Abstract: A printing pressure adjustment system and a method for adjusting the pressure applied by a print head against a backup member are disclosed. The adjustment system includes an elongated member that is slidably displaceable with respect to an outer surface of the print head. The elongated member has an inclined bearing surface on which a biasing member is positioned in order to apply a force to the elongated member. The elongated member includes a load transfer surface for transferring the biasing force to the print head.

Abstract: A data gathering computer and host data display computer interface system, methodology and protocol are described that utilize a shared control program. The data gathering computer uses this program to determine what measurements are to be made and when and how the data is to be compressed into its data storage. The host display and analysis computer receives and utilizes the control program and the stored data from the data gathering computer, and expands the stored data responsive to the control program, and reconstructs the value and engineering units of the values measured as well as the time that the measurements were made. By passing the control program gathered by the data gathering computer, a single display computer program is all that is needed to display any number of completely different data streams from any number of data gathering computers.

Abstract: A retrievable radiation source carrier assembly for a logging while drilling tool is disclosed. The carrier includes a solid rod or member of high strength and low elastic modulus that connects the housings of at least two radiation sources. In a preferred embodiment, the carrier includes a sheath of high performance thermoplastic that covers the rod from the upper source to the lower source. The sheath provides the carrier with a smooth outer surface and a substantially constant diameter that resists the accumulation of mud particulate buildup thereon. The sheath also provides a low friction surface which allows improved ease of insertion and removal of the radiation source carrier into and from the internal source passageway of the LWD tool.

Abstract: A magnetic mark on a cable is subject to loss of intensity. The present disclosure provides for remarking. It utilizes a detector which responds to passage of a magnetic mark on the cable. A coil for remarking is located at a specified and measured distance from the detector. Through the use of measuring wheels in contact with the cable providing data to a computer, the cable traverses from the detector to the marking coil, and a marker control circuit is timely operated to place a new mark on the cable. The new mark is placed coincident over the prior mark and has greater intensity to renew the magnetic marks on the cable.

Abstract: A seismic logging system for VSP or cross well data capture set forth. It is comprised of M duplicate recording stations connected serially below a main structure suspended on a logging cable. Each of the recording stations preferably includes orthogonally arranged displacement transducers, and they are in turn connected with suitable amplifiers, filters and converters to form digital words, and the digital words are recorded in organized fashion in a memory. A telemetry unit is connected to that memory for transfer of data. This data transfer takes place over a short distance into the main unit, and the main unit includes a much larger memory for storing and holding data from M recording stations deployed along and there below in the well borehole, and further including telemetry means for transfer of data along the logging cable.

Abstract: An apparatus and method for obtaining a spontaneous potential curve, which pparatus is comprised of: (a) an elongated body: (b) a series of vertically spaced electrodes for measuring electrical potential, wherein one of the electrodes is a reference electrode; and (c) a means for recording or transmitting the various electrical potentials to the surface. Preferably the apparatus is part of drillstring for taking measurements while drilling.

Abstract: A method and apparatus for acquiring acoustical data from a borehole and is especially useful in carrying out tomogrphy surveys. The borehole digital geophone (BDG) tool of the present invention is capable of operating from a standard, 7-conductor logging cable with no special cables being required since the individual digital geophone modules (DGM) which form the BDG tool are connected together by short, separate lengths of the same 7-conductor cable. Each DGM acquires, digitizes, stacks, and stores data generated by its own three-component geophone assembly prior to transmitting these signals to the surface over a dedicated conductor in the cable thereby substantially increasing the sample rate of the tool which, in turn, substantially reduces the field time to run a tomography survey.

Abstract: A method and apparatus are described for removing noise by smoothing fine resistivity measurements made with a tool from inside a borehole penetrating an earth formation. Pixel values representative of the resistivity measurements are examined to determine the directions of features in the measurements and a smoothing of the pixel values is then made along the measured directions. The orientations of the features are obtained with a similarlity investigation of pixels in sub-array windows along parallel lines whose slope is varied. Optimal slope lines along which the pixel values in a window best resemble each other are determined as the direction of the features. Smoothing is done along the optimal slope lines. Substantially noise free pixel measurements are obtained to enable subsequent automatic signal processing such as the detection of edges between layers of different resistivity. The edges are recorded with an emphasis on a visual display for enhanced visual analysis.

