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Vertical Pig launcher/receievr 1
- Thread starter ssoman
- Start date
Vertical pig receivers/launchers?
I've got experience on the operation of cupped, foam, intelligent pigs on horizontal pig traps. Bear with me as this might go off point to the operation of the process but i have highligthed relevant sections.
Ensure the pig trap doors are tested and close/open according to your procedures (this covers pressures, safety locks, sealing, indications by the doors etc). not too sure on the design side.
Methods used to contain the pig is just ensuring the pressure is balanced between where you are sending it from and where it will be received. Also there are signals on the risers and around the pig trap that alerts operators when the pig arrives.
From my knowledge for intelligent pig the best velocity is between 2.5m/s to 4m/s you probably need a pressure vs flowrate diagram that is applicable to your operations/conditions this will give you what pressure you can run at at the launcher and what to expect at the receiver (for instance run at 17barg at launcher might give u a constrain of 2barg flexiblity at the receiver i.e. 15barg at receiver) this is just an example!
Once the pig arrives on site
There is always a flow diversion line around the pig launcher that helps regulates the movement of the pig by sending the fluid in the pipe to another place.
Things you have to be aware of;
Pyrophorics (ignites on exposure to air) so it requires proper COSHH assessments carried out on it. Therefore i advice pig trap be flushed with sufficient water to eliminate this risk.
Other stuffs you have to be careful of is where you drain leads to? as there are strict environmental laws on what you can dispose into the normal drain.
Know what the pipeline is like, because valves, kinks and dents, bends, reducers, take off points, could result in the pig either being stuck in the pipeline, or being diverted to another stream (this is something you really dont want to happen). Usually it is good to run a guage pig in the line first to confirm if you have dents or whatever. you dont want to have intelligent or sphere pigs getting stuck!
Sometimes to retrieve a pig you might have to keep flushing in the fluid through the line until you have confirmation signals on site. But you should be able to calculate how long it will take from the agreed velocity.
Foam pigs could also shred in the pipeline and therefore might be retrieved as pieces or never retrieved!
I'm guessing operation of a vertical pig trap will be similar in some sense? I do not know, but i'd consider horizontal over vertical anyday!
With regards to design, I only can get you designs for horizontal pigs, but nothing for the vertical
Please do drop more information or knowledge you have on this subject they will all be taken in and appreciated.
David O.
Mechanical Engineer
Graduate as of: 2007
Oil, Gas & Power
I've got experience on the operation of cupped, foam, intelligent pigs on horizontal pig traps. Bear with me as this might go off point to the operation of the process but i have highligthed relevant sections.
Ensure the pig trap doors are tested and close/open according to your procedures (this covers pressures, safety locks, sealing, indications by the doors etc). not too sure on the design side.
Methods used to contain the pig is just ensuring the pressure is balanced between where you are sending it from and where it will be received. Also there are signals on the risers and around the pig trap that alerts operators when the pig arrives.
From my knowledge for intelligent pig the best velocity is between 2.5m/s to 4m/s you probably need a pressure vs flowrate diagram that is applicable to your operations/conditions this will give you what pressure you can run at at the launcher and what to expect at the receiver (for instance run at 17barg at launcher might give u a constrain of 2barg flexiblity at the receiver i.e. 15barg at receiver) this is just an example!
Once the pig arrives on site
There is always a flow diversion line around the pig launcher that helps regulates the movement of the pig by sending the fluid in the pipe to another place.
Things you have to be aware of;
Pyrophorics (ignites on exposure to air) so it requires proper COSHH assessments carried out on it. Therefore i advice pig trap be flushed with sufficient water to eliminate this risk.
Other stuffs you have to be careful of is where you drain leads to? as there are strict environmental laws on what you can dispose into the normal drain.
Know what the pipeline is like, because valves, kinks and dents, bends, reducers, take off points, could result in the pig either being stuck in the pipeline, or being diverted to another stream (this is something you really dont want to happen). Usually it is good to run a guage pig in the line first to confirm if you have dents or whatever. you dont want to have intelligent or sphere pigs getting stuck!
Sometimes to retrieve a pig you might have to keep flushing in the fluid through the line until you have confirmation signals on site. But you should be able to calculate how long it will take from the agreed velocity.
Foam pigs could also shred in the pipeline and therefore might be retrieved as pieces or never retrieved!
I'm guessing operation of a vertical pig trap will be similar in some sense? I do not know, but i'd consider horizontal over vertical anyday!
With regards to design, I only can get you designs for horizontal pigs, but nothing for the vertical
Please do drop more information or knowledge you have on this subject they will all be taken in and appreciated.
