摘要 :
The state-of-art in the field of surface-controlled, downhole-adjustable well deviation tools is examined for both rotating and non-rotating drillstrings. This investigation is based on a literature survey and both domestic and fo...
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The state-of-art in the field of surface-controlled, downhole-adjustable well deviation tools is examined for both rotating and non-rotating drillstrings. This investigation is based on a literature survey and both domestic and foreign patent searches. Pertinent patents and devices found in the literature are reviewed for applicability, practicality, capability and possible improvements. A reasonable potential for improvement exists both for bent sub devices for non-rotating drillstrings and for expandable blade stabilizers for rotating strings. A new design is shown for one of each type of tool. Both new tools use the same trigger device and are controlled by varying drillstring circulation pressure, so use of pump-down or wireline or electric controls is avoided. The general design features of both tools appear to have avoided most problem areas reasonably well and seem to offer sufficient improvement over existing or disclosed hardware to justify development. Valid, fairly strong patents can probably be obtained on both tools. 40 figures. (ERA citation 07:045679)
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The purpose of this study is to determine the existing state of the art for small diameter, horizontal pilot hole drilling. The data were collected by contacting worldwide owners of raise or slant hole drill equipment, manufacture...
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The purpose of this study is to determine the existing state of the art for small diameter, horizontal pilot hole drilling. The data were collected by contacting worldwide owners of raise or slant hole drill equipment, manufacturers of drills and bits, and manufacturers of survey tools. The study was limited to existing equipment and completed trials. Most attempts at directional pilot hole drilling, and most survey tools are designed for near vertical, downward drilling. Several types of controllable bits are available which depend upon in-hole motors and bent or wedged assemblies to bias the direction of drilling. Accurate horizontal drilling can be achieved in this way by alternately drilling and surveying at frequent intervals. This procedure is impractical, however, from both a production and a cost standpoint. A few attempts at directional drilling have been made using ordinary drilling tools, a rotary drill string and a tricone bit. Good equipment and a well trained drill crew appeared to be the most significant factor in practical, accurate drilling, whether horizontal or vertical. Because of the cost, no one uses steerable bit drilling except for correction, and then only for short portions of an overall drill program. No satisfactory continuous readout surveying tool, coupled with a remotely controlled bit capable of direction correction, exists. An industry need exists for a high speed, directional drill bit, coupled with a continuously monitored survey tool. 2 tables. (ERA citation 10:006504)
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In answer to the mining industry's need to drill long horizontal holes in rock, a hydro-mechanical borehole guidance concept is developed and tested in the laboratory. Limiting borehole deviations to less than .020in/ft is suggest...
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In answer to the mining industry's need to drill long horizontal holes in rock, a hydro-mechanical borehole guidance concept is developed and tested in the laboratory. Limiting borehole deviations to less than .020in/ft is suggested as a possibility provided a sensor element of sufficient sensitivity is feasible. The hydro-mechanical borehole deviation sensor described here is a simple concept which uses the drilling fluid as a sensing medium. Preliminary test results using a model of this sensor indicate its straightness measurement sensitivity to be .003in/ft of penetration.
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The invention is a new device for changing the direction of advancement of a borehole being drilled for the discovery or production of oil or gas for example. The new technique involves the inducement of a side force on the bit by...
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The invention is a new device for changing the direction of advancement of a borehole being drilled for the discovery or production of oil or gas for example. The new technique involves the inducement of a side force on the bit by pumping a small quantity of formation cuttings, taken from the out-flow in the annulus, selectively to one side of the bit during part of each revolution. Drilling is accomplished by means of a conventional rock bit fitted with a cuttings discharge tube. Drilling fluid containing rock cuttings enters in the intake of a progressive cavity type pump which is powered by a contact roller which contacts the sides of the borehole during part of each revolution at or above the normal point of tangency due to gravity induced sag or bending of the drill string. The fluid containing rock cuttings is discharged selectively to one side of the bit during part of each revolution through the discharge tube. The wedging action of the cuttings between the newly cut wall and the bit cutter pushes the bit in the desired direction, acting like a mini-whipstock. Mathematical demonstrations have shown that a very small side drilling tendency (force) will produce an ample deflection of the borehole. The tool was field tested in July, 1985. It performed guite well in that it did reduce the deviation angle about one degree in 373 feet. Wear patterns observed at several points on the tool make the need for some minor modifications apparent. (ERA citation 11:012672)
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Special in-situ reservoir accessing schemes have recently been given increased consideration as a means of improving unconventional fossil fuel recovery. Specifically, the efficiency of thermal recovery methods for tar sands or ve...
