Motor Wired Power Section as a Solution for Efficient Downhole Torque and RPM Transmission in Long Horizontal Well. Case Study, Onshore Abu Dhabi, UAE

Abstract

Abstract Drilling long horizontal wells in mature fields in UAE are common and challenging. Some of the associated challenges are; lateral length, geological complexity and rig capabilities. One of the challenges in this case is to provide high RPM and torque to the bit and not to increase the maximum make up torque for the existing drill pipes. Powered rotary steerable systems (RSS), applied within the optimum drilling environment, can improve rate of penetration (ROP), lower risks, and reduce non-productive time (NPT), which can decrease drilling costs. Using through motor telemetry technology, a wired motor with a hollow rotor and flex shaft, allows a connection between rotary steerable systems (RSS) and logging while drilling (LWD) downhole tools. A conductor passes power and communication through the motor to operate and steer the RSS. It delivers higher rev/min and torque directly to the RSS and bit. Using the motorized RSS not only has improved ROP but has also mitigated stick-slip vibration and reduced NPT. The NPT improvements have been identified in areas, such as slip-stick vibration, drill string failures, drill string torque variations and rig equipment failures. To run the Motorized RSS on the UAE oil and gas fields the early planning and risk assessment have been conducted. Experience across the worldwide Halliburton locations, both on and offshore, have been presented to show the benefits of Motorized RSS. With improved performance as a result of increased torque and bit speed, and reduction of the stick-slip vibrations, this motor-driven RSS has delivered superior performance and improved ROP in challenging medium and hard formations. At least two horizontal wells with lateral exposure more than 8400 ft was completed shoe-to-shoe with outstanding average ROP using wired power section. It helps to exceed benchmarks by bringing greater horsepower to the rock destruction process with longer runs and higher ROPs. Implementation of wired power section technology for RSS tools will reduce failure risks either for Haliburton either for Customer rig equipment and allows to extend the lateral section footage to develop targets which was unable to hit before. The technology gives opportunity to use the existing capabilities and reduces costs for purchasing the new drillpipes and maintenance of the rig itself.