David O.
Mechanical Engineer
Graduate as of: 2007
Oil, Gas & Power
engineeringguy
Mechanical
Vertical launcher, I can see. Vertical receiver, I can see to be a total mess, especially if you're using a pig to clean your lines.
"If experience was always the only factor, how would we get to the moon?"
"If experience was always the only factor, how would we get to the moon?"
Take the engineeringguy's advice.
I've built a bunch of vertical launchers, but never a vertical receiver. You'd need some good pin timing there, then how do you get the damn pigs, or spheres out of there??? Shake the tube?
**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)
I've built a bunch of vertical launchers, but never a vertical receiver. You'd need some good pin timing there, then how do you get the damn pigs, or spheres out of there??? Shake the tube?
**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)
Or just leave the cap open when they arrive???
**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)
**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)
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1
- #8
BigInch,
I had a crew do that once. We were dewatering a 20-inch line after a hydro and the only pig I could find was a 300 lb mandrel pig. The crew thought it was coming too slow so they opened the closure. The superintendent saw what they were doing (and that the receiver was pointed at a $1 million compressor) and he jumped into a track hoe and dropped the bucket in front of the opening. The pig (with 15 psid, nearly 5,000 lbf) exited a few minutes later and hit the bucket so hard that the near track came off the ground. The pig had a 15 degree bend in the mandrel and had to be discarded. I don't know how fast that projectile was traveling, but the result was very exciting.
Maybe a vertical (down) receiver would be a "good" idea, just need to be able to deal with the mess.
David
I had a crew do that once. We were dewatering a 20-inch line after a hydro and the only pig I could find was a 300 lb mandrel pig. The crew thought it was coming too slow so they opened the closure. The superintendent saw what they were doing (and that the receiver was pointed at a $1 million compressor) and he jumped into a track hoe and dropped the bucket in front of the opening. The pig (with 15 psid, nearly 5,000 lbf) exited a few minutes later and hit the bucket so hard that the near track came off the ground. The pig had a 15 degree bend in the mandrel and had to be discarded. I don't know how fast that projectile was traveling, but the result was very exciting.
Maybe a vertical (down) receiver would be a "good" idea, just need to be able to deal with the mess.
David
I have actually seen a horizontal sphere pig fly! Generally i dont think vertical pig traps should be preferred in any way to horizontal.
Why? well if you want to use the pig as a launcher alone that means you dont have the flexibility of pigging the line both ways...
Please do drop more information or knowledge you have on this subject they will all be taken in and appreciated.
David O.
Mechanical Engineer
Graduate as of: 2007
Oil, Gas & Power
Why? well if you want to use the pig as a launcher alone that means you dont have the flexibility of pigging the line both ways...
Please do drop more information or knowledge you have on this subject they will all be taken in and appreciated.
David O.
Mechanical Engineer
Graduate as of: 2007
Oil, Gas & Power
I once asked an operator during a HAZOP that I was facilitating how they controlled their pigging speed. He said they didn't and that pigs travelled at the speed of sound. I figured that they must be doing something wrong, because that didn't make sense to me, but being only the facilitator, my job was simply to ask the questions.
I imagine that leaving the pig receiver closure open and pumping up the pressure behind the pig might fall into the "doing something wrong" category. That's how pellet guns work.
Regards,
SNORGY.
I imagine that leaving the pig receiver closure open and pumping up the pressure behind the pig might fall into the "doing something wrong" category. That's how pellet guns work.
Regards,
SNORGY.
Here is a link to an interesting variation on the subject of "Pig Launcher"
zdas, that's almost as good as seeing the Host Country officials and the Oil Co execs getting douched with first crude afterwards. Bet that taught them not to invite you to the party!
snorgy, ... and cannons!
**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)
snorgy, ... and cannons!
**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)
Let's say the speed of sound is 1,300 ft/s (depends on a lot of things, but numbers in that range are common), then the pig is moving almost 900 miles/hr. What a time saver, pig a 5 mile line in 20 seconds.
Looking at my 300 lbm pig and assume it stopped in 5 mS then the pig would have hit the 12 ton hoe with 78 million ft-lbf. I bet it would have done more damage than we observed.
Pig speeds under 10 ft/s are pretty normal.
David
Looking at my 300 lbm pig and assume it stopped in 5 mS then the pig would have hit the 12 ton hoe with 78 million ft-lbf. I bet it would have done more damage than we observed.
Pig speeds under 10 ft/s are pretty normal.
David
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