A set of innovative systems to minimize risks in deepwater drilling was developed. This portfolio of technologies includes quick intervention systems to be applied in case of deepwater blowouts. Between these systems, the Killing Guidance System has been developed to minimize re-insertion time of the drilling string in a blowout well, even in case of impaired visibility and therefore minimizing hydrocarbons losses, environmental impact, operational costs and exposure to liability claims. Such a system is intended to be promptly available on site for immediate intervention in case a vertical killing intervention has been decided. It is provided in a single ISO container, ready for installation and lowering from the drilling vessel rotary table. Main additional components required for Killing Guidance System functionalities are two working class ROVs and they can be easily procured in case they are not available on board. Dedicated technologies have been developed enabling the system feasibility, now worldwide patented:
in particular an innovative control system (CRC - Combined ROV Control) has been made available to ROV operator, in order to allow a single operator to manoeuvre with the standard ROV console and ROV joystick a complex and rigid system composed of the killing string, the killing guidance system and two working class ROV as a single vehicle;
Sensing System technology to support full instrumental localization of the blow-out source and therefore to perform a complete autonomous control of the string position even in case of impaired visibility.
The Killing Guidance System allows to position the killing string over the blowout source and to keep it in such a position during the beginning of the string insertion. Killing Guidance System, once started the string insertion, can be disconnected from the killing string.
The main electro-hydraulic functions of the Killing Guidance System have been tested in water, verifying with an Operator all aspects relevant to handling and intervention procedure on board. This paper focuses on test results and lessons learnt, providing a description of all the Handling and Intervention Procedures of the Killing System for operations on board of a drilling vessel, with the definition of all interfaces and relevant control SW and main functions enabling a reliable intervention on the well. Preparation of the system for final qualification on board is also addressed.
