Rusting in Cornelius keg

[thunderbird7]

I am relatively new to home brewing, only about a year now, and have picked up loads of good advice from this forum from the early days. I'm Hoping someone can help me with a problem I've had with rusting in one of my 3 Cornelius kegs - all were bought brand new from a uk supplier.

Basically I have been brewing all grain, using kegs mainly to store and dispense my brews. I had on occasion tasted a slight metallic taste in the odd glass of beer, but put it down to the kegs being new. I recent discovered that one of the AEB had two areas or rust. One on the welded seam at the top of the keg, the other around the weld of the gas in post. I only noticed as there were metallic looking tracks coming down the side of the keg to around halfway. I have only used the keg a maximum of 4 times over the past 9 months, possibly less.

I contacted my supplier of this AEB keg and they queried what I used to clean the kegs. I have only ever used VWP and Starsan, from the same supplier...... Their response was that VWP will have been the culprit as it contains chlorine. One google later I saw that the active ingredient Troclosene is a chlorine compound. I sent photos and they sent them to AEB, who also replied that a chlorine based cleaning agent was responsible.

I contacted VWP and they say there is no way VWP could have caused the problem as it only contains 1% chlorine, plus cleaners and buffers to protect materials it is used on. My supplier has forwarded the VWP response to AEB and I await a reply.

The bottom line is that I have a keg that is useless at the moment and I don't know who to believe or how to remedy the situation.
So the question is, has anyone experienced this kind of issue with their kegs?
In the combined experience of this group is it likely that such a weak solution of Chlorine caused this kind of damage?
Finally is there any way to cure the rust problem or is the keg now completely knackered?

Thanks in anticipation!

[Haydnexport]

You can clean rust off stainless and RE-passivate them quite easily, can you get some pics up ? Fwiw I use a 5mil per liter of thin bleach in every keg now , fill keg up and leave for usually 30 mins then good rinse after I had some infections. Sometimes I forget and leave them like that for days and never had an issue with rust.

[vacant]

I contacted VWP and they say there is no way VWP could have caused the problem as it only contains 1% chlorine, plus cleaners and buffers to protect materials it is used on

And that's 1% Chlorine before you mix it with water. Sounds like an AEB keg would disintegrate if you left your swimming trunks on it after a dip in a pool.

[thunderbird7]

Might be me being thick but cant see how to upload photo's tried copy and paste - I'm a novice on forums -

[thunderbird7]

Done some research so will try this

Top of keg
http://imgur.com/lW3zdh6

On weld

http://imgur.com/xoTHLFG

Thanks for responses so far - And yes it does seem a bit far fetched at that dilution

[chris2012]

Wow the top looks really bad, hopefully they replace it for you.

[thunderbird7]

Well, I had hoped for better customer service but I'm being told its something I have done.

I'm keeping it polite at the moment as I've had good service up to now from the supplier but the immediate response has been to take it to AEB who came back with the most ridiculous comments based on the pictures alone!

"It seems corrosion from chlorine content products ( probably used for cleaning ) due to not proper rinse and clean of the tank. ( if you look at the tank’s inscription they are white, not brown/black, this means that they use a detergent with acid and don’t rinse and clean the tanks properly )
More than this, we noted that the plugs are inclined and the rubber it looks a bit detached near the oval and this could means that the tanks went over pressure. We use only European stainless steel."

I suspect they are protesting too much........

[thunderbird7]

If there's something I can do myself then I'm up for the challenge........

[Haydnexport]

i dont think thats too far gone , google how the clean rust off stainless and re-passivate. The info is in this forum somewhere id imagine if you did a search.

[vacant]

this could means that the tanks went over pressure.

If true, do we conclude the pressure relief valve is at fault?

[thunderbird7]

Thanks for taking the time to respond, its appreciated - I read somewhere about using bar keepers friend to remove then re passivate.
Also using acid - anyone had experience of this -eg what acid would be most effective?

Good observation re the pressure valve! - The response from AEB was utter tosh - nothing wrong with the keg externally - they were looking at some photo's of the keg taken from a phone and made ludicrous deductions from them

[Fil]

YUK!!, IMHO,forget acid for now, but bar keepers friend can help.. give it a good clean with BKF and as long as you can clean off all the rust with it it should if just left in the air for a few days be fine..

if not you can try using a dremil tool with s STAINLESS STEEL wire brush to clean off the corrosion and then try the bkf again..
dont use a std steel wire brush tho..

i must say the pattern of drips indicated in the photos does look like some strong acid like substance like ams or crs ?starsan? has been dripped neat over the metal. But just how you would manage to concentrate an accidental acid spill at the point of the gas in post is a complete mystery??

you may need to strip down the post and dip tube to clean it and BKF it if so take care doing back up the post to keg thread is made from thin metal and is easily threaded..

[thunderbird7]

I do use Starsan, but never ever neat, dilute approx 20 ml in 10 litres in the keg, shake it up, leave for a while and invert the keg for a while to sanitise whole keg.

I really believe the problem has been something to do with the welded areas... It's a fair point regarding the inlet post getting a concentrated solution near it and I would say nigh on impossible to accidentally apply concentrated solutions in these two areas, it's bizarre and baffling to be honest.

As previously mentioned my only other cleaning/sanitiser is VWP, which has been suggested both by my home brew supplier and by AEB as the culprit. The worst of it is that there is no warning anywhere that rusting is a possible side effect of VWP (and I'm not convinced it is) and sold and used widely in home brewing circles specifically for stainless steel

Is it possible the foaming of Starsan cause such an effect? It's the only thing I can think of that would be in those areas.......?

[Wonkydonkey]

I read this thread and then looked at your pics.

I just brought a bergland pot second hand, there was some little bits of rust on the handles, I guess the last person to own it hung it up on a rusty hook, which transferred.
The inside of the lid had bits of rust here and there but it was what I would call spider/crazed or pitting rust. It was not bad
But I gave it a good scrub with a green scourer and some oxalic acid (which is in bar keepers friend) I then used white vinigar to which it made it tarnish, doh I can't say I've got rid of it but it's only on the inside of the lid

I will ask the guy who I brought it off what he used to do with it (clean/leave wet etc)

My question to you is, when you've cleaned your keg did you mix the VWP to the correct amounts and mix it in the keg , did you rinse it out afterwards
have you left it upside down for a long time (days)

Also I was reading about stainless steel with my prob and I remember reading it is only "stainless" not stain proof

Edit pic of my lid

[thunderbird7]

I do mix in the keg but only when I've added warm water to about half way up the keg, I followed the dosage on the vwp carton, 1tsp per gallon....

I may have left for a couple of hours but not overnight, although the carton suggests this for heavily soiled equipment, the kegs never look that bad when emptied of beer, never dry hopped in them, only did secondary ferment once as an experiment so very little gunk.

Thanks for taking the time to follow up, it would be great to solve this conundrum but don't be going to too much trouble......