We use the term ‘drilling toolface’ in connection with deflection tools or steerable motors and can express it in two ways. Physically, the place on a deflection tool, usually marked with a scribe line, is positioned to a particular orientation while drilling to determine the future course of the wellbore. Conceptually, “toolface” is a shortened …
There are two essentially different types of inclination-only tools in current use. The simple MD TOTCO deviation survey tool (single shot) so, called after its manufacturer, and the slightly sophisticated Teledrift style of tool. Totco Ring A Totco ring is not really a drilling sub. We place a small insert inside the drill string between …
Halliburton’s Geopilot RSS rotary steerable system also uses “point the bit” technology. The design concept involves the deflection of a flexible shaft between the drilling bit and the drill string. A high-side reference housing contains a compact and rugged computer-controlled bias unit (eccentric rings) to impart a controlled deflection to this shaft element, allowing for …
Schlumberger provides three types of PowerDrive RSS or rotary steerable systems with different principles of operation, and different generations of tools exist within some of these groups. The division of systems is as follows: In addition to the above rotary steerable systems, a fourth service combines PowerDrive technology with an integrated motor power section. All …
The Baker Hughes AutoTrak RSS (Rotary Steerable) uses a non-rotating sleeve close to the drilling bit. The sleeve utilizes three independent hydraulic and control systems. The hydraulic pistons can push the bit to one side of the hole. And therefore, changing the wellbore’s inclination and/or direction (Figure 1). We can integrate the RSS AutoTrak with …
Jetting (or badgering) technique is used in directional wells to deviate wellbores in the soft formation. The technique was developed in the mid-1950s and superseded the use of whipstocks as the primary deflection technique. Although jetting or badgering in directional drilling has subsequently been supplanted by downhole motor deflection assemblies (as the primary deflection method), …
With the advent of steerable systems, some directional wells are planned and drilled with complex profile types involving 3-dimensional turns. Generally, this happens mainly in the case of re-drills, where old wells are sidetracked and drilled to entirely new targets. However, these complex well paths are harder to drill, and the old adage that “the …
In oil and gas wells, hole deviation is a common drilling problem caused by a number of factors. This deviation results in the wellbore not being perpendicular to the target formation. Also, this can lead to a number of issues, including reduced productivity, lost circulation, and even well blowouts. We can control hole deviation by …
The whipstock is an old directional drilling tool that is used today primarily to perform well sidetracking out of the casing. Whipstocks and jetting techniques of various types were the principal deflection tools for many years before turbine-type and positive-displacement mud motors were fully developed and made economical for drilling applications. A whipstock is a …
Geosteering is “the drilling of a horizontal or other deviated well, where decisions on well path adjustment are made based on real-time geologic and reservoir data. In conventional directional drilling, the well path is steered according to a predetermined geometric plan. The objective is to follow the line as closely as possible. Geosteering is a …