NEED ADVISE CORROSION IN INHIBITOR TANK REGD

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Neilash Kumar

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Sep 29, 2015, 3:00:50 AM9/29/15
to george....@gr.bureauveritas.com, Welding Groups
Dear Sir,

Good Morning, please find the attached tank drawing
fabricated by us for our client & it is corroded fully ,
Can you please clarify,
1. Why the tank are corroded So fast?
2. Can you please advise us the method to stop /reduce the rate of corrosion by applying a top coat &  what
type of coating to be applied?

please advise me . Material is 316L tank.

Regards
P.Neilashkumar
20150909_102338.jpg
20150909_102358.jpg

george....@gr.bureauveritas.com

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Sep 29, 2015, 3:09:46 AM9/29/15
to Neilash Kumar, Welding Groups

It looks like iron contamination.
Actions to implement:

  1. Removal of rust by stainless steel compatible brushes/disks.
  2. Pickling
  3. Avoid contact with carbon steel tools, jigs etc

best regards

Dr. Georgios Dilintas

Authorized Nuclear Inspector
Authorized Inspector Supervisor

I&F REGIONAL TECHNICAL MANAGER
BUREAU VERITAS PIRAEUS - GREECE

Tel: +30 210 40 63 113 /4 /5
Fax: +30 210 40 63 118
Cell: +30 69 44 64 62 04


Inactive hide details for Neilash Kumar ---29/09/2015 09:56:39--- Dear Sir, Good Morning, please find the attached tank drawingNeilash Kumar ---29/09/2015 09:56:39--- Dear Sir, Good Morning, please find the attached tank drawing

P.Neilashkumar[attachment "20150909_102338.jpg" deleted by George H Dilintas/GRC/VERITAS] [attachment "20150909_102358.jpg" deleted by George H Dilintas/GRC/VERITAS]
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Kannayeram Gnanapandithan

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Sep 29, 2015, 3:41:40 AM9/29/15
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Do acid pickling after wet sand blasting

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Neilashkumar

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Sep 29, 2015, 3:42:15 AM9/29/15
to material...@googlegroups.com, George Dr. Nuclear
Dear Sir,

Thanks , can you please advise me type of coat or spray that need to be applied ? It is in site working condition and the medium of service is chemical . 

P.NEILASHKUMAR 
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On Sep 29, 2015, at 10:04 AM, george....@gr.bureauveritas.com wrote:

It looks like iron contamination.
Actions to implement:

  1. Removal of rust by stainless steel compatible brushes/disks.
  2. Pickling
  3. Avoid contact with carbon steel tools, jigs etc

best regards

Dr. Georgios Dilintas

Authorized Nuclear Inspector
Authorized Inspector Supervisor

I&F REGIONAL TECHNICAL MANAGER
BUREAU VERITAS PIRAEUS - GREECE

Tel: +30 210 40 63 113 /4 /5
Fax: +30 210 40 63 118
Cell: +30 69 44 64 62 04


<graycol.gif>Neilash Kumar ---29/09/2015 09:56:39--- Dear Sir, Good Morning, please find the attached tank drawing


From: Neilash Kumar <neilas...@yahoo.com>
To: George H Dilintas/GRC/VERITAS@VERITAS, Welding Groups <material...@googlegroups.com>
Date: 29/09/2015 09:56
Subject: NEED ADVISE CORROSION IN INHIBITOR TANK REGD




 Dear Sir,

Good Morning, please find the attached tank drawing
fabricated by us for our client & it is corroded fully ,
Can you please clarify,
1. Why the tank are corroded So fast?
2. Can you please advise us the method to stop /reduce the rate of corrosion by applying a top coat &  what
type of coating to be applied?

please advise me . Material is 316L tank.

