History Case: Integrated Approach to Sand Management and Completion Evaluation for Sand Producer in Mature Field North Sea
Authors: Ruslan M. , Korsgaard Hansen S. , Dahm H. , Szabó N. , Benson G. 
Published: September 2016

An integrated approach to manage sand production and evaluating the actual downhole well condition including the sand screen is very critical especially in North Sea mature fields. It is divided into 2 major areas; which are surface sand management and downhole evaluation. The LEAN workflow incorporates a multidisciplinary approach, lesson-learnt, best practices and the application of multiple latest logging technologies. Integrated risk assessment was performed to ensure no compromise in the service quality, health, safety and environment. An actual history case of a mature sand producer is discussed in detail to demonstrate the integrated evaluation workflow.

The well sand management incorporates the geo-mechanical model analysis and the field experience to define the optimized well operating envelope for well start up, production optimization and shut in. The well real-time surveillance and monitoring is in place for early solid production detection. Standard evaluation package is defined for all solid samples.

A downhole assessment of well integrity was undertaken to directly identify sand entry points and assess the condition of the stand-alone premium sand control screen. A combination of multi-sensor electromagnetic and multi-finger caliper technologies were selected in order to evaluate the integrity of the complete sand screen system, from base pipe to outer shroud and with full 360-degree circumferential coverage. The multi-finger caliper provides highly accurate measurements of the internal profile of the wellbore, while the electromagnetic measurement responds to variations in downhole component thickness utilizing an array of remote field eddy current sensors. The combination of these sensors, circumferentially positioned around the wellbore, allow identification of mechanical defects, orientation and, by cross-referencing the response of each sensor technology, provide supporting information to assist with the diagnosis of the mode of failure.

A multiple array production log subsequently deployed across the screens with the objective of correlating the three-phase inflow profile with any anomalies observed in the combined multi finger caliper and electromagnetic survey. Additionally, dual tubular (tubing and production casing) integrity evaluation was performed on the upper completion with the application of pulsed eddy current technology. This measurement provides quantitative thickness evaluation through multiple concentric tubulars, utilizing the principle of electromagnetic transient decay.

Included in this intervention are preventative wax removal and solid removal operations with wireline bailing tools and tractors. The operation encountered multiple operational challenges. The problems identifications, lessons learnt and solutions will be discuss respectively.

The multidisciplinary integrated evaluations of all the results enable identification of the most economical and technical viable solution for each sand producer wells and optimized for value creation. The short, medium and long-term solutions are defined accordingly.