I am desparately trying to analyze a free spanning pipeline that may be subjected to vortex induced vibrations. DNV RP F105 requires calculation of the effective mass. This requires knowledge of the "assumed mode shape satisfying the boundary conditions". We are working out of a temporary...
I have a situation where I need to electrically isolate a segment of stainless steel pipe (A312-TN304L) from a segment of low alloy carbon steel pipe (API 5L). Does anyone have any good experience using isolation joints subsea? If so, please reply with some manufacturers. The operating...
Per API 1104 (19th edition), Appendix A, the CTOD testing should be performed at or below the lowest anticipated service temperature (LAST). The 18th edition required testing at 15 deg C below LAST. You could also look to BS 7448 for guidance.
A pipeline is installed in 3300 ft water depths (1467 psi external pressure) in a void state, i.e. internal pressure is zero. The pipeline is unburied - laying on bottom and there is a riser to the surface on one end.
The following have been proposed:
1. Pressure expansion (end cap, Bourdon...
The pipe is seamless any may possibly be reeled. As I can tell, there is no good reason the client had specified a minimum carbon level of 0.07%. Thanks for the info on the girth weld HAZ, that may lead to an interesting discussion.
A pipe mill is proposing a minimum level of 0.04% carbon for API 5L X65 steel. This is for subsea pipe that will be operating around (+) 40 deg. F, subjected to near 0.25% strain levels during installation. Anyone have an opinion on if this is too low? The client specification stated a...