CR4 - The Engineer's Place for News and Discussion®

Previous in Forum: Inspection of Sulphuric Acid Tank, How Often?   Next in Forum: Injection Mould
Close

Comments Format:






Close

Subscribe to Discussion:

CR4 allows you to "subscribe" to a discussion
so that you can be notified of new comments to
the discussion via email.

Close

Rating Vote:







6 comments
Participant

Join Date: Mar 2010
Posts: 1

Pig Launcher Design

04/11/2011 1:45 AM

I am learner engineer. I am in a process of designing a pig launcher. is the any one who have done it. i need some infomartion on the design itself.

Register to Reply
Pathfinder Tags: Pig launcher design
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".
5
Power-User

Join Date: Jan 2010
Location: Mineral wells Tx
Posts: 419
Good Answers: 17
#1

Re: PIG LAUNCHER DESIGN

04/11/2011 1:51 AM

GOOGLE??????

Pig Launching & Receiving
Procedures

Pig launchers are used to launch the pig into the pipeline, and pig receivers are used to receive the pigs after they have made a successful run. The choice of these pig traps will depend on the type of pig to be run and pipeline design conditions. Provisions in the station design should include handling equipment for pigs 20" and larger. Caution should be taken for liquid spillage from the pig traps.

Typical Pig Launching Procedures

The operational sequence described below is for general information only. It is not intended, nor should it be used, to train pigging system operators. Operating procedures will vary from one pipeline company to another. The following pig launching procedures can be used as a guideline for developing operating procedures.

Since company policies vary regarding whether the pig launcher is left on stream or isolated from the pipeline after the pig is launched, the operator should verify that the trap is isolated from the pipeline and depressurized before commencing any part of the launch procedure.

  1. Make sure that the isolation valve and the kicker valve are closed.
  2. In liquid systems, open the drain valve and allow air to displace the liquid by opening the vent valve. In natural gas systems, open the vent and vent the launcher to atmospheric pressure.
  3. When the pig launcher is completely drained (0 psig), with the vent and drain valves still open, open the trap (quick opening closure) door.
  4. Install the pig with the nose firmly in contact with the reducer between the barrel and the nominal bore section of the launcher.
  5. Clean the closure seal and other sealing surfaces, lubricate if necessary, and close and secure the closure door.
  6. Close the drain valve. Slowly fill the trap by gradually opening the kicker valve and venting through the vent valve.
  7. When filling is complete, close the vent valve to allow pressure to equalize across the isolation valve.
  8. Open the isolation valve. The pig is ready for launching.
  9. Partially close the main line valve. This will increase the flow through the kicker valve and behind the pig. Continue to close the main line valve until the pig leaves the trap into the main line as indicated by the pig signaler.
  10. After the pig leaves the trap and enters the main line, fully open the main line valve. Close the isolation valve and the kicker valve.
  11. The pig launching is complete.

Typical Pig Receiving Procedures

The operational sequence described below is for general information only. It is not intended, nor should it be used, to train pigging system operators. Operating procedures will vary from one pipeline company to another. The following pig receiving procedures can be used as a guideline for developing operating procedures.

Since company policies vary regarding whether the pig receiver is left on stream or isolated from the pipeline, the operator should verify whether there is any internal pressure in the receiving trap before starting any part of the receiving procedures.

  1. Make sure the receiver is pressurized.
  2. Fully open the bypass valve.
  3. Fully open the isolation valve and partially close the main line valve.
  4. Monitor the pig signaler for pig arrival.
  5. Close the isolation valve and bypass valve.
  6. Open the drain valve and the vent valve.
  7. Check the pressure gauge on the receiver to assure the trap is depressurized (0 psi).
  8. Open the trap closure and remove the pig from the receiver.
  9. Clean the closure seal and other sealing surfaces, lubricate if necessary, and close and secure the trap (quick opening closure) door.
  10. Return the receiver to the original condition.

Standard Pig Launcher / Receiver

Register to Reply Good Answer (Score 5)
Guru
Engineering Fields - Electrical Engineering - New Member United Kingdom - Member - New Member Engineering Fields - Electromechanical Engineering - New Member

Join Date: Aug 2010
Location: Under the Major Oak
Posts: 3629
Good Answers: 143
#5
In reply to #1

Re: PIG LAUNCHER DESIGN

04/14/2011 5:33 AM

We had pigging systems where I served my time but never saw them used or understood them.

Thanks.

__________________
Pessimists are rarely disappointed.
Register to Reply
Active Contributor

Join Date: Mar 2011
Posts: 19
#6
In reply to #5

Re: PIG LAUNCHER DESIGN

04/29/2011 9:36 AM

.... and now you know rest of the story.

Register to Reply
Guru

Join Date: Oct 2008
Location: Newcastle Oz
Posts: 943
Good Answers: 148
#2

Re: PIG LAUNCHER DESIGN

04/11/2011 3:58 AM

GA from me,

I was going to suggest a trebuchet myself. But I wouldn't suggest the use of a trebuchet with a "live" pig.

__________________
There are two reasons for a man to do a thing, One that sounds good, and the real one...
Register to Reply Score 1 for Off Topic
Guru
Hobbies - DIY Welding - New Member Hobbies - Target Shooting - New Member Engineering Fields - Civil Engineering - New Member United States - Member - New Member

Join Date: May 2009
Location: Red Hook, New York (Mid-Hudson River Valley)
Posts: 3893
Good Answers: 144
#3

Re: Pig Launcher Design

04/11/2011 8:32 AM

IF pigs only had wings..........

Soo sorry, I couldn't help myself!

__________________
"Veni, Vidi, Vici"; hendiatris attributed to Gaius Julius Caesar, 47 B.C.
Register to Reply Score 1 for Off Topic
Guru

Join Date: Jul 2006
Location: "Dancing over the abyss."
Posts: 4901
Good Answers: 240
#4
In reply to #3

Re: Pig Launcher Design

04/11/2011 10:48 AM

Totally off topic but had to share. I was going to chime in with the trebuchet idea.

I used the flying pig idea on my blog 2 weeks ago:

http://pmpaspeakingofprecision.com/2011/03/24/full-auto-industry-employment-not-so-fast/

Milo

__________________
People say between two opposed opinions the truth lies in the middle. Not at all! Between them lies the problem, what is unseeable,eternally active life, contemplated in repose. Goethe
Register to Reply Off Topic (Score 5)
Register to Reply 6 comments
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".
Copy to Clipboard

Users who posted comments:

CaptMoosie (1); Milo (1); Nadeem Butt (1); Tobugrynbak (1); TonyS (1); Whitephone (1)

Previous in Forum: Inspection of Sulphuric Acid Tank, How Often?   Next in Forum: Injection Mould

Advertisement