Crosslink analysis keys design of long vac-resid line

Design of a hot-oil pipeline, installed last year between two U.S. West Coast petroleum refineries, centered on maintaining line temperature in the event of a shutdown. Designed for 650/sup 0/F., the 6-in. line originates at vacuum-distillation unit and runs 1 1/2 miles to a delayed coker in the receiving facility. The line's route takes it under a major highway, through an operating oil field, and under two railroad tracks and several access roads. Before detail design, studies were made to determine the operating modes of the line, both normal and abnormal, and the system characteristics required for operating contingencies. A prime concern was that the system would continually and reliably transfer material from one facility to the other and that it could be shut down and restarted with relative ease. This article covers the following areas; Van and equipment; Quality control; Viscometer; Procedure; Planned Improvements.