Regards
P.Neilashkumar[attachment "20150909_102338.jpg" deleted by George H Dilintas/GRC/VERITAS] [attachment "20150909_102358.jpg" deleted by George H Dilintas/GRC/VERITAS]

This message contains confidential information. To know more, please click on the following link: http://disclaimer.bureauveritas.com

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elias jarjoura

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Sep 29, 2015, 4:06:42 AM9/29/15
to material...@googlegroups.com, Neilash Kumar
1 -Should try passivization after pickling 
Nitric Acid Passivation of Stainless Steels
—Chromium-Nickel Grades (300 Series)
—Grades with 17% Chromium or more (except 440 Series)
20% by vol. nitric acid at 120/140°F (49/60°C) for 30 minutes
—Straight Chromium Grades
   (12-14% Chromium)
—High Carbon-High Chromium Grads (440 Series)
—Precipitation Hardening Stainless
20% by vol. nitric acid + 3 oz. per gallon (22 g/liter) sodium dichromate at 120/140°F (49/60°C) for 30 minutes
or
50% by vol. nitric acid at 120/140F (49/60°C) for 30 min.

Passivation is a post-fabrication method of maximizing the inherent corrosion resistance of the stainless alloy .

2 -Painting option :


a)surface preparation :

Abrasive blasting can be accomplished by using clean, fine, hard non-metallic abrasive particles (e.g. alumina or silicon carbide). The abrasive medium must be iron-free to avoid contamination, which can result in rust staining on the surface prior to coating and the compressed air carrying the abrasive medium must be free of compressor oil.

b) Prior to coating, all stainless steel surfaces must be dry and free from rust, other foreign materials, oil and grease. The presence of such contaminants may lead to failure of the coating system.

c) coating application and system 

he table below gives details of paint systems suitable for coating stainless steels and, in accordance with ISO 12944 and ISO 9223, classifies them in terms of the severity of the envisaged service environment.


Exterior EnvironmentCoating System
CategoryCorrosion RiskLocation.
C3MediumRural and urban areas with low sulphur dioxide, acid, alkali and salt pollutionTwo pack epoxy or polyurethane primer suitable for stainless steel at 30-50 micron dry, FOLLOWED BY High solids polyurethane finish at 100 micron dry
C4HighUrban and industrial areas with moderate sulphur dioxide and/or coastal areas with low salinityTwo pack epoxy or polyurethane primer suitable for stainless steel at 30-50 micron dry, FOLLOWED BY High build epoxy MIO* at 100 mm dry, FOLLOWED BY Re-coatable polyurethane finish at 60 micron dry
C5IVery HighIndustrial areas with high humidity and aggressive atmospheresTwo pack epoxy or polyurethane primer suitable for stainless steel at 30-50 micron dry, FOLLOWED BY High build epoxy MIO* at 200 micron dry (one or two coats), FOLLOWED BY Re-coatable polyurethane finish at 60 micron dry
C5MVery HighCoastal and offshore areas with high salinityTwo pack epoxy or polyurethane primer suitable for stainless steel at 30-50 micron dry, FOLLOWED BY High build epoxy MIO* at 200 micron dry (one or two coats), FOLLOWED BY Re-coatable polyurethane finish at 60 micron dry

MIO = Micaeous Iron Oxide

Cleanliness is extremely important in the successful application of paint coatings to stainless steels surfaces. Paint coatings should be applied in clean, dust-free conditions to clean, dry stainless steel surfaces.

If the correct precautions are taken, the complete coating systems suggested in the table can be applied in 'on-site'.


Best Regards 

Elias 




Subject: [MW:23584] Re: NEED ADVISE CORROSION IN INHIBITOR TANK REGD
To: neilas...@yahoo.com
CC: material...@googlegroups.com
From: george....@gr.bureauveritas.com
Date: Tue, 29 Sep 2015 10:04:06 +0300

george....@gr.bureauveritas.com

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Sep 29, 2015, 4:34:05 AM9/29/15
to elias jarjoura
Correct.
Any way contact with carbon steel, copper and chlorides must be prevented

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From: elias jarjoura
Sent: Τρίτη, 29 Σεπτεμβρίου 2015 - 11:06
To: material...@googlegroups.com; Neilash Kumar
Subject: RE: [MW:23590] Re: NEED ADVISE CORROSION IN INHIBITOR TANK REGD


