By Adolfo Gonzales
Product Manager – Tubular Engineering Software Applications, Halliburton Landmark
Part of the Spotlight Series
In the absence of laboratory-tested wear factors that resemble current field conditions, the derivation of wear factors from trusted logs is a valid alternative. The data can then be used for casing wear analysis, in the pursuit of higher well integrity. This can be achieved with DecisionSpace® CasingWear™ software, which provides a mechanism to derive wear factors using ultrasonic logs.
Specialized ultrasonic logging technology delivers an accurate, high-resolution, comprehensive confirmation of the casing condition, as well as casing-to-cement bond quality. It also identifies casing thickness to aid in analysis and calculation of burst and collapse remaining strength.
The CasingWear wear factor modeling tool allows wear factor generation from logs (e.g. ultrasonic), by selecting multiple remaining wall thickness measurements and comparing them with predicted CasingWear values at different depths, and back-calculated wear factor values. These can be used to match/adjust predicted casing wear values to log measured remaining wall thickness values. Log calibrated wear factors can be used to overwrite, or insert, single or multiple wear factor intervals along the casing length.
Tables of log derived wear factors can be organized by pre-programmed criteria (depth intervals, formations, well types and drilling areas) and saved systematically in catalog tables for future reference when working on similar drilling campaigns.
DecisionSpace® CasingWear™ to Drillpipe Body Contact Wear Factor
In addition to performing casing wear volume calculations, which are based on contact forces applied along the drillpipe tool joints; CasingWear software also analyzes the drillpipe body-to-casing contact along the wellbore to determine further wear due to drillpipe body contact. And in addition to user-defined single and multiple tool joint wear factors and/or standoff device (pipe protector, hard banding) wear factors; CasingWear software applies drillpipe body wear factors along with its drillstring modeling option.
In ideal wellbore mechanical conditions, drillpipe to casing inner wall contact conditions, dogleg severity and drillpipe tensile/compressive conditions, the drillpipe body wear factor is incorporated into existing drillpipe tool joint wear factors (Multiple Drill String wear factor mode), causing an increase in overall casing wear calculations.