Rust on Stainless Steel
Dear all,
First off I would like to thank everyone for their contributions to this forum. I have found so much valuable information. :) Thus, I am hoping to get some advice regarding the removal of rust from stainless steel.
Some details:
-the surface we have found rust is on a non food contact surface of stainless steel 304.
-we believe it is due to iron contamination from cutting equipment or other tools used during the manufacturing of the equipment -- i believe the technical term is "Rouging"?
My question is if anyone has come across this and if there is a "food safe" way to remove this rust. Perhaps with a cleaner/solvent? The hope is to remove the contamination so that the aesthetics and the smooth surface of the stainless steel can be restored.
Thank you in advance,
James
Dear JamesT,
Unfortunately it sounds like you have acquired some stainless steel of quality insufficient for yr application.
It is no accident that 316 Grade is often specified for certain equipment / situations.
These discussions may give you some ideas on possible solutions although the procedures appear far from simple in some cases. -
http://cr4.globalspec.com/thread/81340
http://cr4.globalspec.com/thread/40455
Rgds / Charles.C
Hello,
we had similar problem caused by welding of stainless plates with electrodes which are not for stainless steel.
There are some products which like Antox 71 http://www.qwpinc.ne...71E_Plus.gb.pdf which together with tools for removal can do the trick. This Antox71 paste is also important not to have reappearing of the rust.
regards Milos
Hello Charles and Milos,
Thanks for the great responses. I really appreciate it!
The advice from both of you regarding the "pickling" and "passification" of the stainless steel surface is also something I came across from my own research. It's good to hear about other peoples experiences and that it is possible to resolve.
The question I have now is if the products, such as Antox 71, may be used in non-food-preparation area of a federally inspected meat plant? In Canada the regulations suggest that is allowed, but i'm concerned our customer may not want to as the chemical is very corrosive and is being applied to a packaging machine... albeit which is a non-food contact surface.
This being said, the CFIA list of acceptable/allowed non-food chemicals do list several "Rust removal" products; however, I am not sure if these are the same type of chemicals as Antox 71 and the like?
Here are some examples of the rust removal products listed by the CFIA:
Hello James
Best thing that you can do is to call some welder to take a look and he will now what to do. I took a look at few chemicals you put I am not sure if they will do the job.
Let me tell you how it was in my production. We noticed small traces of rust and changed color where plates of the machine were welded(just welds were bad other was ok). When welding technician came he tested that place with magnet and since the magnet stick he told me that stainlees steel lost quality because it was not welded in correct way. So we neded to do protection with this paste that he had with him. Also this paste was really expensive and came in big package. In our case it was not wise to buy it it is better to hire good welder to fix this something problem. this paste is welders tool and not something for you to have for regular use. But again try to find good welding technician to check what is real problem. I also found this on the web http://www.damstahl....e_treatment.pdf
Thanks again Milos.
I mentioned your experience to our team, and it really helped. We're considering outsourcing finishing of our machines (as you suggested), or having our techs do the treatment in the future using Antox 71 or the like.
Also, I came across an NSF certified pickling gel in case some readers are interested. It's called Wonder Gel by Bradford Derustit -- i'm not endorsing them by any means, but having NSF certification looks good.
http://info.nsf.org/...ters/148253.pdf
http://www.derustit..../wonder_gel.php
http://www.derustit....fs/brochure.pdf
Cheers,
James
Hi all.
Rust is a problem with almost all kinds of metals. When the surface of Stainless steel is gets rubbed with that of simple steel, the protective layer of the stainless steel may get damaged. This may cause it to rust. Similarly, when you weld over a stainless steel surface you are destroying this protective layer. This also may cause it to rust some more.
According to me, welding would not be an exact solution for this problem. There is this liquid cleaner called Innosoft B570 that cleans off rust immediately in a single use. It works really well on steel, stainless steel, aluminum and chrome. Since you wanted a cleaner that can be used on surfaces that are in contact with food, I can assure you that this cleaner is harmless. It is 100% organic and does not leave behind any chemicals o the metal surface. This is a regular product that I use in my kitchen.
Hi all.
Rust is a problem with almost all kinds of metals. When the surface of Stainless steel is gets rubbed with that of simple steel, the protective layer of the stainless steel may get damaged. This may cause it to rust. Similarly, when you weld over a stainless steel surface you are destroying this protective layer. This also may cause it to rust some more.
According to me, welding would not be an exact solution for this problem. There is this liquid cleaner called Innosoft B570 that cleans off rust immediately in a single use. It works really well on steel, stainless steel, aluminum and chrome. Since you wanted a cleaner that can be used on surfaces that are in contact with food, I can assure you that this cleaner is harmless. It is 100% organic and does not leave behind any chemicals o the metal surface. This is a regular product that I use in my kitchen.
Dear TimReeves,
Thks yr info. perhaps you could inform an accessible link confirming that the chemical is officially approved for use with food-contact surfaces. Unfortunately, AFAIK, "organic" is not an automatically adequate description for manufacturing applications.
Rgds / Charles.C
PS - actually the OP was related to non-food contact surfaces but as you probably deduced, this is a relatively infrequent requirement on this forum.
Yes sure.
You can have a look at their website and go through the range of products. I personally use these products at home and found them really good and promising.
Yes sure.
You can have a look at their website and go through the range of products. I personally use these products at home and found them really good and promising.
Dear TimReeves,
Thks for response.
Yes, i did look up their website at time of yr previous post but could not see anything similar to that mentioned in my post.
However please feel free to elaborate the relevant text if you can see anything specific ?
Rgds / Charles.C
Dear TimReeves,
Thks for response.
Yes, i did look up their website at time of yr previous post but could not see anything similar to that mentioned in my post.
However please feel free to elaborate the relevant text if you can see anything specific ?
Rgds / Charles.C
You are most welsome dear...
Check the following link
Innosoft B570 as a Rust Remover
Here, the 3rd point of the"Innosoft is aggressive for rust but mild for metals" section speaks about it being food safe. They would not have mentioned it on their website is it were not safe enough. I have seen the results and it works really good.
Dear TIm Reeves,
Pls re-read my post #8. It's really quite simple.
Rgds / Charles.C
thanks, this solved my problem as well