Pipelines

The objective was to assess and define practical methods for immediate detection of leaks and recommend existing and future state-of-the-art practical measures for inspection, detection, and monitoring to minimize leaks from seafloor pipelines. A report was prepared that reviewed domestic and foreign pipeline inspection and leak monitoring methods and proposed existing or future measures necessary to have a reliable method to detect leaks in oil and gas pipelines.

Develop improved guidelines for sizing piping and flow lines that consider the various classes of multi-phase flow, the pertinent fluid chemistry, high-flow rates, and other key variables. An analysis determined the effects of the key variables, such as mixture density, flow velocity, gas-liquid void fraction, sand concentration, fluid temperature, and concentration of corrosive materials. The results of this analysis were used to develop sets of correlations for pipe sizing recommendations. The correlations were tested for validity in large-scale flow-loop tests.

The objective was to assess the feasibility and costs associated with pipeline construction in deeper and more exposed areas of the Beaufort Sea, Alaska as contained in Lease Sale 87. This study addressed the prime concerns for construction of pipelines in the Arctic: (1) establish feasible techniques for pipeline construction in Outer Continental Shelf (OCS) Lease Sale 87, (2) identify new concepts for deep water ice covered conditions, and (3) develop cost data to be used for oil and gas development plans.

The objective was to determine the structural damage mechanism associated with wet buckles that can occur during placement and/or repair of pipelines in deepwater operations. This project included an assessment of conditions associated with buckle propagation. It also assessed the proper placement of valves during pipe laying operations to minimize a major oil spill, if the pipeline was fractured at a later date due to a wet buckle.

The objective was to assess the major components involved in offshore oil and gas pipeline corrosion. This study identified measurable items which contribute to internal corrosion problems. The project determined if the components identified in the initial stage are capable of being monitored and measured remotely with a minimum of human involvement. As the nation's offshore pipeline system grows older, the net effects of internal corrosion failure will become more acute and the need to remotely monitor internal conditions will increase.

This was a Joint Industry Project (JIP) with the U.S. Army Corps of Engineers, Waterways Experimental Station (WES) and Texas A&M University; to study parameter trends and phenomenological aspects of the moving soil sediment/pipe interaction problem. Research consisted of characterizing the viscous drag of soft soils on embedded pipelines. Equations were developed for soft soil. The soil pipeline interaction was validated with model experiments at Texas A&M University.

This is a Joint Industry Project (JIP), sponsored by Minerals Management Service and the Research and Special Programs Administration. The project will study the application of fracture mechanics techniques to problems relating to the maintenance and safety of pipelines and pressure cylinders.