Abstract
This paper presents the development and application of an integrated computational tool to assist the drilling engineer regarding prevention and detection of a kick and its circulation out of the well when operating in deepwater and ultra deepwater drilling scenarios. This tool, called UNIKICK, provides the drilling personnel with information and several computational resources covering many aspects related to well control in those drilling scenarios.
The most important features provided by the system are as follows: (a) link to databases containing regulations, standards and operational procedures to be accessed from the rig site; (b) a module to display well control information and calculations such as kick tolerance, swabbing pressure, tripping and riser safety margin; (c) a killsheet which is calculated and displayed, automatically; and (d) an interface to show graphically the expected pressure behavior at selected points inside the well and fluids production during the kick removal process.
Through the interface, the user enters the data necessary to the calculation of the killsheet and to the simulation of the pressure behavior inside the wellbore and the flow rates of the fluids from the well, using a built-in kick simulator. This simulator was developed specifically for the system and accounts for the two-phase nature of the mixture of gas and drilling fluid and for the peculiarities of an ultra deepwater well/rig equipment configuration. The interface also displays the output data generated by the simulator in a graphical format together with animation capability for the gas that is circulated out the well.
To illustrate the usage of the system, the paper presents the results for three horizontal well control cases ranging from 1000 to 3000 meters of water depth.
The paper also suggests that the system can also be used as a very powerful instructional tool for training purposes.
