TY - THES

T1 - Drilling Hydraulics Monitoring and Problem Detection

AU - Lüftenegger, Markus

N1 - embargoed until 26-09-2014

PY - 2010

Y1 - 2010

N2 - One essential element of real-time drilling monitoring is wellbore hydraulics reflected by fluid flow and pressure response. Issues such as equipment failures, kicks and wellbore instability create a significant source of drilling related problems and consequentially increase lost time and associated “red money”. In addition to lost time incidents, the optimum processes to clean and condition the hole in relation to hydraulics have a significant potential in avoiding hidden lost time. The first part of this work focuses on the analysis of prevalent problems impacting drilling hydraulics. Causes and implications, as well as the distinct patterns of real-time measurements during and prior to a particular problem are discussed. Several months of operational data and related morning reports have been studied to support the analysis and to provide example cases. A detection and verification tree (DVT) at the end of each section summarizes the main monitoring observations and suggested verification steps to diagnose selected hydraulics related drilling problems. Further, recently developed problem detection systems are reviewed. Generally these systems can be divided into three generations. They mainly dealt with the automatic detection of drillstring washouts, kicks and losses. The second part of this work outlines a concept to monitor the response of the standpipe pressure during pump start-up operations. Main objective of the concept is to avoid operational problems caused by pressure surges resulting from gelation effects and cuttings settling. Analysis of data at a high degree of operational detail generated using automated operations recognition showed that pressure surges can be minimized if the pump is started in an optimal fashion. The concept is implemented by a monitoring screen depicting the magnitude of the pressure surge in relation to the pump start-up procedure and other important parameters thus enabling the drilling personnel to act on the information generated. In this way, hidden lost time resulting from overcautious pump start up can be avoided. The third part of this work describes the conceptual development of a kick detection system based on real-time flowrate and return flowrate measurements. Main objective of the system is to provide automatic detection and verification of an imminent kick situation during drilling. The number of false alarms could be reduced by implementing flow transients encountered during pump start-up and axial pipe movement in the detection routine. Initial tests carried out on historical real-time data showed that the system is capable to detect kicks with the required sensitivity whereas the false alarm rate was in the range of 2 to 10 false alarms per day.

AB - One essential element of real-time drilling monitoring is wellbore hydraulics reflected by fluid flow and pressure response. Issues such as equipment failures, kicks and wellbore instability create a significant source of drilling related problems and consequentially increase lost time and associated “red money”. In addition to lost time incidents, the optimum processes to clean and condition the hole in relation to hydraulics have a significant potential in avoiding hidden lost time. The first part of this work focuses on the analysis of prevalent problems impacting drilling hydraulics. Causes and implications, as well as the distinct patterns of real-time measurements during and prior to a particular problem are discussed. Several months of operational data and related morning reports have been studied to support the analysis and to provide example cases. A detection and verification tree (DVT) at the end of each section summarizes the main monitoring observations and suggested verification steps to diagnose selected hydraulics related drilling problems. Further, recently developed problem detection systems are reviewed. Generally these systems can be divided into three generations. They mainly dealt with the automatic detection of drillstring washouts, kicks and losses. The second part of this work outlines a concept to monitor the response of the standpipe pressure during pump start-up operations. Main objective of the concept is to avoid operational problems caused by pressure surges resulting from gelation effects and cuttings settling. Analysis of data at a high degree of operational detail generated using automated operations recognition showed that pressure surges can be minimized if the pump is started in an optimal fashion. The concept is implemented by a monitoring screen depicting the magnitude of the pressure surge in relation to the pump start-up procedure and other important parameters thus enabling the drilling personnel to act on the information generated. In this way, hidden lost time resulting from overcautious pump start up can be avoided. The third part of this work describes the conceptual development of a kick detection system based on real-time flowrate and return flowrate measurements. Main objective of the system is to provide automatic detection and verification of an imminent kick situation during drilling. The number of false alarms could be reduced by implementing flow transients encountered during pump start-up and axial pipe movement in the detection routine. Initial tests carried out on historical real-time data showed that the system is capable to detect kicks with the required sensitivity whereas the false alarm rate was in the range of 2 to 10 false alarms per day.

KW - Drilling Hydraulics Monitoring

KW - Drilling Problem Detection

KW - Transient Hydraulics

KW - Pump Start-up

KW - Kick Detection

KW - Überwachung

KW - Durchfluss

KW - Pumpendruck

KW - Pumpen hochfahren

KW - Problemerkennung

KW - Zufluss

M3 - Master's Thesis

ER -