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Shamal Daw

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Sep 29, 2015, 7:13:17 AM9/29/15
to material...@googlegroups.com
Hi

Some more point s
You should use spray pump (spray pickling )
For quicker production 

Suggest to use cleaner prior to pickling and passivation like phosphoric acid H3 Po4 <degreasing agent>

Also avoid direct sunlight on the job when you do pickling to avoid smut formation

KR

Shyamal 



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Mattia Degli Esposti

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Sep 29, 2015, 7:40:47 AM9/29/15
to Materials & Welding, george....@gr.bureauveritas.com
I don't suggest you a coating, otherwise you can use Carbon Steel Coated. A better procedure is to clean the surface with sandblasting with a finishing step applying a degreasing solution.

I agree with other answers: probably this is due to contamination to carbon steel (maybe come from grinding powders) or pitting corrosion due to a high corrosive environment. In this last case I suggest you to change Material with Carbon Steel galvanized.

Regards

Neilashkumar

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Sep 29, 2015, 12:28:09 PM9/29/15
to george....@gr.bureauveritas.com, Welding Groups
Dear sir ,

Thanks for your answer , now I have doubt instead of pickling spray can I go directly to passivation spray followed by rinsing and cleaning. I need your advise and procedures if any?


P.NEILASHKUMAR 
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On Sep 29, 2015, at 10:04 AM, george....@gr.bureauveritas.com wrote:

george....@gr.bureauveritas.com

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Sep 29, 2015, 1:02:13 PM9/29/15
to Neilashkumar, Welding Groups
Picking would remove contaminants (iron)

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From: Neilashkumar
Sent: Τρίτη, 29 Σεπτεμβρίου 2015 - 19:14
To: George H Dilintas
Cc: Welding Groups
Subject: Re: NEED ADVISE CORROSION IN INHIBITOR TANK REGD
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pgoswami

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Sep 29, 2015, 10:29:21 PM9/29/15
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Hi Neileshkumar,

What're the surrounding operating or environmental conditions around the tank. Are there any acid fumes involved. Looks like this tank was not insulated at all??? Is that true.

Appreciate more information on the operating conditions.

 
Thanks


 
Pradip Goswami, P.Eng,IWE
Welding & Metallurgical Engineering Specialist
Hamilton, Ontario, Canada
pgos...@quickclic.net
pradip....@gmail.com
ca.linkedin.com/pub/pradip-goswami/5/985/299

Tank Corrosion.pdf

Jim Price

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Sep 30, 2015, 12:09:13 AM9/30/15
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Pickling will remove any oxides from welds but if you are finishing the welds and removing the chromium oxide then passivation would suffice as it will remove any carbon traces that remain. We use a high nitric content for passivation that is considered a light pickling. We use this on 300 series Stainless and 2101 and 2205 Duplex material.

Best Regards,

Jim Price 

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Shamal Daw

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Sep 30, 2015, 12:09:29 AM9/30/15
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Yes you can ,directly go for passivation process if there is no pitting corrosion observed . 

Regards 
Shyamal 

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Shabbir Ahmad

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Sep 30, 2015, 12:10:08 AM9/30/15
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Thanks Dr. For your dedication to the community.

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Sent: Tuesday, 29 September 2015 8:02 PM
To: Neilashkumar
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Subject: [MW:23611] Re: NEED ADVISE CORROSION IN INHIBITOR TANK REGD

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Neilashkumar

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Sep 30, 2015, 5:57:51 AM9/30/15
to pgoswami, <materials-welding@googlegroups.com>
Dear Sir,

It's is a corrosion inhibitor storage tank for subsea pipeline project , 

operating temperature is 40degree Celsius ,
Operating pressure.     Is .7KPA
Chemical is injected inside the tank , as per design data sheet there is no insulation.

Now I have planned to visit the location and provide more information in environmental condition,
Almost 5years completed and dispatched the job.