Abstract: A data acquisition apparatus includes two microcomputers interconnected by a shared dual access digital storage device. One microcomputer obtains the data related to the monitored condition, stores it in the digital storage device, and modifies a status word which is monitored by the other microcomputer. When the other microcomputer detects a change in the status word, it takes the data from the shared digital memory and moves it into its own memory for subsequent use or transfer. The data acquisition apparatus also includes, in a preferred embodiment, analog switches and a digital to analog converter by which external analog devices can be controlled to change the monitored operation.

Abstract: A method and apparatus allows dynamic data to be recorded in a drill string for later playback at the surface. The system includes a transducer located in a sub in the drill string which provides electrical responses to a analog to digital converter. A timer circuit provides timer pulses to the converter to cause the response to be converted into a digital value for storing in a recorder. The timer pulses are also used to address the memory location. The timer circuit has the ability to provide a variable number of timer pulses at a variable frequency and at variable intervals. A surface timer circuit provides simultaneous timer pulses to a counter to indicate at the surface which memory location is being filled at any given time.

Abstract: A portable terminal for plugging into a well production control system for displaying data from the control system and for entering data into the control system. A liquid crystal display module on the terminal displays both graphic and printed data. A keyboard on the terminal provides a means for entering data and control signals into the control system. A temperature compensating circuit adjusts the brightness contrast on the display module so the terminal can be used outdoors over a wide range of temperatures.

Abstract: The apparatus and method of the present invention pertain to visual presentation systems employing scan lines, wherein each scan line is divisible into sets of points respectively corresponding to locations at which well measurements are made. The resulting sets are shaded in accordance with the value of the respective measurements. Harsh transitions between adjacent sets are removed by having a parameter evaluated for each point of the scan line in accordance with (a) the spatial relationship of a subset of points which includes the point to adjacent sets of points; and (b) the well measurement made at the location to which the point corresponds. The parameter value is compared with a randomly or pseudo-randomly generated number, and the point is marked if the result of the comparison satisfies a preselected relationship. The parameter is evaluated and the comparison is made for all other points in the scan line.

Abstract: Apparatus for detecting fluid pound in a sucker-rod oil well, using values of sucker-rod position and of sucker-rod load to calculate a reference position and a selected load value. The apparatus continually updates the reference positions and selected load values to compensate for drift in characteristics of transducers used in determining rod load and rod position and for a gradual change in well characteristics. When the sucker-rod moves downward to the updated reference position, the actual rod load is checked against the updated selected value and a warning signal develops when the amount of load exceeds the updated selected value.

Abstract: An oilfield monitor and recorder system providing marker positioning using a leadscrew, a stepper motor, a position sensor, driver and control. The control provides zero, span, slew and range functions. The rate input scaling provides calibration, percent, sum to monitor and sum to recorder controls. The pressure input scaling provides zero, span and calibration controls, therefore the input signals are calibrated and scaled for presentation to display and marker control circuits. Record advancement uses tractor drives, stepper motor, precision time base, driver and control in order to provide an accurate time record relationship. This portable battery powered system and apparatus is housed in a briefcase size enclosure. The electrical signals obtained from a plurality of physical conditions are processed, recorded and displayed on respective recorder and display channels, which particularly meets the oilfield stimulation service industry requirements for a portable monitoring and recording apparatus.

Abstract: Method and apparatus for entering control points relative to a dynagraph of a well pumping unit using the position of a beam and a pen holder of an XY plotter. The beam and/or the pen holder is physically moved to a desired location and an "enter" button is pressed to enter a value corresponding to an X or a Y position and another button is used to enter the other corresponding position value. The entered point is used to control operation of the well.

Abstract: A borehole logging tool employs an energy transmitter and receiver for scanning a borehole with energy pulses. An orientation pulse is produced each time the tool rotates past a predetermined orientation position. The time period between orientation pulses is measured and divided into a plurality of discrete intervals. Sine and cosine functions are generated for the measured time period having a sine and cosine value corresponding to each of the discrete intervals. The sine and cosine functions are used to produce sweep functions for controlling the outward sweep of the electron beam of a PPI display device so as to produce a circular rotating pattern in which each revolution corresponds in time to a measured time between orientation pulses. The output of the receiver modulates the electron beam sweep to generate a visual display of the azimuthal scan of the borehole.

