Diverless subsea hot tap system with lateral pipe tie-in

摘要

A diverless process of tapping a pressurized subsea pipeline without removing the pipeline from service. The process includes the steps of lowering and landing a measurement tool onto the pipeline in order to check ovality and straightness of the pipeline. Pipe lift frames are lowered and landed onto the pipeline spaced from a chosen location. The pipeline is lifted by hydraulic actuators or mechanical screws on the lift frames. A hot tap machine and accompanying orientation frame are lowered from the surface and landed on the pipeline between the pipe lift frames. A fitting clamp is secured to the pipeline. A hot tap machine is lowered onto the hot tap fitting and orientation frame. The pipeline is then tapped with the hot tap machine.