P.NEILASHKUMAR 
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<Tank Corrosion.pdf>

Alan Denney

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Sep 30, 2015, 7:46:51 AM9/30/15
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From this I understand that it is a 316L vessel which is exposed in an offshore marine environment and has a nominal operating temperature of up to 40 degrees C and after 5 years exposure is showing signs of external pitting corrosion. I believe the reason why this has occurred is straightforward; it is operating at a temperature and in an environment where pitting is inevitable. The critical pitting temperature of 31L stainless steel is about 15 degrees C in a chloride bearing environment for solution treated 316L. Although 316L is used in marine environments it performs without pitting only at moderate temperatures [and even at moderate temperatures it will show signs of corrosion in crevices] . I also suspect the steel temperature may be higher than the greatest ambient/operating temperature of 40 deg C due to solar gain, which makes the situation worse. Alongside the welds you may be suffering crevice corrosion. Iron contamination could also be a factor particularly with some of those surface lines away from welds due to contact with carbon steel materials.

 

In my view it comes down to understanding the environment in which the material is to be exposed, (marine and high temperature relative to CPT) and the limitations of 316 stainless steel. There is a lot of information on the web if you do a search. The material selection is hence wrong for the external environment, or the tank should have been painted – yes you do paint stainless steel!

 

Alan Denney

AKD Materials Consulting Ltd

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Jim Price

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Sep 30, 2015, 8:14:19 AM9/30/15
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I definitely agree with the below statement.

From corrosion testing we have performed on 316L and 2101 duplex the HAZ on these welds are very prone to pitting and crevice corrosion due to austenite and ferrite balance.

Heat input is critical.

The elevated temperatures are definitely a factor in the corrosion equation.

With the environment  carbon pickup is definitely a factor.

 

Jim Price | Welding Engineer, CWI

Direct:  320.7463439 | Fax: 417-862-5564

jimp...@polarcorp.com

cid:image001.jpg@01D0E005.E9837830

 

 

 

 

george....@gr.bureauveritas.com

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Sep 30, 2015, 11:02:15 AM9/30/15
to material...@googlegroups.com

true because of sensitization
but the image of the vessel indicates iron contamination



best regards

Dr. Georgios Dilintas

Authorized Nuclear Inspector
Authorized Inspector Supervisor

I&F REGIONAL TECHNICAL MANAGER
BUREAU VERITAS PIRAEUS - GREECE

Tel: +30 210 40 63 113 /4 /5
Fax: +30 210 40 63 118
Cell: +30 69 44 64 62 04

Neilashkumar

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Oct 2, 2015, 12:00:46 AM10/2/15
to material...@googlegroups.com
Dear All ,

Instead of Pickling and passivation Can anyone advise or suggest any epoxy type coating spray from hempell is advisable ? I need your valuable point on this subject.
Because after pickling and passivation client is asking me what guaranty it will not corrode again? Since it is a marine environment. 


P.NEILASHKUMAR 
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Alan Denney

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Oct 2, 2015, 8:08:36 AM10/2/15
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Lu, Feng

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Oct 2, 2015, 1:11:32 PM10/2/15
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Try coating with thermal sprayed aluminum.

 

Feng Lu

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pgoswami

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Oct 2, 2015, 11:45:41 PM10/2/15
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Hi Neilashkumar,
 
I would like to add a few notes in addition to the comments of Mr. Alan Denny.
 
Painting is quite uncommon for austenitic stainless steels. Following fabrication and welding, complete pickling + aestivation is more common practice. In addition depending on the surrounding environmental conditions stainless steel vessels and piping are insulated( which is another protective shield against atmospheric corrosion). Usually  C5M grade of paits are recommended for stainless steel in marine environments.
 
Often paints may contain items such as "isocyanates" which has serious health and safety issues. In these documents the texts with yellow or green highlights are recommended while the one with red  requires "CAUTION". It would be advisable ( as stated earlier by Alan) to consult the paint manufacturers. Irrespective of painting or other option full surface cleaning and surface preparation by blasting is recommended.
 
The other and safer option would be to blast clean the surface, perform in situ pickling and aestivation and then to  insulate the vessel.
 
