15 replies to this topic

[Inesa]

Dear members,

I would like to ask you:

- How often do you have corrosion problems in processing equipment?

- Did it ever happen because of too aggressive cleaner?

- Who is responsible????

- How do you choose cleaners?

I would be very thankful to get some information about all this I’ve mentioned above. Any stories about unpleasant cases concerning corrosion are very welcome.


Yours

Inesa

Edited by Inesa, 30 November 2010 - 06:57 PM.

[Charles.C]

Dear Inesa,

3 comments -

Corrosion often reflects wrong choice of material of construction for process items. Food grade stainless steel is expensive but excellent resistance to usage and most cleaners IMEX. You get what you pay for (mostly).

Choice of cleaner often comes down to available / appropriate documentation (often non-existent) and then site testing / cost IMEX. Cost is often highly sensitive to buyer knowledge.

The expense depends who is responsible for buying it. If QA > always too expensive, if Production > no problem.

Rgds / Charles.C

[Inesa]

Dear Charles,

thanks for your comments!
So does that mean that equipment everywhere is modern, stainless 316L or even duplex types and resists all chemicals?
I thought there still lots of 304 that is not so corrosion resistant. And that people are getting lost in plenty of different cleaners offered in the market, chose wrong chemicals or use them wrong that cause problems....

Why then I was trying to learn all these different types of cleaners considering corrosion in order to know what is best for "my future" equipment if anyway it will be resistant to corrosion It seems it was waste of time........

Regards
Inesa

[Inesa]

I have to change the text of first post, it's crazy long, what was I thinking

[Bo Smith]

I have to change the text of first post, it's crazy long, what was I thinking

We have some machine parts that are aluminum. Chlorine based cleaners should not be used on those as damage will occur quickly. Stainless should not be showing signs of rust.
As a side note, are you familiar with passivation?

[Inesa]

As a side note, are you familiar with passivation?

Thanks Bo Smith. Yes I'm familiar. I forgot to consider that. ..
But I don't have any idea how often it should be done, how to adjust a proper time, temperature and concentration program for the specific steel. Are precise rinsing instructions included buying chemicals? What about if steel construction includes rubber gaskets how they will be affected??
Nitric acid for passivation is very aggressive. Is it possible to use citric acid instead? I can see it's not popular..
questions in my head are multiplying like microbes

[Charles.C]

Dear Inesa,

Actually the particular variety of stainless steel depends on the application, 316 is a common general one as you mention but, for example, freezer SS belts (-40degC) have their own characteristics including cleaning compatibility.

You are right that mild steel is still found due cost and others. Some people are perfectly happy to stare at corrosion every day.

Galvanised freezing boxes are still common in the seafood industry. May last for years if not dropped / forced open too often.

And as noted, the weight of aluminium wins out for some applications so that cleaning is adjusted for it. Standard Al trays + NaCl gives some nice effects after a while.

Fake 316 SS is not so rare also IMEX. Cheap(er) and nasty.

Rgds / Charles.C

[Inesa]

Thanks Charles,

You will probably think I am way behind, but what do IMEX and IMO mean? I feel stupid to ask about something that probably everyone know

[Charles.C]

Dear Inesa,

No need to apologise, it's a frequent query.

Blame it on slang acronymns, IMO = in my opinion, IMEX = in my experience

There is a (Simon) thread somewhere on the forum which lists all the common ones used here but i hv no idea where it is - Anybody, please please ...

Rgds / Charles.C

[Charles.C]

Dear Inesa,

This reference may of some interest -

 hygienic equipment materials.pdf   235.7KB   41 downloads

BTW - the link to a forum list of commonly used abbreviations is here - http://www.ifsqn.com...dpost__p__24154

(is actually within the very first entry in the forum main page, never thought of looking there of course )

Rgds / Charles.C

[AS NUR]

Dear members,

I would like to ask you:

- How often do you have corrosion problems in processing equipment?

- Did it ever happen because of too aggressive cleaner?

- Who is responsible????

- How do you choose cleaners?

I would be very thankful to get some information about all this I’ve mentioned above. Any stories about unpleasant cases concerning corrosion are very welcome.


Yours

Inesa

dear inesa...

the other factor the material of equipment and cleane is your water taht use for clean. you have to calculate corrosiveness of your water using Langelier Saturation Index (LSI).. if your water to coorosive you can adjust and adjustment depends on your water properties..

hope make you get some idea..



rgds



AS Nur

[Inesa]

Dear AS NUR,
thank you,

I'm not sure I've heard about this index before It probably has with water hardness to do. I'll have to read more about it.

best regards
Inesa

[GMO]

When building a new site, I contacted all of the suppliers to ask their opinion on my proposed chemicals. All of them refused to give an opinion then when damage occurred, blamed the chemical.

You kinda can't win on this.

[Charles.C]

Dear GMO,

All of them refused to give an opinion

You conveniently omitted to mention the process. Manufacture nitric acid ??

Rgds / Charles.C

[GMO]

Dear GMO,



You conveniently omitted to mention the process. Manufacture nitric acid ??

Rgds / Charles.C

It was a chilled RTE site so no!

It was so frustrating because we sought guidance from the equipment supplier and the chemical manufacturer before use and then get stuck in the middle as they point fingers at each other with neither admitting blame.

[Inesa]

Dear GMO,

It's very strange that cleaner sellers didn't know if it's suitable for your equipment or not!
Equipment sellers should inform you about type of steel and its properties and suitability for production task, I think...

Was you informed about the type of metal your equipment was made of? Did you use a proper dosage of cleaner?

What did you do afterwards, did you change cleaner?

Thank you for telling your case. It's very interesting, that shows that mistakes still happening and I love mistakes I can learn from, especially when they're not mine