A full-scale test program was conducted for BP America, Inc. to evaluate the performance of pipe material selected for use in high pressure, high temperature (HPHT) riser applications. Full length ultrasonic (FLUT) wall mapping was then used to select samples, and burst tests were performed at pressures exceeding 40,000 psi. The tests’ results clearly demonstrated the accuracy of the capped end burst pressures predicted by API RP 1111 as demonstrated by the low standard deviation of experimental burst pressures. The test program validated the strain-based design methodology embodied in API RP 1111, especially the empirically-based design methodology presented in Appendix B of API RP 1111.
This paper presents details on the completed program and how the industry can use the insights gained in completing this study to establish design pressures that more fully utilize material strengths for thick-wall riser pipe materials while maintaining conservative factors of safety. A performance and reliability-based design procedure based on FLUT wall mapping has been proposed and verified in this study; the use of this design procedure can improve true reliability by ensuring a better quality riser product.
Shilling, R., Alexander, C., and Livesay, R., “Limit State Design Based on Experimental Methods for High Pressure, High Temperature Riser and Pipeline Design”, Paper No. OMAE2011-49424, The 30th International Conference on Offshore Mechanics and Arctic Engineering, June 19-24, 2011, Rotterdam, The Netherlands.