Thanks.
 
 
Pradip Goswami, P.Eng,IWE
Welding & Metallurgical Engineering Specialist
Hamilton, Ontario, Canada
 

From: material...@googlegroups.com [mailto:material...@googlegroups.com] On Behalf Of Alan Denney
Sent: Friday, October 02, 2015 5:07 AM
To: material...@googlegroups.com
Subject: RE: [MW:23640] RE: 23626] Re: NEED ADVISE CORROSION IN INHIBITOR TANK REGD

norsok-pc-systems-6.pdf
iso-12944--C5M.pdf
Article_ Paint coating stainless steels.pdf

pgoswami

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Oct 3, 2015, 9:08:17 AM10/3/15
to material...@googlegroups.com
Hi,
 
Resending this response after correcting some "typos"
 
Thanks.
 
Pradip Goswami, P.Eng,IWE
Welding & Metallurgical Engineering Specialist
Hamilton, Ontario, Canada
 


From: material...@googlegroups.com [mailto:material...@googlegroups.com] On Behalf Of pgoswami
Sent: Friday, October 02, 2015 11:45 PM
To: material...@googlegroups.com
Subject: RE: [MW:23642] RE: 23626] Re: NEED ADVISE CORROSION IN INHIBITOR TANK REGD

Hi Neilashkumar,
 
I would like to add a few notes in addition to the comments of Mr. Alan Denny.
 
Painting is quite uncommon for austenitic stainless steels. Following fabrication and welding, complete pickling + passivation is more common practice. In addition depending on the surrounding environmental conditions stainless steel vessels and piping are   often  insulated   ( which is another protective shield against atmospheric corrosion). Usually  C5M grade of paints are recommended for stainless steel in marine environments.
 
Often paints may contain items such as "isocyanates" which has serious health and safety issues. In these  attached  documents the texts with yellow or green highlights are recommended while the one with red  requires "CAUTION". It would be advisable ( as stated earlier by Alan) to consult the paint manufacturers.  
 
 Irrespective of painting or other option full surface cleaning and surface preparation by blasting is recommended.
 
The other and safer option would be to blast clean the surface, perform in situ pickling and  passivate and then to  insulate the vessel.  Avesta( http://www.avestafinishing.com/products/pickling-spray.aspx) has good and proven products for such passivation work. You may find out more details for local vendors.
norsok-pc-systems-6.pdf
iso-12944--C5M.pdf
Article_ Paint coating stainless steels.pdf

Lassaad Mokrani

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Oct 4, 2015, 12:20:39 AM10/4/15
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Dear All
I agree with Pradip
But, please note that the applied coating should be well selected to avoid Corrosion Under Insulation (CUI) problem.
A rough verification of the process whether the preservation of Heat will/not affect

KR 

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Alan Denney

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Oct 4, 2015, 11:55:31 AM10/4/15
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You only apply insulation if you need to insulate for process reasons.

The risk of corrosion under insulation is very real and you should not confuse insulation with protecting against corrosion. If it saturates (which it can easily do so) it is both the medium causing the corrosion and mask the corrosion from view.

Pickling and passivating will deal with the current surface corrosion on 316 stainless steel and leave it looking rust free, but the pits will still be there.

In an exposed marine environment, which has already caused a significant amount of corrosion the rust staining will re-appear.

You can pickle and passivate to clean up and then apply paint coatings to prevent this happening, but they need good surface preparation and proper application, and you should get advice from the coatings companies.

The application of coatings to 316 stainless steel is a recognised way of minimising corrosion in warm marine environments.

The idea of flame-sprayed aluminium (suggested by one correspondent) is interesting but applying it in-situ seems to be to be an even more difficult challenge than the idea of applying a decent paint coating.


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Neilashkumar

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Oct 5, 2015, 12:09:29 AM10/5/15
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Dear Sirs ,

Thank you so much of all your suggestions , I am travelling now to offshore to see the real condition of this tank and need to discuss with aramco , let me come back to you after discussion in this subject.


