Electrode,
Thank you for your comments
Some codes allow the Engineer (Owners Representative) to overrule the code requirements but these are generally structural codes.
The scary thing is API 1104 puts a lot of onus on the "Company" to make decisions.
But based on DBKs posts above the US Federal regulations clearly overrule the API code and impose a much stricter regime so cracks and arc burns are not allowed.
The US pipeline system has a shocking safety record - at least 2 accidents per month average (from leaks to explosions) from 2000 to 2012
http://en.wikipedia.org/wiki/List_of_pipeline_accidents - they clearly state this list is incomplete due to this is only reported incidents.
Obviously, no company will report something unless it was witnessed by a member of the public.
"And there has not been a documented failure of a pipeline which has been repaired with sleeves. The failures one sees in the news in the US have been related to either unrepaired mechanical damage, unrepaired corrosion, or pre 70 ERW pipe."This quote above was by DBK - 10 minutes on google and I have 5 "reported" sleeve failures including a couple below
US Department of Transportation 400 Seventh Street, SW.
Research and Special Programs Administration Washington, DC 20590
PIPELINE SAFETY ALERT NOTICE
Alert Notice: ALN-87-01 Date: 03/13/87
To: All Natural Gas Pipeline Transmission Operators & all Hazardous Liquid Pipeline Owners
Background:
On October 7, 1986, there was a pipeline failure which released thousands of barrels of gasoline from a pipeline near King of Prussia, PA. The failure occurred in a 14" API 5LX-52 seamless pipe manufactured in 1956.
A crack developed in the carrier pipe in the Heat Affected Zone (HAZ) where a full encirclement repair sleeve had been fillet welded to the pipe. The pipe failed less than one month after the sleeve had been installed. This failed pipeline was analyzed by Battelle Laboratories (Columbus Division).
Here is another doozy:
On November 21, 2011, one of the four parallel pipelines in the Line 100 System ruptured near Batesville, Mississippi, resulting in the release of natural gas. The escaping natural gas ignited and formed into a fireball that continued to burn for the next several hours. The local authorities evacuated approximately 20 homes. There were no reported injuries or fatalities.
This is taken from Corrective Action Order CPF No. 2-2011-1010H issued to Tennessee Gas Pipeline Company - Nov 28 2011
The original installation of Line 100-1 occurred in 1944.
o In 1946, a wrinkle bend on Line 100-1 was repaired with a field-fabricated, pressure-containing sleeve after a leak was discovered. That sleeve is placed at a low point in the line between two river weights.
o After reviewing the results of a prior inline inspection (ILI), TGP excavated, visually inspected, recoated, and reburied the sleeve in 2000.
So the leak from 1946, whatever the initial reason was still being contained by the sleeve !o In September 2011, TGP performed another ILI of Line 100-1, including the section that contains the wrinkle bend and sleeve, with a high-resolution magnetic flux leakage/deformation tool.
o TGP received the results from the September 2011 ILI inspection on the date of the rupture.
I cannot believe that I am the only one who thinks it strange that it takes 2 months to get test results and those "supposed" results arrive on the day their pipeline explodes - rather large coincidence ??? o The November 21, 2011 rupture of Line 100-1 occurred at the wrinkle bend with the pressure-containing sleeve.
In closing my rant, all I can say is unfortunately the US pipeline system is multiple accidents waiting to happen.
The pipeline companies are going to keep pumping their product through piping systems that are 30, 40, 50, 60, 70 years old until they either develop major leaks or explode.
How confident do you feel having a home next to a pipeline laid in the 1950s ?
Regards,
Shane