Abstract: A borehole logging system includes a borehole logging tool, a logging tool depth encoder for indicating rate of movement of the logging tool, a moving recording medium, and a recording encoder for indicating the actual rate of movement of the recording medium. The logging rate indicated by the depth encoder is used to provide a signal representative of a desired recording rate. This desired recording rate is compared to the actual recording rate and correction made to the recording rate when there is a variance between such desired and actual recording rates.

Abstract: Method and apparatus for recording and subsequent playback of selected dynagraphs for wells employing sucker-rod pumping units to determine well faults which cause well shutdown. Calibration data from well monitoring equipment is stored in a first "endless tape" type of memory during calibration of the well and operation data from the monitoring equipment is stored in a second "endless tape" memory during well operation. After well shutdown the stored data can be retrieved and the operation data stored immediately prior to well shutdown compared with calibration data to determine what type of fault caused well shutdown.

Abstract: An improved well logging system and method is provided for deriving and visibly displaying a recordable representation of a comprehensive lithological profile of the earth materials traversed by a borehole. In a particular form of the invention, all logging measurements are derived in digital form and on the same depth-dependent bases, such that measurements taken during one trip through the borehole may be combined or processed with other logging measurements taken during a different trip through the same borehole of interest, such that all of the measurements may then be processed at one time to derive the various lithological indications sought to be provided.An improved monitoring system and technique is further provided, such that those logging measurements and lithological relationships of interest may also be correlatively displayed on a real-time basis with respect to at least some of the logging measurements from which they are derived.

Abstract: Apparatus and method for recording seismic signals on a logging chart as a function of the depth of a logging sonde within a well bore includes apparatus for analyzing the seismic signals. The method utilizes the recording of information relating to the slope of a seismic signal received from the sonde. A recording trace is made using successive horizontal sweeps with no vertical deflection, and presence of a mark on the recording can indicate a positive slope for the seismic signal, and the absence of a mark can indicate a negative slope. An apparatus of the present invention utilizes this method to record well logging information obtained from seismic signals.

Abstract: Real time responsive devices are mounted at the inlet to an in-hole motor to measure the interval of time during which drilling fluid circulates through the motor.

Abstract: An apparatus for measuring the rate of movement of one object with respect to another, such as a drilling rate recorder used to measure the rate of penetration of a drill bit during drilling operations. One embodiment of the invention includes a frame, a motion imparting means for imparting motion from a drill string; a first arm having one end pivotally mounted on the frame, a second arm pivotally mounted on the first arm, a first cam attached to the motion imparting means and adapted to cause the second arm to pivot about the first arm, and a recording means.

Abstract: A logging tool recording system counts and converts depth pulses into a digital coded format. Such digital coded format is converted to a serial digital word for recording on an analog recorder. During playback the digital serial word is converted back into a digital coded format for reproduction by means of a visual digital display.

Abstract: A system and method for processing and displaying well-logging data provides direct indications of various lithological characteristics in conjunction with symbolic representatives of formation lithologies. Preselected programming of a two-dimensional symbol matrix into a memory device provides symbol flexibility. Geometric symbol matrices corresponding to different formation characteristics are digitally stored. When a preselected relationship occurs between lithological characteristics, the particular preselected matrix corresponding to the relationship is repetitively retrieved and displayed between the lithological characteristics curves. Because a relatively small digital matrix pattern may be used and repeated, only a small amount of storage is required for each symbol.

Abstract: A method which determines output parameters (such as porosity .phi. or water saturation S.sub.w of formations) from a set of logging measurements taken at each level of a borehole is proposed.Measurement and response equation uncertainties of each logging apparatus are determined at each measurement level. Assumed values of the output parameters are chosen and, applying the response equations, calculated values of the measurements are determined. The calculated values of the measurements and the actual measurements are then compared to determine deviations which are weighted by factors calculated from the previously determined uncertainties. An incoherence function is determined from the weighted deviations and a number of "a-priori" constraints. Minimization of the incoherence function gives the most probable output parameters whose uncertainty is in turn calculated.