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Special in-situ reservoir accessing schemes have recently been given increased consideration as a means of improving unconventional fossil fuel recovery. Specifically, the efficiency of thermal recovery methods for tar sands or very heavy oils may be significantly improved through the use of directional drilling techniques that allow additional reservoir intersection. This paper summarizes near-horizontal drilling experiences and discusses those special problems that can arise in drilling tar sands. Finally, the status of two current Sandia projects is presented. Water jet drilling of long horizontal holes from a vertical wellbore and the design of a high accuracy inertial survey system for deviated holes are each discussed. (ERA citation 05:023620)
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The objective of the research was to assess the potential for vertical, directional and horizontal air drilling in the United States and to evaluate the current technology used in air drilling. To accomplish the task, the continen...
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The objective of the research was to assess the potential for vertical, directional and horizontal air drilling in the United States and to evaluate the current technology used in air drilling. To accomplish the task, the continental United States was divided into drilling regions and provinces. The map in Appendix A shows the divisions. Air drilling data were accumulated for as many provinces as possible. The data were used to define the potential problems associated with air drilling, to determine the limitations of air drilling and to analyze the relative economics of drilling with air versus drilling mud. While gathering the drilling data, operators, drilling contractors, air drilling contractors, and service companies were contacted. Their opinion as to the advantages and limitations of air drilling were discussed. Each was specifically asked if they thought air drilling could be expanded within the continental United States and where that expansion could take place. The well data were collected and placed in a data base. Over 165 records were collected. Once in the data base, the information was analyzed to determine the economics of air drilling and to determine the limiting factors associated with air drilling.
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摘要 :
The objective of the research was to assess the potential for vertical, directional and horizontal air drilling in the United States and to evaluate the current technology used in air drilling. To accomplish the task, the continen...
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The objective of the research was to assess the potential for vertical, directional and horizontal air drilling in the United States and to evaluate the current technology used in air drilling. To accomplish the task, the continental United States was divided into drilling regions and provinces. The map in Appendix A shows the divisions. Air drilling data were accumulated for as many provinces as possible. The data were used to define the potential problems associated with air drilling, to determine the limitations of air drilling and to analyze the relative economics of drilling with air versus drilling mud. While gathering the drilling data, operators, drilling contractors, air drilling contractors, and service companies were contacted. Their opinion as to the advantages and limitations of air drilling were discussed. Each was specifically asked if they thought air drilling could be expanded within the continental United States and where that expansion could take place. The well data were collected and placed in a data base. Over 165 records were collected. Once in the data base, the information was analyzed to determine the economics of air drilling and to determine the limiting factors associated with air drilling.
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摘要 :
The Drilling Technology Division of Sandia Laboratories is developing a water jet drilling system which can be used to drill holes for draining methane from coal beds or for linking coal gasification wells. Funding is supplied by ...
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The Drilling Technology Division of Sandia Laboratories is developing a water jet drilling system which can be used to drill holes for draining methane from coal beds or for linking coal gasification wells. Funding is supplied by the Morgantown Energy Technology Center. The system will be designed to drill horizontally from existing vertical boreholes for distances up to 1000 feet at seam depths of 1000 feet or less. The two areas of new technology involved are cutting a component hole in coal with high pressure water jets and passing an articulated Drill String around the sharp corner between the vertical and horizontal holes. The University of Missouri-Rolla, under contract to Sandia, is working on improvements to the Drilling Head which they developed in an earlier project. Sandia, with UM-R assistance, has designed a prototype round-the-corner mechanism. A scale model of it is being built for use in concept evaluation. Major problem areas at this point include factors limiting length of penetration, bore gage control and seam boundary detection. (ERA citation 05:000028)
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