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Presentation on Static Testing Risks 1

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I'm doing a talk next month about the Comparative Risks of Hydrostatic vs. Pneumatic testing. I know we've beaten this horse into the ground a number of times, but if anyone is interested in looking at the arguments in a coherent stream I've uploaded the narrated PowerPoint to a video. If you believe that hydrostatic tests are inherently safe and pneumatic tests are absolutely irresponsible then you are unlikely to make it through the 30 minute video. If you do make it through, I would be very interested in any comments you care to make.

[bold]David Simpson, PE[/bold]
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
 
Thanks, I find that to be a tough line to walk. On the one hand if you don't follow the text pretty closely people complain about getting lost. If you follow the slides then you are "reading to them". Over the years I've gotten more good reviews from following the text than I've gotten bad reviews for reading the text. I certainly haven't ever found a good balance but I know that I do tend to be awfully far in the "reading to them" side of the line.

[bold]David Simpson, PE[/bold]
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
 
The biggest issue with most chart reading presenters that I've watched is that they wind up facing the chart, rather than the audience, unless they've got their own display, in which case, they're head-down. The loss of connection with the audience might be a detriment.

My personal view is that this sometimes results in the appearance of unfamiliarity with the material. I tend to like having the charts as the basic reference, which I can read much faster myself, and have the presenter be more ad hoc, and add nuances and highlights to the text.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
I don't disagree, talking to screen or talking to your lapel both result in a total disconnection with the audience. On the other hand, I was at a talk last week and the speaker didn't have any connection with his very complex slides and I spent the whole talk trying to find any relevance between his words and his slides, can't recall a single thing he said and don't remember much from the slides.

Text slides are the most abused thing in PowerPoint and I know that at this conference next month the vast majority of presenters will have an average of 90% text slides, with an average of about 600 words/slide with no animation, a 10 point font, and 85% line spacing. In that crowd it is not hard to shine, but I'm still trying to do better than slightly above average. My week-long class has something like 1100 PowerPoint slides and when any of the 11 sections approaches 50% text slides I start frantically searching for another way to make the point. Last time I did a statistical analysis on the course it was 39% text slides (albeit, nearly all of them have some meaningful graphic), I'd like to get it lower, but so far I haven't been able to figure out how to get many of the points across without hammering them with text slides.

[bold]David Simpson, PE[/bold]
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
 
I'd be tempted to edit the audio to remove the few false starts, where you start to say a word different from the word on the screen, and then say the correct word. That's the only criticism I can justify.

I come from a world where everything is short enough to demand hydro testing, so I had not thought about the differences in testing a gas pipeline, ever, at all, until I 'met' you right here.
Consider me converted.

I think the graph showing energy storage vs length for test media selection, and the flowchart for whether to hydro test or pneumatic test, or similar, should become part of everyone's standards.
Given the rate at which standards change, you probably don't have enough time left on the planet to make it happen by yourself...

So here's a challenge:

See if you can write part of a pressure test standard, in no more than say two pages of text with a couple of illustrations, not to proselytize your beliefs, but to codify them, in such a way that your text and such could simply be inserted into or added to a code.

... which basically amounts to converting the PowerPoint to equally compelling text with a much greater density and no less clarity.

<tangent>
I'm reminded of an electrical engineer's handbook published ca 1904, which in one chapter told you _everything_ about designing a proper hydroelectric dam, and in just a few paragraphs told you that the typical intake structure has a horizontal flow, limited to a few feet per second, because fish will react to, and swim away from, a lateral current, but not a vertical current, which is why hydro dams have 'trash racks', but do not need 'fish racks' to keep the fish out of the turbines.
</tangent>

That's the kind of density I'm talking about; speaking as the putative code author, outline the circumstances under which pneumatic testing is preferred, and make the 'why' clear to a proficient reader.




Mike Halloran
Pembroke Pines, FL, USA
 
MikeHalloran,
Thank you for the kind words. I haven't figured out how to edit video yet, I may look into it in my spare time.