Abstract: A method and apparatus for accepting analog voltage signals from a reciprocating liquid well pump and digitizing the signals and storing the signals for playback at a later time. A receiving circuit accepts two analog signals, one of which is proportional to the load in the polished rod, the other of which is proportional to the displacement of the polished rod. Simultaneously the two analog signals are digitized by means of an analog to digital converter and the digital data is stored on a digital memory integrated circuit. The digital memory may be replayed through a digital to analog converter into an x-y plotter. Digital latches and counters detect the start and end of a pumping cycle to insure that one full cycle of the reciprocating pump is stored in the digital memory. Timing circuitry strobes the load and displacement data into the digital memory in equal time increments to allow time related methematics to be performed by a computer.

Abstract: A system (10) for continuously analyzing drilling mud circulating through a borehole comprises a sampling chamber (12) through which flows the return mud, a sensor (16) mounted in the sampling chamber for detecting hydrogen gas percolating out of the drilling mud and for producing a signal representative of the concentration of hydrogen, and a recorder (34) for recording the signal from the sensor over a period of time. Appropriate circuitry within a control panel (20) is connected between the sensor (16) and recorder (34). In the preferred embodiment of the invention, the recorder (34) comprises a clock driven disk recorder.

Abstract: A method is disclosed for determining the location of hydrocarbon reservoirs which comprises the steps of drilling boreholes along a linear path to a depth below the weathered zone, sampling the soil and drilling fluid found at the bottom of the boreholes for the presence of constituents, such as gaseous hydrocarbons and bacteria, indicating the presence of hydrocarbons, detonating explosive charges at the bottom of the boreholes to seismically determine the geological structure of the test area and plotting the resultant values for the constituent presence and geological structure data, with the plot having a common axis representing the linear path along which the boreholes are drilled. This method permits multiple and distinct indications of the presence of hydrocarbon reservoirs to be integrated to more uniformly and reliably predict the presence of a hydrocarbon reservoir.

Abstract: A method and apparatus for acoustical logging wherein a plurality of transducers are spaced circumferentially in a plane perpendicular to the borehole and in close proximity to the wall of the borehole. Numerous circumferential acoustic transmission paths are defined by using some of the transducers as transmitters and others as receivers. Ultrasound is transmitted and received separately along each of the paths and amplitudes of the received waves are separately recorded to provide a side-by-side comparison of the signals. The received waves may be comprised of shear waves and compressional waves, and the shear wave amplitude may be recorded to the exclusion of later arriving waves. Proper spacing of the transmitters and receivers will produce a complete circumferential acoustic log of the borehole that can be used to detect the presence of vertical fractures.

Abstract: In the representative embodiments of the new and improved methods and apparatus disclosed herein for controlling multicharge perforating guns or core-sampling guns, the gun-control system of the present invention includes a selectively-operable multi-contact switch assembly operative from the surface to sequentially connect a group of electrically-detonatable charges into a firing circuit for consecutively firing the charges on the gun. An array of serially-connected Zener diodes cooperatively associated with the switch assembly provides indications at the surface showing which of the several charges is then connected into the gun-firing circuit. The new and improved gun-control system also includes a shot-monitoring system which provides additional surface indications from which it can be determined whether the charges on the gun are being successfully fired and, at least approximately, that they are being consecutively fired.

Abstract: A dynamometer for monitoring the tension in a pair of spaced, elongated members. A pen, actuated by a sensor means, measures the tension in the pair of spaced, elongated members, and places indicia upon a continuously moving chart. The indicia is related to the magnitude of the measured tension and is in the form of spaced-apart, individual curves or plots. Hence the pen contacts the chart for a first time interval; and thereafter, the pen is lifted from the chart for a second time interval so as to cyclically place the indicia upon the chart at successive intervals of time. More specifically, the dynamometer measures the tension in a rod string. The rod string is reciprocated by a pumpjack unit located above the ground and drives a downhole pump.

Abstract: According to one embodiment, distinctive indicia having a "three-dimensional" appearance and representative of well logging data is produced by a CRT (Cathode-ray tube) recorder by modulating both the intensity and position of the sweeping electron beam in response to variations in the data. In another embodiment, distinctive indicia in the form of a vector or arrow representative of the data is produced by sweeping the CRT electron beam in such a way that it defines an increasing spiral pattern. The electron beam is then turned on for a short pulse at the same angular position of each cycle of the spiral. For purposes of synchronization, in each of the above embodiments the beam sweep is initiated by a recurring event, such as a pulse indicative of a given incremental change in the depth level from which the data was derived.

