Downhole Visualization Software Brings Sandface Completions Into Real-Time Age
Authors: Wilson Adam 
Published: February 2015

This article, written by Editorial Manager Adam Wilson, contains highlights of paper OTC 23626, ’Sandface Completions Enter the Real-Time Age With One-ofa- Kind Downhole Visualization Tool,’ by Tommy Grigsby, SPE, Ricki Jannise, SPE, Raymond Rubio, and Darrin Towers, Halliburton, prepared for the 2012 Offshore Technology Conference, Houston, 20 April-3 May. The paper has not been peer reviewed.

The operation of downhole sandface tools has relied upon depth measurements, downhole indicators that use applied tension or compression noted on a surface weight indicator, and hydraulic pressure to verify service-tool positions in relation to the sandface assembly. The introduction of multiple-zone one-trip sandface completion systems led to the development of a visualization tool that provides the tool operator with additional information to validate conventional tool-locating methods. The Real-Time Visualization Service (RTVS) package provides detailed visualization of the sandface assembly, including the service string, providing another tool-location validation method and a prejob planning tool. The visualization software provides the capability to monitor operations at the rigsite or remotely from a real-time-monitoring site or home personal computer.

Development Drivers

A number of factors have converged to drive the development of real-time downhole visualization capability. First, well depths and well deviations are increasing. The Lower Tertiary play in the Gulf of Mexico has potential well depths to 33,000 ft, while other areas in the deepwater golden triangle use horizontal sandface completions with increasing horizontal lengths. Second, sandface completions have become increasingly complex as interval lengths have increased and interval segmentation is required to stimulate the reservoir effectively. Third, the higher rig rates for deep water have highlighted the need to reduce work-string trips and time by using tools that are multifunctional, adding further complexity.

The RTVS system will use data from hookload, block movement, annulus pressure, and tubing pressure, along with a sophisticated algorithm that compensates for temperature and pipe ballooning. The program includes a visualization package that depicts the entire bottomhole sandface assembly, which is composed of the packer and screen assembly with the service tool string installed inside. Once at depth, the packer is set, anchoring the sandface assembly. The service string is then released, and the tool positions are determined for squeeze, circulating, and reverse positions for each interval to be treated.

Completion-Planning Process

The completion planning for the RTVS service is a stepped process, similar to what is being done today with the exception of more detail in each planning step. The planning process has three phases: prejob planning, real-time monitoring, and post-job analysis.

Prejob Planning. Once the well completion is defined, a step-by-step completion procedure is created. A detailed completion schematic will normally accompany the completion procedure and is provided by the service provider. The completion schematic will list the specific completion equipment for the procedure and provides the proposed component depth, length, outside diameter, and inside diameter.