Wednesday, May 21, 2008

Pipeline Rodeo

Pipeline testing is part engineering, part art, part rodeo.


The idea with the engineering part is to pressurize the pipeline to some meaningful percentage of the maximum it was designed to hold and then measure the pressure over a meaningful time period to see if it holds. All pipelines leak, so it is normal to have a pressure drop over a few hours. But the pressure is not allowed to drop too much or that means there is a significant leak somewhere. Maybe in your backyard.

Of course you can pressurize the pipeline with "product" in it. Product as in oil. But then you risk making a big huge mess when the pipeline bursts. I've seen a few of those. I got called out to monitor a test and the line burst. The pipeline operating company had to spend a week cleaning up the thousands of gallons that sprayed all over. So usually we do a "hydrotest." Which means the oil is purged out of the line and replaced with water which is easier to clean up.

It would be an understatement to say that most people don't have a clue about the true nature of the network of oil and gas pipelines that snake their way through the backyards and backwoods of America. About 380,000 miles of pipelines are located in the US. Of course that makes sense when you understand that the US is the biggest energy hog country on the planet. So of course there is a psycho amount of pipelines. I can guarantee you would be surprised if you knew some of the places where these things go and you have no idea. You would probably be pissed if you found out that most of our pipeline infrastructure is really old and falling apart.

Pipelines sneak all over the US. Let me give you an example. There is a pipeline that carries jet fuel from the Los Angeles refinery all the way down to Miramar in San Diego where the Top Gun jet fighter school used to be located. About 20 years ago there was a huge construction project  to expand the freeways at the choke point they called the "Orange Crush" in Orange County between LA and Diego. The pipeline route just happened to cross the freeway right there in the middle of the project. The 8 inch diameter pipeline crossed the freeway interchange and if I remember right it was bolted to the side of a freeway overpass that had been dismantled. But for some crazy reason the engineers had failed to figure out that they should construct an alternate line during the construction. So, for several months the naked pipeline was left in place and it stretched straight across 10 or 12 lanes of traffic without hardly any support. I was driving to a pipeline test one day with one of the engineers and he was laughing and shaking his head and when I asked him to let me in on the joke he pointed up to the pipeline and explained that there was still jet fuel in it that day. I was shocked. It looked like an accident just waiting to happen. What if something happened on the freeway down below to impact the line? What about an earthquake? The earthquakes never stop in California, they are continuous every day. How big an earthquake would it take to bust open the line and spray jet fuel down on the public below? It was crazy. But somehow, nothing happened.

Compare that to what happened one day when we were testing "Line 1." The pipeline that goes up and down California from the LA Refinery. We cranked up the pressure to 3000 PSI. I think it was mostly 14 inch line. It's hard to remember the diameters after testing so many lines over the years. When it blew during the middle of the test, the line was snaking through a residential neighborhood and there was a car parked right on top of the line that was buried a few feet below the surface. The force of the pipeline bursting flipped the poor little car up into the air and it landed upside down in a pool of oil. Somehow the whole mess didn't catch on fire. But an exciting spectacle nevertheless.

Therein lies the rodeo nature of a pipeline test. It starts with something similar to the fans gathering at the county fairgrounds as all the work trucks filled with all those persons participating in the pipeline test show up at the test site. You have long periods of calm. Sort of like in between bull rides. And all of a sudden all hell will break loose when the bull breaks out of the pen and tears around on a rampage. The pressure drops in the pipeline and you get a sick feeling knowing that even though you can't see it, there might be a giant problem somewhere along the line. It doesn't seem like much when the pressure drops and the little piston on the pressure scale quietly drops. But those of us monitoring the test understand how much it means. It might mean a fire. Sometimes they don't bother to use water and use oil instead.

The big ruckus main event is when the pipeline test crews drive up and down the pipeline route for a while to try to figure out where the break is located. Things can get really crazy as everybody speeds around hoping to get to the break soon enough to throw a valve and shut it off and avoid a fire or an even bigger spill. People are yelling on the radios and talking over each other and trying to read ancient pipeline route as-built maps as they drive and drink coffee and chew tobacco. Time makes the problem worse so everybody is in a huge hurry and civilians often tend to get in the way. 

See, all we know back at the measuring station is that there was a big pressure drop and the test had failed. We have no way of knowing at what point along the miles and miles of pipeline the actual failure occurred. That's why the helicopter comes in handy for some tests where it is difficult to drive along the entire pipeline route to looks for leaks or breaks.

The art part of a pipeline test has to do with logging the test data. Normally, we set up a pressure recording device that is the size of a small microwave oven and has a metal disk with a piece of 12 inch circular graph paper clipped on it that rotates. As time goes by, the pressure in the pipeline draws a curved line on the pressure graph. The idea is to get the line to look nice and neat in order to impress the state fire marshall who oversees and approves the test. The "artist's judgment" comes into play when wrestling with the question of whether to pump up the pipeline during the test or not. 

If the line doesn't leak much you can just pump up the line and leave it alone until the test is done. That is an easy test. Not many of them go like that. See the line is always leaking. Sometimes hardly anything. Sometimes it is hard to tell how much it is leaking. So I have to make some calcs in order to guesstimate. You compare the total volume of the line to the rate of the pressure drop over maybe 15 minutes and try to extrapolate to figure out whether the line is leaking so bad that by the time the 8 hour test is over the pressure will have dropped below the minimum acceptable for the State Fire Marshall. 

