Abstract: The present invention provides systems utilizing fiber optics for monitoring downhole parameters and the operation and conditions of downhole tools. In one system fiber optics sensors are placed in the wellbore to make distributed measurements for determining the fluid parameters including temperature, pressure, fluid flow, fluid constituents and chemical properties. Optical spectrometric sensors are employed for monitoring chemical properties in the wellbore and at the surface for chemical injection systems. Fiber optic sensors are utilized to determine formation properties including resistivity and acoustic properties compensated for temperature effects. Fiber optic sensors are used to monitor the operation and condition of downhole devices including electrical submersible pumps and flow control devices. In one embodiment, a common fluid line is used to monitor downhole parameters and to operate hydraulically-operated devices.

Abstract: A new method is disclosed for evaluating the efficiency of a sweep for removing cuttings from a borehole in a subterranean formation during a drilling operation. The method evaluates sweep efficiency on a “mass in” versus “mass out” basis. The method uses downhole density readings taken with a pressure-while-drilling tool inserted in the drill string. Measurements of hydrostatic pressure are converted into equivalent circulating density measurements which in turn are used in calculating the sweep efficiency. The method affords real time estimates at the wellsite of the quantity of formation cuttings brought out of a wellbore by a sweep.

Abstract: A torque swivel apparatus. The apparatus includes an upper body assembly secured to the lower end of a locking swivel of the type used in wireline operations. The upper body would engage into a lower body, the lower body secured to the drill string at the rotary table. The upper body would provide a pair of milled out wedge portions for accommodating a pair of wedge members in the lower body to engage therein during coupling. The apparatus further includes a plurality of cylinders positioned into the upper body with a piston member secured within each cylinder, so that each of the four faces of the wedge portions of the upper body accommodates a pair of pistons in its wall. The outer face of each of the pistons would make contact with each of the four faces of the wedge members of the lower body when coupling has occurred. The inner face of each of the pistons would mate with a line having fluid, which when acted upon would register force against the piston.

Abstract: A method for drilling a wellbore to assure the avoidance of a substantially adjacent known magnetic source comprising the steps of obtaining survey data for the path or trajectory of a known magnetic source; preparing a wellplan comprising a path or trajectory for a second wellbore to be drilled, from the survey data and the wellplan, computing expected values of one or more parameters of the magnetic field to be encountered along a second wellbore during drilling operations, in association with drilling a second wellbore, measuring components of a magnetic field encountered and computing one or more magnetic field parameters at a series of survey points along the wellbore path or trajectory; and determining if measured values differ systematically from expected values, thereby indicating a deviation from the planned wellpath.

Abstract: A well drilling system with a miniature directional indication sensor capable of operating at elevated temperature. The present invention is implemented with power supply, sensor drive and sense circuits in thick film or multi-chip module electronic assemblies, mounted on a chassis with a high resonant frequency. The thick film or multi-chip module electronics assemblies also contribute to increased shock and vibration resistance. Sensor drive and sense functions may be implemented in one or more application specific integrated circuits and integrated with multi-chip module electronics assembly. Analog-to-digital conversion of sensor signals is implemented in a voltage-to-digital converter circuit provided by the present invention. Furthermore, the present invention eliminates data lag between channels by providing simultaneous sampling of all the sensor channels.

Abstract: The present invention provides an apparatus and method for minimizing movement of a drill string during MWD with vibration-sensitive instruments comprising conveying a drill string into a borehole with a sensor mounted on the drill string for sensing a parameter of interest of a formation. A clocked controller is disposed on the drill string for controlling timing of the sensor; and a second clocked controller is disposed at a surface location. During drilling operations, the clocked controllers are synchronized such that the surface controller is performing certain tasks in timed sequence with the sensor even though the surface controller is not connected to the sensor.

Abstract: An accelerometer caliper while drilling arrangement comprising a drill bit having an axis of rotation and a gauge region, a caliper tool body, a first accelerometer mounted upon the caliper tool body and arranged to measure acceleration in a first direction, and a second accelerometer mounted upon the caliper tool body and arranged to measure acceleration in a second direction orthogonal to the first direction, wherein the caliper tool body and the drill bit are coupled to one another in such a manner that the first and second accelerometers are mounted in a known relationship to the drill bit.

