Wireless Operation of Subsea Hardwares in Field X, Nigeria

Abstract

Abstract Tubing hanger (TH) installation in offshore subsea wells is a vital step in the construction and operation of oil and gas production systems. The TH is used in the completion of wells to suspend tubing from the Horizontal Xmas Tree (HXT), the wellhead (WH) or the Tubing hanger spool (THS), allow communication of hydraulic and electric down hole functions and seal-in the annulus. TH with tubing provide a conduit for the extraction of hydrocarbons from beneath the seabed. Installation and retrieval of the Tubing Hanger is typically performed using a tubular riser inside the marine riser and Blow Out Preventer (BOP). Installation and recovery of the TH is via a Tubing Hanger Running Assembly (THRA). A THRA consist of a Simplified Landing String (SLS) or also called a BOP Spanner Joint and a Tubing Hanger Running/Retrieval Tool (THRT). The control of the THRT and associated downhole functions has historically been provided through a heavy-duty umbilical or Electro-Hydraulic (EH) umbilical, manually clamped to the drill pipe during deployment. This set-up requires a large investment in associated equipment; EH Reel c/w umbilical, Work Over Control Unit (WCU), also known as Workover Control System (WOCS) and a substantial amount of rig real-estate with multiple resources to operate. Several activities and processes are required to be performed in parallel during the handling of the umbilical and clamping of the umbilical to the drill pipe during deployment. This presents specific challenges which must be carefully managed. In this context, it is essential to understand the function of an EH umbilical and the associated difficulties it brings. This paper provides an overview of the specific challenges associated with the traditional deployment of the EH umbilical and an alternative new technology which removes the EH reel and WCU from the overall set-up. It is important to clarify that at the time of writing this paper, the new technology has not been deployed in field X, Nigeria.