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[TN]

cobia running. the sky was a weird blue today with a yellow/orange foreign object in the sky. it has been so long since we have seen this here.



have a safe Memorial Day


TN

[LarryB]

cobia running. the sky was a weird blue today with a yellow/orange foreign object in the sky. it has been so long since we have seen this here.



have a safe Memorial Day


TN

Hey TN, how about a shot of the rig you work on

[porthole]

Hey - our job is tough enough - but stupid people = job security.

The description is inaccurate, the failure was apparently caused by corrosion. BUT, in 1994 my town had a 36" high pressure (990 psi) fail due to a nick in the pipe caused by someone burying a stolen pickup.

The explosion (incredible) happened near an apartment complex, 6 apartment buildings (not units - buildings) burned to the ground, another 20-30 were damaged.

"had this sent to me by one of the guys in the office, and it was sent to him by a person from the utility company Northwest Energy.

You may or may not know about the law in the USA requiring you call for utility locating before you do any excavation. The pictures below are a result of a farmer using a post hole digger without calling for "locates" and he hit an underground, high-pressure cross country gas pipe.

They never did find the guy………. And the explosion took out 2 homes.
Seriously, call before you dig!"



Call before you dig

[porthole]

Something new with snopes - their pictures don't copy.

Go here

http://www.snopes.com/photos/accident/gasmain.asp#photo4

[sportygordy]

Something new with snopes - their pictures don't copy.

Go here

http://www.snopes.com/photos/accident/gasmain.asp#photo4

I WAS GONNA SAY, THAT WOULD BE ONE HELL OF A POST HOLE...

[Twolanerider]

Something new with snopes - their pictures don't copy.

Go here

http://www.snopes.com/photos/accident/gasmain.asp#photo4

Tried a couple from that article to see if they would.  Images dl'd just fine here .

[TN]

the ground must have been a bit saturated with gas to cause a hole that size. makes ya wonder about all the buried gas lines and there condition.


scary chit

TN

[porthole]

the ground must have been a bit saturated with gas to cause a hole that size.

Don't think so.

In 94 my department dealt with was a the time the largest gas pipeline rupture in a residential area in the country.

The Texas Eastern pipeline was 36" diameter, 990psi. Think about that for a minute. The pipeline went from Texas to Maine.

Around 11:55pm the pipe failed. I lived about 3 miles from was called ground zero. My house shook. We heard the chatter on the radio almost immediately, I grabbed my video camera and headed out - not knowing where I was going.

There was NO fireball.

36" of 990psi gas with a head of steam from Texas spewed for almost 90 seconds before it lit off.

To this day I am still amazed at what we saw - heard - did.

The fireball was about 500' tall. The noise was equal to what I have heard at two shuttle launches, and indeed it looked the shuttle upside down. A mile from ground zero and you had to yell in each others ear to hear.

The hole from the blast was larger then the one pictured above, and that was "just" a pressure release.

One of the first calls to Emergency Management came from Texas to one of the facilities in NJ, "hey we just had a large pressure drop around the Jamesburg area, anything going on"?
Edison received a record 50,000 plus 911 calls in the first hour.

There was so much product spewing out of the pipes the it took 4 men, turning a 4' diameter shut off wheel, 2 hours to reduce the flow 50%. About 3.5 hours into the incident the gas was shut down and we started the mop up.

When I reported work in the morning it was like nothing I had ever seen. We were bused to the site with the instructions that we would be searching for up to 250 people that were missing.

Within days everyone was accounted for and remarkably there were no injuries.

I still believe the 3 man crew on the first due engine are truly heroes (they can be seen riding in towards the fireball). The officer on the engine had an idea what they running too, he drew a line and made a defense and probably saved 90% of the complex.

Can you imagine driving a rig into the chaos? 1500 residents literally running for their lives and your trying to snake an engine through the crowd.

The crew received no recognition for their actions.

makes ya wonder about all the buried gas lines and there condition.

Yes it does.

[GasRat]

Most pipeline ruptures don't have any fire involved.  What causes the hole is the pressure of the gas blowing out of the pipe. Just like an air hose breaking.  The main difference is that your dealing with the volume, 100psi from a 3/8" hose is nothing like 990psi from a 36" line.   Gas lines are set to deliver these pressures under load, so wether it's homes using the gas or a complete rupture, the system will try to deliver the 990psi.

There has to be some kind of ignition source to light the gas off, and you would have a hard time igniting it at the pipe due to the high pressure. Natural gas also has a pretty high flashpoint (about 1200 deg) This is how we are able to weld on live gas lines without igniting the gas. That's usually why it will blow for a while to build up gas and ignite further away.  Once ignited, you have to shut off the supply to put it out.

Also thought I would mention "USA" Underground Service Alert.  Here in California the # is 811. It's a free service for homeowners, you are supposed to call them before digging and they will contact all utilities to come mark there facilities. If you hit a line without notifying them you could be on the hook for all damages.

[LarryB]

back to the show

[screem]

Most pipeline ruptures don't have any fire involved.  What causes the hole is the pressure of the gas blowing out of the pipe. Just like an air hose breaking.  The main difference is that your dealing with the volume, 100psi from a 3/8" hose is nothing like 990psi from a 36" line.   Gas lines are set to deliver these pressures under load, so wether it's homes using the gas or a complete rupture, the system will try to deliver the 990psi.

There has to be some kind of ignition source to light the gas off, and you would have a hard time igniting it at the pipe due to the high pressure. Natural gas also has a pretty high flashpoint (about 1200 deg) This is how we are able to weld on live gas lines without igniting the gas. That's usually why it will blow for a while to build up gas and ignite further away.  Once ignited, you have to shut off the supply to put it out.

Also thought I would mention "USA" Underground Service Alert.  Here in California the # is 811. It's a free service for homeowners, you are supposed to call them before digging and they will contact all utilities to come mark there facilities. If you hit a line without notifying them you could be on the hook for all damages.

Gas rat is right on the money with assessment of trying to ignite natural gas under pressure, its actually hard to ignite it...100% gas burn...it has to be a mixture between 5% and 15% to burn...any or more or any less..and no ignition. I hottap 12" lines at 240 psi , been doing this work for 37 years...never a fire or rapid expansion of gases (explosion)....it is usually a secondary source of ignition on the edge of the hot zone is where the problems tend to occur...Call before you dig....its the law!!

[Screamin]

Call before you dig....its the law!!

And hope like hell the contract locater got it right.   

[porthole]

The Edison "light off" was determined to have been caused by static electricity

[screem]

And hope like hell the contract locater got it right.   

thats why my company uses only in house locaters

[Talon]

.