Abstract: An accelerometer caliper while drilling arrangement comprising a drill bit having an axis of rotation and a gauge region, a caliper tool body, a first accelerometer mounted upon the caliper tool body and arranged to measure acceleration in a first direction, and a second accelerometer mounted upon the caliper tool body and arranged to measure acceleration in a second direction orthogonal to the first direction, wherein the caliper tool body and the drill bit are coupled to one another in such a manner that the first and second accelerometers are mounted in a known relationship to the drill bit.

Abstract: A method is disclosed that provides a stable invert emulsion for an oil-based drilling fluid with an environmentally friendly additive that effectively eliminates shale hydration and consequent borehole erosion. The additive is preferably potassium formate, although other formates or acetates may be substituted. In the method, the potassium formate is dissolved in the water phase of the emulsion in lieu of other less environmentally friendly salts such as sodium chloride. The water activity of the emulsion and of the formation being drilled is monitored during drilling so that additional formate may be added as needed to maintain such water activities in balance. That is, preferably, the water activity of the potassium formate will be the same as or less than the water activity of the formation.

Abstract: This invention relates to a device for measuring the flow rate of spoil from a drilling brought to the surface by means of a drilling fluid. The device comprises means of collecting the spoil and means of continuously measuring the weight of spoil collected. The means of collecting the spoil comprise a receptacle in the shape of bucket articulated about a spindle and means of tilting the receptacle in such a way that the bucket is emptied. The measurement means comprise a measuring cell connected to the tilting means in order to measure a stress proportional to the weight of the spoil collected. The invention also relates to a method for the application of a measurement of the spoil flow rate from a drilling.

Abstract: A method is provided for determining the rotational stiffness of a drill string for drilling of a borehole in an earth formation, the drill string having a bottom hole assembly (BHA) and an upper end driven by a rotational drive system. The method comprises the steps of determining the time derivative of the drill string torque during drilling of the borehole at a selected time when stick-slip of the BHA occurs, determining the nominal rotational speed of the drill string at an upper part thereof and at said selected time, and determining the rotational stiffness of the drill string from a selected relationship between said time derivative of the drill string torque and said nominal rotational speed at the upper part of the drill string.

Abstract: A method and apparatus for transferring data from a logging tool to a surface computer that involves attaching a stand-alone data dump device to the logging tool after the logging tool has gathered data about downhole parameters. After attaching the data dump device, data contained in a memory of the logging tool is copied to a memory of the data dump device. In one embodiment, once data copying between the logging tool and data dump device is complete, the data dump device is disconnected from the logging tool and connected to a surface computer which reads the data previously copied to the data dump device. A second embodiment of the data dump device has a radio frequency communication link between the surface computer and the data dump device to allow a wireless communication between the surface computer and the data dump device and/or logging tool.

Abstract: A method for determining the existence of a whirling condition during drilling of a borehole provides real time determination of destructive conditions of a bottom hole assembly during drilling. The method measures the acceleration of the bottom hole assembly to determine one or more acceleration values. Sensors also measured with rotation speed of the bottom hole assembly to determine at least one rotation of speed value. Based upon this information calculations are performed to determine a radius or diameter of rotation in the time domain which will indicate and identify the whirling condition within the bottom hole assembly. Types of whirl conditions identifiable are forward and backward whirl with and without slip. The method assumes forward whirl and backward whirl and creates a plot for each then overlaps the plot which provides an accurate representation of the condition of the bottom hole assembly while drilling.

Abstract: A directional drilling control system allows dynamic orientation of downhole drilling equipment in unstable or corrupt natural magnetic fields without the use of gyroscopic measurement devices. The system is especially suited for sidetracking wells. The system includes a permanent or retrievable whipstock having referencing magnets embedded along the centerline of its face, and a measurement while drilling (MWD) instrument assembly. The instrument assembly contains at least one sensor which can accurately determine orientation of the mud motor relative to the reference magnets. The relative positioning of the mud motor is transmitted to the surface by way of a steering tool or MWD telemetry system. The direction of the mud motor or tool face is adjusted by turning the drill pipe at the surface. As drilling progresses, shifts in the orientation of the mud motor due to reactive torque at the drill bit will be indicated in real time so that adjustments may be made at the surface as required.