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pgoswami

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Oct 5, 2015, 10:12:00 AM10/5/15
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Hi Neilashkumar,

 

Aramco has some of the most comprehensive standards on Corrosion Protection".Two relevant standards are cited below. The following paragraph from SAES-L-133 may provide you some guidelines as heads up.

 
 
Thanks.
 
Pradip Goswami, P.Eng,IWE
Welding & Metallurgical Engineering Specialist
Hamilton, Ontario, Canada
 

SAES-H-004, 11 October 2006,Protective Coating Selection & Application, Requirements for Offshore Structures and Facilities

SAES-L-133, 10 August 2009 Corrosion Protection Requirements for Pipelines, Piping and Process Equipment

7.2.5 Completely coat the outer metal surface of all 300-series stainless steels that may cycle into the temperature range from 104 deg F (40 deg C) up to the maximum service temperature of the available coating systems in order to protect them from pitting and stress corrosion cracking. Use thermal spray aluminum, organic coatings with zero leachable chlorides that are approved for immersion service, or foil wraps as detailed in the NACE RP0198 - 2004, Section 4, Table 1 and EFC 55. Contact the coatings RSA in CSD/ME&CCD for a list of approved coating products. Use low leachable chloride insulation in accordance with ASTM C795. Use insulation materials and weatherproofing to prevent water ingress and that do not allow the absorption of water.

 



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To: material...@googlegroups.com
Subject: Re: [MW:23659] RE: 23626] Re: NEED ADVISE CORROSION IN INHIBITOR TANK REGD

Neilashkumar

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Oct 8, 2015, 1:25:32 AM10/8/15
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image1.JPG
Dear all ,

Please see the photos attached after my visit to offshore platform , I applied only SS wire brush , it s been removed. 
Now my doubt is can I go for pickling passivation or paint methodology? Client not approving for sweep blast as it in site condition in that case my opinion is not to coat with paint .
Only we allowed to use power tools in tank for surface cleaning . Please drop your suggestion on methodology. It s gas platform during shut down we need to clean and retain their properties of SS tank. 

image2.JPG
image3.JPG


P.NEILASHKUMAR 
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Jim Price

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Oct 8, 2015, 7:53:00 AM10/8/15
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First you probably would need to check the depth of pitting to ensure integrity concerning stress flows and repair as required especially at toe of welds or violation of allowed depth.

From what I see passivation would be minimal help, pickling would be my choice.

As far as painting is concerned you would need to clean and either passivate or pickle prior to painting.

Natural formation of oxide layer requires oxygenated condition painting would not allow for this natural process.

Copy of emails for reference I have received:

Jim,

Stainless steel self-passivates in air but the Cr/Fe surface is less than the chemically passivated stainless steel and corrosion resistance is better on chemically passivated stainless steel.

 

Dear Jim,

The nitric and citric acid treatments below are extracts from ASTM A967, I would recommend you buy it and/or other standards if you are carrying out passivation treatments on a regular basis?  While natural passivation of a virgin stainless steel surface will occur immediately it can take a day or more for the passive layer to thicken and develop an optimum thickness, assuming the surface is well aerated. That is why acid passivation treatments have been designed to accelerate the process.

 From BSSA

Nitric Acid Treatments

cid:image001.png@01D093CB.413CC450

cid:image002.png@01D093CB.413CC450

cid:image003.png@01D093CB.413CC450

Citric Acid Treatments

cid:image004.png@01D093CB.413CC450

cid:image005.png@01D093CB.413CC450

 

 

 

Jim Price | Welding Engineer, CWI

Direct:  320.7463439 | Fax: 417-862-5564

jimp...@polarcorp.com

cid:image001.jpg@01D0E005.E9837830

 

 

 

 

 

Alan Denney

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Oct 8, 2015, 11:07:07 AM10/8/15
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Alan Denney

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Oct 11, 2015, 10:22:03 AM10/11/15
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pgoswami

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Oct 11, 2015, 11:34:22 AM10/11/15
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Hi Nilesh,
 
Many ideas had been provided to this problem. The response trail is as below. In addition to the suggestions provided below, I would think the reasonable path forward would be:
  • Remove the corrosion pits by grinding/power brushing( too difficult and very arduous task in an offshore platform). Try to get as good a surface finish as possible free from any corrosion nicks.
  • Pickle and passivate with the appropriate product(Table in Page 10 would be of guidance).
  • Following pickling and passivation think about application of  one  full  coat of Belzona products as per the  link provided below.
 
