ABSTRACT:

Pipeline risers and flow lines may require intervention when the flow is restricted because of blockages from hydrates, paraffin, and other contaminates. Coiled tubing is a viable method to remove blockages in risers and pipelines by injecting chemicals or by using mechanical methods to clear the bore. Coiled tubing is limited however; by the distance the tubing can be run. Coiled tubing is currently inserted into a riser or pipeline using a topside injector head or through a hot tap subsea. Often, the pipeline is shut in, cut in half, and recovered to the surface in order to run coiled tubing. Shut in and recovery of a pipeline line is costly and time consuming. These methods of intervention grow in cost and effectiveness as the water depth increases. An improved method to maintain flow assurance and to simplify coiled tubing intervention is to install an Intervention Y fitting. These special purpose fittings can be installed in pipelines, manifolds, and topside to provide an easy access into the bore. The Intervention Y fitting provides a primary flow path that can be pigged bi-directionally and a secondary bore for the coiled tubing entry. The secondary bore provides a pressure tight inline entry point for coiled tubing so that the flow line does not need to be depressurized. The Intervention Y fitting is inexpensive and can be preinstalled at key locations along the flow path to insure the capability of coiled tubing intervention. The intervention Y fitting can be configured as a ready fitting complete with an intervention valve or as a Future Intervention Y with a zero leak path profile. In the event an intervention is needed the Future Intervention Y facilitates an easy hot tap interface and eliminates the need for a subsea installation of a hot tap fitting

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