Selection of Hose Systems for SPM Tanker Terminals

Abstract Deepwater tanker terminals incorporating the single point mooring principle are becoming quite common in the modern offshore oil production complex, both for loading export ships at crude producing areas and L1Dloading at processing locations. Large crude oil reserves and volume production capability must be augmented by large and dependable transportation systems to allow remote oil fields to remain competitive. Super-sized export tankers demand rapid loading and unloading. At Single Point Moorings, they require large diameter hose systems to achieve maximum cargo transfer rates. Proper selection of surface and sub-surface hose types can assure dependable terminal utilization. Improper selection result in unnecessary tanker delay, drowning or starving storage capacity and decreases in production. Operational and environmental conditions must be studied and all available hose designs considered before an SPM hose system can be finalized. This paper will review these factors by following simplified calculations for a hypothetical SPM terminal. It will show how to select and combine individual hose designs into an efficient, effective and economical SPM bose system. Introduction De0pwatertanker terminals incorporating the single point mooring principle have become quite common in the modern off-shore oil production complex, both for loading export shipsat crude terminals and offloading at processing locations. The military is also using SPM systems to offload refined products at storage areas. Large crude oil reserves and volume production capabilities must be augmented by large and dependable transportation systems to allow remote oilfield to remain competitive. The spectacular growth in, tanker size present?s new problems for cargo loading and discharging (Figures 1 & 2) Mammoth tankers of 300,000 dead weight ton class are here today. Twelve years ago, there was one tanker in use in the 100,000 dead weight ton class. Single point mooring systems have proven their ability to cut down turn-around time. Zueitina, Libya has experienced loading time reductions through the world?s first 24 hose SPM system, installed July 1968, from 50 hours to 27 hours. (Figure 3) Proper selection of surface and sub-surface hoses can assure dependable terminal utilization. Improper select ion can result in unnecessary tanker delay, starving storage capacity and lost production. Operational and environmental conditions must be studied and all available hose design s considered before, an SPM System can be finalized. SPM Hose In the common SPM concept there are actually two hose system (Figure 4). One connecting the PLEM (Pipeline End Manifold) with the manifolds under the buoy and one floating on the surface from the buoy to the tanker manifolds. The following are actors used in determining the length of these hose strings and the constructions of the various hose design to be incorporated into a system:Mean water depthDepth at low tide and high tideMaximum wave heightPosition of buoy relative to pipeline headerMaximum mooring distance of tankerMaximum tanker sizeMaximum elevation of tanker manifolds when lightMaximum distance from tanker manifolds to tanker railRated working pressure of hose required.