摘要:
An apparatus and method for damping vibration, especially torsional vibration due to stick-slip, in a drill string, Sensors measure the instantaneous angular velocity of the drill string at one or more locations along the length of the drill string. One or more vibration damping modules are also spaced along the length of the drill string. When torsional vibration above a threshold is detected, the damping module imposes a reverse torque on the drill that dampens the torsional vibration. The reverse torque can be created by imparting a frictional resistance to the rotation of the drill string. The frictional resistance can be created externally, by extending friction pads from the damping module so that they contact the bore hole wall and drag along the bore hole as the drill string rotates, or internally by anchoring a housing mounted on the drill string to the wall of the bore hole and then imposing frictional resistance on a fluid, such as a magnetorheological fluid, flowing within the drill string.
摘要:
The present invention relates to a method of treating neuropathic pain via intrathecal administration of agonists of A2A adenosine receptors (ARs).
摘要:
A method of micro-fracturing in a well bore to define the stress field and fracture system for the purpose of optimizing subsequent hydraulic fracturing well completion operations. During or subsequent to drilling of the well bore, a down hole imager takes measurements that allow the operator to select appropriate zones of the well bore for optional micro-fracture testing. The micro-fracturing testing is conducted by stopping the flow of drilling mud and expanding one, or preferably two packers incorporated into a micro-fracture module of the drill string. The pressure in the isolated zone between the packers (or below the packer if one packer is used) is pressurized until fracture occurs. The trend in the pressure in the isolated zone of the bore hole is measured during the test to assess information about the fracturing of the bore hole. After micro-fracture testing, or upon completion of the drilling, the same zone of the bore hole is again scanned by the imager and the natural beak-outs or pre- and post-micro-fracture testing images are analyzed to ascertain further information about the formation. Micro-fracture testing is repeated over different zones of the well bore as the drilling proceeds or subsequent to the drilling operation and the information from these tests is used to optimize the major fracturing in the completion phase of the drilling.
摘要:
Methods of potentiating opioid-induced analgesia in a subject by administration of a phosphodiesterase (PDE) inhibitor or glial attenuator are described. In particular, the present invention is directed to methods of treating or preventing acute or subchronic pain by administration of a PDE inhibitor or glial attenuator, such as ibudilast (3-isobutyryl-2-isopropylpyrazolo[1,5-a]pyridine), in combination with an opioid.
摘要:
Various embodiments of the present invention are directed to systems and methods for enabling software applications running on separate devices to exchange data via multiple data communication methods. In various embodiments, a data communication system is provided comprising multiple data communication devices running one or more software applications and communication manager middleware. In various embodiments, the data communication system permits the software applications to exchange data without knowledge of the actual method and/or protocol used to exchange a given set of data, and intelligently manage the exchange of data between software applications by, among other things, transmitting sets of data using a preferred communication method selected based on one or more message attributes or communication method attributes.
摘要:
A method for determining a depth of a wellbore is disclosed. The method includes determining change in a suspended weight of a drill string from a first time to a second time. A change in axial position of the upper portion of the drill string between the first time and the second time is determined. An expected amount of drill string compression related to the change in suspended weight is corrected for movement of a lower portion of the drill string between the first time and the second time. A position of the lower portion of the drill string is calculated from the change in axial position and the corrected amount of drill string compression. In one embodiment, the correcting includes estimating drill bit movement by determining an axial motion of the drill string at the earth's surface between two times having a same suspended weight of the drill string.
摘要:
A method is disclosed for determining movement mode in a drill string. The method includes measuring lateral acceleration of the drill string, determining lateral position of the drill string from the acceleration measurements, and determining mode from the position with respect to time. Also disclosed is a method including measuring drill string acceleration along at least one direction, spectrally analyzing the acceleration, and determining existence of a particular mode from the spectral analysis. Also disclosed is a method for determining destructive torque on a BHA including measuring angular acceleration at at least one location along the BHA, and comparing the acceleration to a selected threshold. The threshold relates to a moment of inertia of components of the BHA and a maximum torque applicable to threaded connections between BHA components. A warning is generated when acceleration exceeds the threshold.
摘要:
An apparatus for determining the weight on a drill bit and axial forces along a drill string drilling though an earthen formation. The apparatus comprising an LVDT incorporated into a torsional bearing of a magneto-rheological damping system such that the LVDT senses the relative displacement and accelerations between a bearing mandrel portion and a bearing casing portion of the torsional damper. The LVDT is calibrated with respect to a spring in the damping system that resists relative motion between the bearing mandrel and bearing casing such that the output of the LVDT can be transformed into the force associated with the weight on the drill bit, and the same LVDT accelerations combined with the mass distribution along the drill string to determine axial stresses.
摘要:
A method for determining a depth of a wellbore is disclosed. The method includes determining change in a suspended weight of a drill string from a first time to a second time. A change in axial position of the upper portion of the drill string between the first time and the second time is determined. An expected amount of drill string compression related to the change in suspended weight is corrected for movement of a lower portion of the drill string between the first time and the second time. A position of the lower portion of the drill string is calculated from the change in axial position and the corrected amount of drill string compression. In one embodiment, the correcting includes estimating drill bit movement by determining an axial motion of the drill string at the earth's surface between two times having a same suspended weight of the drill string.
摘要:
A method is disclosed for identifying potential drilling hazards in a wellbore, including measuring a drilling parameter, correlating the parameter to depth in the wellbore at which selected components of a drill string pass, determining changes in the parameter each time the selected components pass selected depths in the wellbore, and generating a warning signal in response to the determined changes in the parameter. Another disclosed method includes determining times at which a drilling system is conditioning the wellbore, measuring torque, hookload and drilling fluid pressure during conditioning, and generating a warning signal if one or more of maximum value of measured torque, torque variation, maximum value of drill string acceleration, maximum value of hookload and maximum value of drilling fluid pressure exceeds a selected threshold during reaming up motion of the drilling system.