What is the ramification of removing 3 Layer Polyethylene on pipeline under water (offshore) to accommodate AUT inspection? Is it a common practice? Must the coating be removed to perform AUT inspection?
ASME B31.8 TABLE 841.1.18-1 has temperature derating factor for temperatures ranging from 250F to 450F with 50F increment.
GENERAL NOTE below the table says : For intermediate temperatures, interpolate for derating factor.
I noticed a graph of Temperature vs derating factor make a straight...
A pipeline has lost approx 50% of all thickness. Original wall thickness was 0.625-inch. Barlow's or B31G gives MAOP much lower than desired MAOP. [Desire MAOP 5,000 psi, computed MAOP based upon Barlow's 3200 psi].
Company hired a high flying engineering consulting company with top brain to...
Client does not want to coat welded joints (12-inch width) , but wishes to add extra anode weight and/or reduce spacing based upon higher coating breakdown factor. Is it acceptable practice. I like to know your thoughts.
Which coating breakdown factor should be followed? DNV or ISO?
Can anyone please state your experience to derate MAOP of a corroded pipeline using ASME 31G? Is the result obtained by using B31G reliable? Any good or bad experience? What is the difference bwteen B31G, B31G modified, and RSTRNG method? Any advantage o using one method over the other one? How...
Can anyone please state your experience to derate MAOP of a corroded pipeline using ASME 31G? Is the result obtained by using B31G reliable? Any good or bad experience? What is the difference bwteen B31G, B31G modified, and RSTRNG method? Any advantage o using one method over the other one...
What should be minimum specific gravity of a subsea pipeline so it won't float in water? I know it has to be higher than 1, but is there any recommended number by API, ASME, DNV, or by any Standard Specification? Any reference will be greatly appreciated.
When a pipe is corroded or dented, frequently a clamp (PLIDCO clamp appears to be popular) is placed around pin hole leak or pipe Thermo warp is placed around the damaged section. Is there any guideline for what should be the minimum wall thickness (after corrosion pr dent) which is considered...
i have a company wishing to perform Pipeline Inline Inspection (ILI) utilizing Mechanical Feeler Defect Sensing (MFDS) to replace hydrotest requirement. Is inline inspection to detect defects as good as hydrotest?
A 100 foot long pipe is going to be installed at a water depth of 8000 feet. External hydrostatic pressure is 3550 psi. Pipeline MAOP is 5,000 psi and hence hydrotest pressure is 6,250 psi. Pipeline is going to be hydrotested onshore prior to installation.
1. Some of us think pipeline should be...
Pipeline is sitting at 10,000 feet water depth (approx. 4444 psi hydrostatic pressure). Pipeline needs to be hydrotested subsea. By that means, the testing equipment, pressure gauge, etc will be all located subsea at a water depath of 10000 feet. MAOP of the pipeline is 8000 psi, so the...
