TY - THES

T1 - Stuck Casing and Liner Mitigation - Raising Situation Awareness based on Real Time Hook Load and Friction Coefficient Analysis

AU - Fasching, Manuel

N1 - embargoed until 04-02-2025

PY - 2020

Y1 - 2020

N2 - Running a casing/liner is a technically and economically crucial operation. The increasing complexity of trajectories, as well as larger casing/liner diameters used in the geothermal industry, has caused problems with liner running operations in the past. Dealing with a stuck casing/liner consumes time and money, lowering the overall profitability of the project. To address this challenge, applications (friction model and analysis portal) and a risk diminishing workflow have been designed to enhance decision making, whilst raising situational awareness during casing/liner running. Before running the casing/liner, basic input parameters are processed on the basis of a soft-string model. The friction model generates a broomstick diagram plotting “hook load over running depth” which represents a variable set of different open hole (OH) and cased hole (CH) friction coefficients. During the actual casing/liner running job, the recorded hook load sensor data is used to calibrate the model by iteratively adjusting the OH and CH friction coefficient. After the dominant OH friction coefficient is identified, predictions for the upcoming hook load trends can be made. In this way, small deviations in hook load development over running depth can be detected and proper actions can be taken. To date, the tool has been run on more than 10 reference wells in the Molasse Basin (Bavaria, Germany) utilizing predominantly 13 3/8”, 9 5/8” and 7” liners. The outcome is a database of different dominant friction coefficients as well as hook load patterns acquired during the liner installations. Collected and analysed data, processed in the analysis portal, manages to quantify the impact of individual framework parameters such as well trajectory, friction coefficient, mud weight on the likeliness of casing getting stuck. With the aim of an overall improvement in quality of hook load trend interpretation, individual hook load patterns have been analysed in detail. Identifying the shape of a critical hook load pattern works as an early warning system, raising awareness and diminishing the risk of stuck casing/liner for future installations.

AB - Running a casing/liner is a technically and economically crucial operation. The increasing complexity of trajectories, as well as larger casing/liner diameters used in the geothermal industry, has caused problems with liner running operations in the past. Dealing with a stuck casing/liner consumes time and money, lowering the overall profitability of the project. To address this challenge, applications (friction model and analysis portal) and a risk diminishing workflow have been designed to enhance decision making, whilst raising situational awareness during casing/liner running. Before running the casing/liner, basic input parameters are processed on the basis of a soft-string model. The friction model generates a broomstick diagram plotting “hook load over running depth” which represents a variable set of different open hole (OH) and cased hole (CH) friction coefficients. During the actual casing/liner running job, the recorded hook load sensor data is used to calibrate the model by iteratively adjusting the OH and CH friction coefficient. After the dominant OH friction coefficient is identified, predictions for the upcoming hook load trends can be made. In this way, small deviations in hook load development over running depth can be detected and proper actions can be taken. To date, the tool has been run on more than 10 reference wells in the Molasse Basin (Bavaria, Germany) utilizing predominantly 13 3/8”, 9 5/8” and 7” liners. The outcome is a database of different dominant friction coefficients as well as hook load patterns acquired during the liner installations. Collected and analysed data, processed in the analysis portal, manages to quantify the impact of individual framework parameters such as well trajectory, friction coefficient, mud weight on the likeliness of casing getting stuck. With the aim of an overall improvement in quality of hook load trend interpretation, individual hook load patterns have been analysed in detail. Identifying the shape of a critical hook load pattern works as an early warning system, raising awareness and diminishing the risk of stuck casing/liner for future installations.

KW - Risikominimierung

KW - Rohrtourinstallation

KW - Hakenlast-Analyse

KW - Reibungskoeffizient-Analyse

KW - Situationsbewusstsein

KW - Modell

KW - Bohrlochverlauf

KW - Referenzbohrungen

KW - ritische Hakenlastmuster

KW - Frühwarnsystem

KW - situation awareness

KW - geothermal wells

KW - casing

KW - liner

KW - friction coefficient

KW - hook load

KW - analysis

KW - friction model

KW - well trajectory

KW - Molasse Basin

KW - risk diminishing workflow

M3 - Master's Thesis

ER -