If you calculate wrong, then you might sit there for 8 hours, with a whole crew of expensive men and equipment cranking up the cost of the test and the lost down time that they can't ship oil through the line, and then have to fix the line and do it all over again. It might be better to drive to all the valve boxes one more time before the test and bang the bolts a little tighter with a sledgehammer in anticipation of the high pressures of a test. See the pressure you test the line at is usually a lot higher than the day to day pressures on the line. So even if the line has not been leaking in normal use, it might start leaking badly or burst during the test. 
And, you want to make that pen line on the paper graph look nice and neat so that if some little shithead attorney gets a hold of it in a lawsuit they can't turn it into something negligent. So pipeline testing is artful, believe it or not.

It ends up being sort of like shooting a movie. There is a whole motley crew of various "actors" necessary to successfully complete a test. But unlike a movie, everybody has a part. And at the end you have a nice product in the form of a neat little pressure graph and an accompanying report with all the calcs and signatures of the powers that be. 

On the day of the test everybody buzzes around like the grips on a movie set. It's an organized panic. 

You've got the pipeline company folks, usually some administrator types from the home office.
Real serious. Coat and tie. They are easy to tell by their brand new hard hats that never had, and never will have, any drilling mud sprayed all over them. Office boys. No callouses on the hands, get it? Never lost any fingers throwing the spinning chain. They don't usually have a friendly attitude. Pipeline tests cost money. Huge liability exists. Sometimes they even bring an attorney or two to worry about the thousand things that can go wrong and get us all in trouble.

Then you've got the engineers. Sometimes they actually show up with pocket protectors and slide rules and broken glasses taped together. Seriously. These are the guys that talk in partial differentials with a southern drawl. They bring me the "calcs" for the test including the line specs and the temperature correction curves. Pop quiz! Can you remember the equation for the volume of a cylinder? That's all a pipeline is. A long cylinder. One that stretches with pressure and temperature and wall thickness and steel type and so forth. How about Pi-r-squared times h? Just change h for height to l for length and you've got it.

Then there are the guys that work for the pipeline company. These guys are the ones who usually wear the dirty, grimy coveralls and hard hats. And chew tobacco and swear like the roughnecks that most of them used to be until the drilling business crashed and burned and put them out of roughnecking and into pipeline babysitting. We're talking colorful characters. Roughnecks are good at spinning tales and killing time during an 8 hour test. Never a shortage of bullshit around oilhands. The engineers run out of personality a lot earlier in the test.

Then you've got some outside contractors like the company that gets hired to do maintenance on the valves along the line or does regular inspections. They are sort of worthless as they float around trying to figure out the command hierarchy and whose orders they should listen to and whose they should ignore.

You see a pipeline test is a lot like a municipal construction site. Have you ever been stuck in traffic for 30 minutes while you are late for an appointment and when you finally get up to the blockage in the roadway there is a ditch with one guy down there slaving away with a shovel while 25 "supervisors" from 6 different agencies watch him work? Pipeline tests can sort of get that way.

There is almost always a contractor that brings a bunch of "vacuum trucks" to the test. These trucks are usually strategically placed along the 10 or 20 or 50 miles of pipeline that is getting pressurized and tested. The trucks standby to suck up any leaks or god forbid, a burst. They carry sacks of that neat absorbent stuff they use for hazmat spills. They face the formidable challenge of sleeping all day and night in the cab of their trucks while still keeping an ear on the radio in case they are actually needed to do something. It's good work if you can get it.

Sometimes I have seen the local fire department show up at a pipeline test. This is really tragic. These poor guys missing time from their bodybuilding and calendar photoshoots just to drive out to some industrial hole in the wall shithole with a valve box or pumping station and no hope of getting their picture taken with their shirt off. You gotta feel sorry for them. The roughnecks always get a laugh or two out of the fireboys and will make a diving run at them by asking them a stupid question with a serious face and letting the sorry fire dude try to form an opinion about something oilfield related without having a clue what he is talking about. Hazmat questions are good. Maybe even one about the fire triangle and a gas well blowout. Ever heard of Red Adair?  Why do they call it "Midnight Death?" Do you know Murphy's email address? Even the engineers and company guys are relieved when the fireboys split and go back to the dangerous world of walking around shopping malls conducting fire inspections and chatting up teenage salesgirls while the men that make the oilfield world go round are out blowing up pipelines.

But let me tell you a secret about pipeline testing. We should be glad they do it at all. When I was in Baku, in Azerbaijan, you could look around and tell that they had never done a pipeline test. Ever. Baku is a mess. An oilfield wasteland. Rusting pipelines and manifolds and valves all over. They didn't even try to clean any of it up after the big oil boom and they moved to drill a new field. Same with all the other dead oilfields I have been to. West Texas, Elk Hills, Lake Maracaibo.

When the party is over, don't expect to see the maid come to clean the penthouse suite we have all been partying in. At least in Los Estados Unidos they try, unlike in Baku. A pipeline test every few years keeps the treehuggers and enviro-nazis at bay. And we should be glad.

Peak Oil. Peak, peak oil. The changes are a comin.' Where is Bob Dylan anyway? The oil crash is plenty enough inspiration for a blues tune. It would be nice to have something to hum when we are all reduced to metal scavenging like the Iraqi looters after Operation Freedom.
 

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