Objectif Controlled directional drilling is steadily increasing. During the past few years "steerable systems" to be controlled from the surface have been developed and were successfully introduced by Eastman Christensen and others. These steerable or navigational systems allow directional or straight hole drilling without tripping the string out of the hole.With increasing depth and inclination of the borehole, the adjustment of the navigation tools becomes more difficult. Therefore, it is the aim of this project to develop an automatic system to directly adjust the navigation tool downhole. The positioning device will receive the control commands from a measuring device. A downhole closed control loop holds the preset direction at a fixed value by controlling the tool face by means of a regulating system.At the time of the project completion the majority of pieces needed for the configuration of the "Automatic Downhole Navigation Control" have been duly submitted. Among the achievements gained so far have been developed and tested in a large variety of different designs. State-of-art downhole electronics for fully directional steering ability were made available, and to a large extent have been successfully field tested. A major step forward has been made in the direction of a completely fully directional automatic systen. Among the essential areas of work within the scope of this project have been the downhole measuring and steering electronics, the closed loop steering algorithms, and the hydraulic, mechanical and electrical steering components. The "ADNC" project had considerable positive influence through the information gathered from field testing the "Vertical Drilling System" for drilling automatically straight ahead, which is a simplified version of the fully directional tool. As a next step the ADNC tool will be used for drilling the tangent section of a horizontal well, before finally a curved course in the borehole will be achieved automatically. The concept of the automatically steered downhole motor with integral bent parts has not been followed up further due to much better expectations and field results with the radial displacement steering concept.By assistance of LITERATURE AND PATENT RESEARCHES, and under consideration of the technical know-how on string components and drilling techniques as presently available, possible solutions and concepts have to be summarized and evaluated. As a result of the SYSTEM STUDY decisions will be made as to the design of the automatic tool face control.The ADJUSTING MEANS and the MEASURING AND CONTROL SYSTEM form the main two components of the downhole tool which allows to automatically control the direction of a borehole. The adjusting device may rotate in one or the other direction as long as the sensor system monitors an angle deviating from the desired value. As an alternative principle, the adjusting device may receive the deviation signal and process the required angle without continuous feedback from the transducer. The measuring system for determining the angle position of the tool consists basically of already existing electronics, which may have to be modified in a such a way that the rotary position for activating the adjusting device is measured once and transmitted to the adjusting device for further processing. This principle is value if the adjusting mechanism works on an internal closed loop basis. An another alternative, the a.m. electronics may act as a rotary angle sensor continuously measuring and comparing the actual and desired values thus forming a sensor for the control loop. Finally, the COMPLETE TOOL has to be laid out and manufactured. The combination consisting of adjusting device and measuring and control system will be lab and field tested during the second half of the project time. Field testing will be performed in connection with the SYSTEM'S SURFACE COMPONENTS which are necessary to monitor the dwnhole performance of the closed loop device. Programme(s) ENG-HYDROCARB 2C - Programme (EEC) of support for technological development in the hydrocarbons sector, 1986-1989 Thème(s) 1.2 - DRILLING Appel à propositions Data not available Régime de financement DEM - Demonstration contracts Coordinateur BAKER HUGHES INTEQ GMBH Contribution de l’UE Aucune donnée Adresse CHRISTENSENSTRAßE 1 29221 CELLE Allemagne Voir sur la carte Coût total Aucune donnée
