corrosion breakdown factor 1

[AGcervantes]

What laboratory in US can perform the testing to determine corrosion breakdown factor of coatings?
Does anybody has a reference on this lately?

 

[SJones]

What do you mean by "corrosion breakdown factor?" Is it coating breakdown factor for a cathodic protection design?

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.

 

[AGcervantes]

hi SJones, thanks for reply
Yes, coating breakdown factor for cathodic protection. The corrosion protection coating manufacturing wants to calculate the breakdown factor for his product. Do you have any recommendation on what should be the process to obtain such factor please? Is this something a lab in US can help to assess?

 

[SJones]

"Owner should preferably specify constants a and b for calculation of coating breakdown factors based
on his own practical experience of specific coating systems in a particular environment. When Owner has not
specified any such data, the default values in Table 10-4 of Annex A shall be used."

********

There appears to be no predictive science behind coating breakdown factors which would suggest that a major research project would be required in an attempt to assign coating breakdown over the lifetime of the structure based on results of laboratory testing. Since there is no standardised way of doing this, it rather becomes a case of 'how lucky do you feel.' Consequently, the majority of designers simply go with the quoted breakdown factors in the design standards, such as ISO 15589, as the path of least resistance.

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.

 

[CoCoE]

Coating breakdown factor? What is you can do a CD test? isn't it enough to estimate the coating breakdown due to CP?

 

[SJones]

No, it isn't.


Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.

 

[godel123]

I am sorry to ask this question, but: what I do not understand is the value of the breakdown factor (in my sense) should produces a value bigger than 1 in a purpose to compensate the deterioretion of the coating by injecting more current!!!

 

[AGcervantes]

Can someone tell what is the testing protocol that the manufacturer follow to determine the coating breakdown factor of a corrosion coating?

 

[SJones]

There isn't a protocol. It's called service experience - see, for example, NACE Corrosion 2015, Paper 2015-5537.

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.

 

[AGcervantes]

Hi, I see the paper refers to coating degradation on offshore installation.
Do you have a recommendation on how to setup a test to calculate the coating breakdown factor for onshore coating applications?

I think we should coat few feet of a 8-10" OD pipe and bury it 6-8' down; circulate oil to keep constant op. temperature; install CP system and start tracking current consumption to calculate the coating deterioration. Does this plan make sense?

 

[SJones]

How long do you want to wait?

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

All answers are personal opinions only and are in no way connected with any employer.

 

[AGcervantes]

Hi,
3-5 years initial monitoring to see if there is any current consumption changes. Do you know how other coating manufacturers did to asses their ƒi and Δƒ onshore(ISO 15589-1)? Do you have any recommendation on how to accelerate the study simulating a valid real-life setup?