I've submitted articles on this subject to dozens of industry publications (including the Peer Reviewed section of Oil & Gas Facilities magazine from the SPE, their reviewer said "this is not my area of expertise, but it doesn't seem right" and it was rejected. Writing it as a white paper and posting it to my web site would ensure a dozen or so downloads a decade (actually a couple of the things on my web site garner several hundred downloads a week, but still not close to a critical mass).

The graph and flow chart were both developed new for this presentation. I may craft a new paper around those two exhibits and try the peer-reviewed route again since peer-review is the touchstone of the current generation of editors. One of my peer-reviewed articles was the starting point for a new API Standard on pneumatic controllers so I am familiar with that path to a standard.

[bold]David Simpson, PE[/bold]
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
 
"their reviewer said "this is not my area of expertise, but it doesn't seem right" and it was rejected."

Yeesh. At least he was honest, but still, finding a competent reviewer was too much work? I too like the flowchart, and Mike's idea has merit.
 
On another paper I submitted to peer review I had mistyped link in one of my references. None of the reviewers found it (none of them verified references in other words), but one of them said "Figure 3 looks like it was hand drawn" (it was, but what was his point? I never learned). I have found the peer review process to be worthless in a practical sense. When I perform a peer review I follow all of the references to make sure that they actually say what was purported to be said, I load all closed-form equations into MathCad to make sure that the units work out (I don't derive them, just make sure that if the author said viscosity is in cP, that the units properly cancel and the magnitude of the answer makes sense, they too often don't). I know that no one did that since I had one empirical equation that was supposed to have the length in "miles" and my nomenclature said "feet", I caught it before publication, but the reviewers never did.

[bold]David Simpson, PE[/bold]
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
 
I like the flow chart. I would have lead with it, referred back to it regularly, and finished with it.

Before you got the flow chart, I was afraid you were going to advocate pneumatic tests in all cases, even for pressure vessels and short runs of pipe inside facilities with wastewater treatment systems. And, as you alluded to, not everyone is going to make it through your entire presentation. Heaven help the young engineer who watches all but the last 3 minutes of your presentation and sets out to pneumatic test some large vessels!

Your youtube title does state "pipeline" but the thread title and intro post here do not. Many people on this forum and in the engineering community are not pipeline-focused engineers. It would be helpful I think to emphasize early and often in the presentation that this really is intended for pipelines.

I raised an eye brow at your dismissal of the "300lb gorilla in the room" at about the 21 minute mark. I did not miss the reasoning that the failure was not part of the intended scope of the test. Still, I believe reducing the severity of the failure is prudent so long as mistake-prone humans are involved in the testing process. If the vessel had inadvertently pressured up with water would the vessel had launched itself onto the rack?

Also, the volume of water needed for a test is easier to monitor. It is more likely a crew would notice the excessive volume of water added to the system before developing any pressure than notice that an air compressor is ramping up the pressure at a slower than expected rate. Would the test crew have paused the test once they realized they had pumped in 25% too much water and wondered where the water could have gone?

 
ConstantEffort,
It is really hard to tell what the outcome would have been on that vessel if the test had been water. If you assume that the vessel started out full of some gas, then water leaking in would compress the gas and could easily have had the same outcome. If the vessel had been liquid full, then the leakage would have just split the side.

When I'm designing a test I specify soak periods to allow stresses to equilibrate. The first one is always at around twice local atmospheric pressure (3 bara or there about). This soak period is an indeterminate time, basically I say that once the pressure reaches 24 psig (or whatever), that the entire job be checked for major leaks (often takes an hour or more). If at the end of that check the pressure has declined to less than half the soak pressure then it is a failed test.

I've never had anyone pay close enough attention to how much water has been added during a hydrotest to tell if there is a major leak before the test gets fully underway. Sometimes it can be a real pain to run to ground how many trucks were unloaded, so I don't think that major leaks at low pressure are a good factor in choosing one over the other.

I copied the flow chart to earlier in the process, and the person I showed it to was underwhelmed (the rest of the presentation explains "why" for each decision box and without that background it all looks like arbitrary opinion).

[bold]David Simpson, PE[/bold]
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
 
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