling corrosion

[Mech2325]

Hello,

I am writing this thread regarding a problem I am facing at my work. I am working in a steel rolling mill. Our quick release couplings being used for air oil distributor on rolling stands are made of stainless steel. These stands are water cooled for avoiding the roll pass from excessive heat.

Our quick release couplings (specially the ID of the socket) is being subjected to corrosion which results in the sleeve getting stuck and not allowing the plug to properly couple with it.

My question is that why do these couplings get rust when they are made of stainless steel material??
Using WD 40 often removes the rust but is there any reason why does this occur or what material should we use to avoid frequent QRC's getting out of order?

 

[Jboggs]

I'm no expert, but I would guess that the corrosion you see might be an accumulation of minerals and other elements from the water itself. Check your water quality. Do a chemical analysis. Is it actually ferrous rust? Or is it some other material? Are you really sure that the socket is made of stainless steel?

 

[TimSchrader2]

We use tef gel on stainless removeable parts in Ocean air, which may be ovrkill for this application.

 

[EngineerTex]

I assume that you are using a corrosion inhibitor in the cooling water. First, check with the supplier of the corrosion inhibitor you are using. They will probably have a recommendation.

Engineering is not the science behind building. It is the science behind not building.

 

[EdStainless]

If it really does wash off then they aren't corroding but being fouled by solids in the water.
There are many reasons why this debris will selectively deposit.
It does sound like you need to re-visit your water treatment since this same crud is likely coating the inside of everything that you are trying to cool and reducing flow and heat transfer.

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P.E. Metallurgy, Plymouth Tube

 

[MintJulep]

Rolling mill = airborne steel dust.

 

[Mech2325]

Thank you all for your replies

I also want to know what is the widely accepted code or standard (if any) for roll pass design (recipe, determination of number of stands, roll gap, bite angle etc) for production of round bars in an automatic rolling mill.

 

[arunmrao]

@Mech 2325. For all those questions, you will need an experienced consultant to guide you. It is not easy.

"Even,if you are a minority of one, truth is the truth."

Mahatma Gandhi.

 

[EdStainless]

Roll pass designs are a matter that each mill decides for themselves.
This info is usually considered proprietary as it impacts production costs.
Start by talking to the equipment builders. They will want to know the alloys and size ranges.

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P.E. Metallurgy, Plymouth Tube

 

[Mech2325]

Thank you once again for your replies

I have the pass design at the mill but I want to know the basis of it

If anyone here can help

I am not asking to share your mill's recipe
Just any good book anyone here recommend or a rule of thumb for calculating these things

 

[Pete_K]

The only books i'm aware of are the Roberts books.