Showing posts with label Corrosion Control. Show all posts
Showing posts with label Corrosion Control. Show all posts

Thursday, April 29, 2010

NAPCA - Excellent Website for Pipe Coating Information


An excellent website for getting information on pipeline coatings is NAPCA (National Assocation of Pipe Coating Applicators.  The technical information on this website will not be as detailed as an NACE International or AWWA (American Water Works Association) pipeline coating specification, but it is useful none of the less.

In addition, it has an excellent listing of pipeline coating mills, pipeline coating suppliers, and contacts inside the pipeline coating industry.  I periodically find myself on their website getting needed information.


Wednesday, April 28, 2010

Corrosion Engineering and Twitter

I appear to be as best as I can tell one of the few persons in the Corrosion Control Industry using Twitter.  Two reasons why I have come to this conclusion is:
  • that I find only a few corrosion control companies, organizations, or individuals listed on Twitter.'
  • both SSPC and NACE International have only a few individuals following their Tweets.
I believe this may change eventually.

I have not found Plaxo to be all that useful in networking with other persons in the corrosion control industry but LinkedIn does have a small group of corrosion control professionals.  

As far as blogs on corrosion control there appears to be only a few.  Some of the corrosion control blogs are not active.  The tendency for the corrosion control blogs is to market services like DCVG surveys.

Facebook appeared to be corrosion control industry free until the Alexander reference cell invasion.  Facebook is now the number one sales website for new and experimental cathodic protection monitoring equipment. 

I have toyed with the idea that this blog would be informational and attempt to avoid controversial topics in the corrosion control industry.  However, the huge Alexander reference cell marketing  program has me pondering if I should be commenting on that matter in this blog.  Not since the late "WaveForm Analyzer " marketing program which turned out to be a failure in improving pipeline integrity have I seen such a marketing program to sell something new and improved for cathodic protection monitoring.   

The WaveForm Analyzer existed in a pre-smart pig (metal loss inline inspection tool) pipeline integrity program environment.  There is now a limited market for new and improved cathodic protection equipment in the USA oil and natural gas pipeline industry in a post-smart pig world.  I tried to explain this fact to a Canadian that came across the border to the USA to market DCVG surveys, but it took a lack of interest by pipeline operators using smart pigs to make him realize market reality for DCVG surveys.

There is a limited market for DCVG surveys in a post-smart pig world on pipelines that fall under gas transmission rules per 192 that cannot be smart pigged.  This is a fact and that is the market for DCVG surveys.

I tend to get shot at for being the messenger of what is reality in the corrosion control industry.  There is nothing wrong with DCVG surveys but smart pigs not DCVG surveys are the pipeline inspection tool of choice by new 192 and 195 federal guidelines.  Reality is that the Office of Pipeline Safety in Washington D.C. now days has a major impact on what tools a pipeline operator can or cannot use in doing an acceptable pipeline integrity program per 192 and 195 federal code minimum requirements.

My Twitter user name for my Corrosion Control Tweets is @CorrosionENG.  It is short for "Corrosion Control Engineer".

Sunday, May 31, 2009

CIS & DCVG Field Crews have to be Well Trained or the Field Data is Worthless



Wikipedia also states:

In theory, a standard analogue electronic multimeter could be used to perform a DCVG survey, but in practice it would be very difficult to take accurate readings and assess the direction of the voltage gradients correctly. A digital multimeter is completely unsuitable because of the difficulty in quickly assesing the direction of the voltage gradient. Specially designed DCVG meters are available, which have bespoke voltage ranges, specially designed transient response, rugged cases and (usually) a centre-zero meter movement for ease of use. The NACE method requires the measurements to be made using a pair of copper-copper(II) sulfate electrodes rather than simple metallic probes. In addition, the Cathodic protection is switched on and off repeatedly using an electronic switch commonly referred to as an "interrupter". Thus, two voltage readings (the "on" and "off" potentials) are taken at each fault position. Counter-intuitively, it is actually the "off" potential (measured with respect to remote earth) which is regarded as more indicative of the effectiveness of the CP applied to the pipeline. Standard surveyor's kits of DCVG equipment are available, together with training courses and software to organise and interpret the survey data.

Pipelines which do not have any form of CP may be surveyed by using a temporary DC supply and anode bed. Long pipelines frequently have more than one DC supply for their CP, requiring a number of synchronised interrupters to perform a survey. DCVG surveys are often combined with other techniques, such as CIPS and soil resistivity as part of a comprehensive corrosion protection program.

Performing a DCVG survey is relatively simple - students or recent graduates are frequently employed to collect the data. Interpreting the results is a little more complicated and this task is usually performed by a specially trained corrosion engineer.

DCVG surveys may be performed by pipeline companies themselves or, more usually, by independent specialists.

If one is doing the sloppy DCVG, then one doesn't need to have trained person collecting the field DCVG data. However, any Corrosion or Cathodic Protection Specialist knows that if the field data is sloppy then even the most experienced and well trained corrosion expert in an air conditioned office cannot make bad field data good. My guess is that the person that wrote this article maybe connected to Cath-Tech which is an Canadian manufacturer of I believe to be sloppy DCVG equipment. In CIS (close interval pipe to soil potential survey also referenced as CIPS) as well as DCVG the pipeline operator gets what is paid for. If the pipeline operator paids for sloppy CIS and DCVG, then the pipeline operator gets sloppy field data that is difficult to analyze and use to make sound pipeline integrity decisions. I have been asked in the past to analyze hundreds of miles of sloppy CIS data. I was doing nothing else during the analyze of the sloppy CIS data than making educated guesses as to what the field crew did wrong when they collected what was worthless data that couldn't be used to make any sound pipeline integrity decisions.

In order for the field data to be usable, the field personnel have to be well trained and experienced as any pipeline operator knows and NACE International does make it clear that one cannot take some college kid with no training and put him in the field and get any valid CIS and DCVG data that can be used to make sound engineering decisions on pipeline integrity.

The best CIS and DCVG field data comes from experienced personnel who are extremely highly trained in how to do CIS and DCVG field data collection. This remark in Wikipedia is not only not true but silly.