摘要 |
Dual-walled piping segments and pipelines are described that use an annular bulkhead to secure the jacket pipe radially outside of the carrier pipe near the axial ends of the piping segment. Pup joints are welded to each end of the carrier pipe, and the bulkheads are welded to the pup joints. The bulkheads have a number of features that provide improved load path control for axial forces induced by temperature differentials. There is a mechanical load-sharing interlock mechanism provided between the bulkhead and the interior pup joint and field joint closure joints designed to transmit stress loading to a plurality of ridges or threads, that may be enhanced by thermal contraction, and preclude axial movement between the jacket pipe and pup joint. A number of methods are described for creating the load-sharing interlock. Additionally, the bulkhead has a generally arcuate cross-section that defines an interior channel. The arcuate cross-section allows the bulkhead to be somewhat flexible to absorb axial and radial loading while reducing the available heat transfer rate. The bulkhead also contains several ports for pressure equalization and plugged ports for the pressure-thermal-chemical conditioning of the annular spaces.
|