SOME ASPECTS OF THE OPERATION OF POSITIVE DISPLACEMENT MOTORS
Molodilo, Vladimir I. – Cand.Tec.Sci., chief drilling engineer, LLC VNIIBT-Burovoy Instrument, vmolodilo@integra.ru vmolodilo@integra.ru
Korotaev, Sergey N. – deputy service director, LLC VNIIBT-Burovoy Instrument, SKorotaev@integra.ru SKorotaev@integra.ru
Dyakonov, Grigory A. – deputy chief drilling engineer, LLC VNIIBT-Burovoy Instrument, GDyakonov@integra.ru GDyakonov@integra.ru
УДК 622.24
Key words: well drilling, axial load, torque, drill bit rations, wellbore quality, control, accuracy, positive displacement motor, differential pressure, breaking out of threaded connections, emergency systems.
The paper concerns two aspects which are relevant to the efficient operation of positive displacement motors. The first aspect is self-unscrewing of threaded connections in the downhole motor assembly, and analysis of factors contributing to incidents caused by the above phenomenon.
Provided are case histories and analysis of causes of incidents, as well as recommendations for incident response and prevention, developed by LLC VNIIBT-Burovoy Instrument. The second aspect concerns the possibility to control the drilling process, including automatic control based on pressure change. It allows to obtain comprehensive data concerning the real-time bottomhole conditions, motor and bit condition, change of rock properties, etc., without complex and expensive telemetric systems, which is not possible in turbodrilling and rotary drilling.
SOME ASPECTS OF THE OPERATION OF POSITIVE DISPLACEMENT MOTORS
Molodilo, Vladimir I. – Cand.Tec.Sci., chief drilling engineer, LLC VNIIBT-Burovoy Instrument, vmolodilo@integra.ru
Korotaev, Sergey N. – deputy service director, LLC VNIIBT-Burovoy Instrument, SKorotaev@integra.ru
Dyakonov, Grigory A. – deputy chief drilling engineer, LLC VNIIBT-Burovoy Instrument, GDyakonov@integra.ru
Key words: well drilling, axial load, torque, drill bit rations, wellbore quality, control, accuracy, positive displacement motor, differential pressure, breaking out of threaded connections, emergency systems.
The paper concerns two aspects which are relevant to the efficient operation of positive displacement motors. The first aspect is self-unscrewing of threaded connections in the downhole motor assembly, and analysis of factors contributing to incidents caused by the above phenomenon. Provided are case histories and analysis of causes of incidents, as well as recommendations for incident response and prevention, developed by LLC VNIIBT-Burovoy Instrument. The second aspect concerns the possibility to control the drilling process, including automatic control based on pressure change. It allows to obtain comprehensive data concerning the real-time bottomhole conditions, motor and bit condition, change of rock properties, etc., without complex and expensive telemetric systems, which is not possible in turbodrilling and rotary drilling.
