Umbilical-Less Tubing Hanger Installation Controls System

Abstract

The umbilical-less tubing hanger running installation tool, ROCS ("Remote Operated Control System") was first introduced as an R&D project to the market in early 2020. By February 2021, it is in operation for Aker BP in the North Sea on Deepsea Nordkapp. ROCS is specifically designed to increase the robustness and efficiency of running the production tubing in the well. In a traditional operation, the Tubing Hanger Running Tool ("THRT") normally communicates topside through an umbilical. The ROCS eliminate the controls umbilical by having two methods of communication to the THRT, either acoustic or through wired pipe, preference is acoustic. This also eliminates the topside WorkOver Completion System ("WOCS"). The approximately 16meter long ROCS is also designed with a Ready To Run ("R2R") principle, where the ROCS, THRT and Tubing Hanger ("TH") is made ready on land for offshore operations, already connected and tested. The system is redundant and based on a closed loop hydraulics, powered by a subsea HPU, electrically supplied from subsea batteries. The SHPU is small in size and power consumption, capable of providing the required flow at 690bar. The control functions occur through electrically held DCV's ("Directional Control Valve") for controlling all of the required TH functions. The ROCS is capable of performing 3 operations of each TH function within the allocated deployed period. The energy required is provided between the hydraulic accumulators and batteries. Pressure balanced accumulators are included to optimize all deepwater operations. A properly sized clean reservoir is installed, interfacing the pre charged accumulators. ROCS is controlled through a modular and user-friendly topside HMI ("Human Interface Machine"), communicating acoustically or through wired pipe over any type communication protocol. The benefits include removing personnel from red zone, as well as eliminating time to clamp umbilical to the drillpipe. This significantly reduces mobilization of the system to a few hours, which also eliminates the topside deck space considerably. The running time is reduced and allows to increase speed of the drill pipe. This also reduces the risk of damaging production tubing or downhole equipment. There is no risk of downtime due to damaged conduit and the operating weather window is increased.