Abstract
Saudi Aramco operates one of the largest offshore oilfield developments in the world. This field is made up of 41 kilometers of causeway, 3 kilometers of bridges, 27 drilling islands, 13 offshore platforms, and 16 onshore drill sites. The magnitude of the field has pushed cutting edge technology and processes to the forefront of the industry. This new development has driven achievements in multilateral and extended reach directional wells. One challenge the operator faces is to maintain proper hole cleaning in extended 8½ in. tangent sections at a 85-87° inclinations, which are drilled in excess of 10,000 ft.
Historically, drilling very long tangent sections required the use of several tandem sweep pills, wiper trips, and reaming/back reaming to maintain hole quality and efficiently remove cuttings bed from the wellbore. The negative effects of poor hole cleaning can lead to tight intervals, increased torque and drag, and eventually stuck pipe.
In an effort to drill efficiently, utilization of a new technology to increase the cutting removal was trial tested on well A1 from an onshore location of the field. The ERD well, A1, was drilled to a total depth of 30,480 ft MD (8,650 ft TVD) into a stratigraphic environment composed of limestone, shale, and siltstone. The objective of the trial test for the tool was to improve the drilling efficiency. To obtain the best possible hole cleaning, a simulation was performed by placing the tools every three stands along the tangent section in the 8½ in. hole section.
The goal of the trial test was to achieve the following:
Enhance hole cleaning by removal of cuttings bed.
Reduce the frequency/number of tandem sweep pills.
Reduce the frequency/number of wiper trips.
Reduce torque and drag and compare it with the offset wells.
Reduce drilling cost.
A service company installed a cuttings flow-meter system at the shakers, which was used to evaluate the hole cleaning efficiency and performance of the hole cleaning tools. This paper will demonstrate the systematic methodology, which Saudi Aramco and the service company used to approach the utilization of the hole cleaning tools to achieve a clean hole in well A1.