You may need to discuss and write up a " Grinding, Pickiling and Coating application plan" as per your client's requirements. The health and safety aspects in dealing with "HAZARDOUS CHEMICALS" must be be there in place.
 
Thanks.
 
Pradip Goswami, P.Eng,IWE
Welding & Metallurgical Engineering Specialist
Hamilton, Ontario, Canada
 
From: material...@googlegroups.com [mailto:material...@googlegroups.com] On Behalf Of Alan Denney
Sent: Saturday, October 10, 2015 6:10 PM
To: material...@googlegroups.com
Subject: RE: [MW:23696] RE: 23626] Re: NEED ADVISE CORROSION IN INHIBITOR TANK REGD

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Emilio Cerato

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Oct 11, 2015, 10:49:18 PM10/11/15
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Dear Friends.

I need weld an equipment whose base material is RA330.

Which welding process is more suitable?

Which filler metal is better?

What do you recomended for weld? preheat? heat imput?

Thanks for your help!!!

Emilio Cerato


Kannayeram Gnanapandithan

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Oct 12, 2015, 8:29:22 AM10/12/15
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use same spec

THANKS & BEST REGARDS,
KG.PANDITHAN, IWE,  AWS-CWI, CSWIP 3.1,
CONSULTANT-WELDING & QUALITY

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pgoswami

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Oct 12, 2015, 10:18:40 AM10/12/15
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Hi Emilo,

 

This alloy is often used for high temperature furnace and other environments. You have the options of using welding products of  matching or similar chemistry, such as Rolled Alloy RA-330-4 (please see the attachment) or more alloyed welding products such as Inconel 82(E-NiCr-3) or Inconel 617(see attachment).

 

Also please see the generic guidelines for the welding product manufacturers.

 

Use the following resources to your discretion.

 

This alloy is a fully austenitic alloy an have tendency to crack while welding in thick sections. Controlled heat input , typically 1.5Kj/mm max  to be on the safe side would be advisable.

 

Do you have the design conditions with you?? That’s more important to know before making the final selection.

 

Thanks.

 

 

Pradip Goswami, P.Eng,IWE

Welding & Metallurgical Engineering Specialist

Hamilton, Ontario, Canada

pgos...@quickclic.net

pradip....@gmail.com

ca.linkedin.com/pub/pradip-goswami/5/985/299

 

 

Welding: RA330 is readily welded using RA330-04 weld fillers of matching composition. RA330-04 DC lime type electrodes are available from stock in popular sizes. RA330-04 bare welding wire is available as straight lengths for GTA welding or spooled for GMA welding. For best results do not preheat, keep interpass temperature low and use reinforced bead contours. Detailed coverage of heat resistant alloy welding techniques is given in Bulletin 201.

 

INCOLOY alloy 330 is weldable by conventional processes. Shielded-metal-arc welding should be done with INCO- WELD A welding electrode; gas-shielded-arc welding with INCONEL filler metal 82. Acceptable welds have been made in relatively heavy sections with these welding products.

 

For additional strength and corrosion resistance up to 2100°F (1150°C), INCONEL filler metal 617 and INCONEL welding electrode 117 may be used.

 

 

 

 

  1. http://www.specialmetals.com/assets/documents/alloys/incoloy/incoloy-alloy-330.pdf

 

  1. http://content.rolledalloys.com/technical-resources/databooks/RA330_DB_US_EN.pdf

 

 

 

 


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Ing. Emilio Cerato

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Oct 12, 2015, 9:54:47 PM10/12/15
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Pradip,

Thank you very muchos, very useful your help!!

Emilio

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