Abstract: In accordance with illustrative embodiments of the present invention, data signals, particularly well logging data in analog or digital form, is recorded by a cathode ray tube recorder. A representation of the CRT beam is repetitively swept across a recording medium while being modulated with representations of the well logging signals. This modulation varies as a function of the rate of change of the well logging signals to produce an even density recording. Coding of the recording lines or traces and the areas between selected traces can be accomplished. This coding of the lines is also varied in dependence on the well logging signal rate of change to produce a uniform coding presentation. Depth information can be recorded on the recording medium by writing depth numbers and depth lines on the record medium. Moreover, a section by section visual presentation of the data can be produced while it is being recorded.

Abstract: A system for performing wellbore telemetry operations wherein a communication link between a subsurface location in a well and the location substantially at the surface is established and maintained through electromagnetic coupling between two insulated electric conductors. The first conductor is electrically coupled to a transmitter, normally located at the subsurface location, and extends upwardly in the well. The second conductor is electrically coupled to a receiver, normally at the surface location, and extends down into the well. Normally, the two conductors will overlap along a substantial portion of the lengths thereof. As the well is drilled deeper and the drill string is lengthened, the transmitter and the first conductor follow the progression of the wellbore into the earth, thereby reducing the overlap between the first and second conductors. When the two conductors cease to overlap, the second conductor may be lengthened to re-establish the overlap.

Abstract: In accordance with illustrative embodiments of the present invention, well logging data in analog or digital form is recorded by a cathode ray tube recorder. A representation of the CRT beam is repetitively swept across a recording medium while being modulated with representations of the well logging signals. This modulation varies as a function of the rate of change of the well logging signals to produce an even density recording. Coding of the recorded lines or traces and the areas between selected traces can be accomplished. This coding of the lines is also varied in dependence on the well logging signal rate of change to produce a uniform coding presentation. Depth information can be recorded on the recording medium by writing depth numbers and depth lines on the record medium. Moreover, a section by section visual presentation of the data can be produced while it is being recorded.

Abstract: A method and apparatus for providing a signal when equipment being run into or out of a well on a magnetizable wire line reaches a previously visited point in the well below the surface. With the equipment at the point in the well to be revisited, a magnetic mark is applied on the wire line at an appropriate spot at the surface. The magnetic mark may be of one or more dipoles and in the case of three or more dipoles they are arranged in close proximity along the length of the wire line with alternately opposite polarities and on a common axis of polarity, with said axis substantially paralleling the length of the wire line. Subsequently, in running the equipment in or out, at least one of the magnetic dipoles is detected at the same appropriate spot at the surface and is used to actuate a signaling device.

Abstract: An acoustic velocity logging tool employs a transmitter and a pair of receivers. Acoustic pulses from the transmitter pass through the formation surrounding the borehole to the receivers. The received signals, along with control signals, are transferred to an uphole recording system. A record unit operates to apply these receiver and control signals to a magnetic tape recorder. A playback unit transfers the recorded receiver signals to the intensity modulation input of a cathode-ray oscilloscope and, in response to the recorded control signals, applies a trigger pulse to the sweep input of the cathode-ray oscilloscope, successive sweeps of the cathode-ray oscilloscope being intensity modulated alternately by the recorded receiver signals of the pair of receivers. A film recorder makes a continuous film recording of the receiver signals as they appear as variable-density traces on the face of the cathode-ray oscilloscope to provide a two-receiver, variable-density recording. A .DELTA.

Abstract: An acoustic velocity logging tool employs a transmitter and a pair of receivers. Acoustic pulses from the transmitter pass through the formation surrounding the borehole to the receivers. The received signals, along with control signals, are transferred to an uphole recording system. A record unit operates to apply these receiver and control signals to a magnetic tape recorder. A playback unit transfers the recorded receiver signals to the intensity modulation input of a cathode-ray oscilloscope and, in response to the recorded control signals, applies a trigger pulse to the sweep input of the cathode-ray oscilloscope. A film recorder makes a continuous film recording of the receiver signals as they appear as variable-density traces on the face of the cathode-ray oscilloscope.

Abstract: An acoustic velocity logging tool employs a transmitter and a pair of receivers. Acoustic pulses from the transmitter pass through the formation surrounding the borehole to the receivers. The received signals, along with control signals, are transferred to an uphole recording system. A record unit operates to apply these receiver and control signals to a magnetic tape recorder. A playback unit transfers the recorded receiver signals to the intensity modulation input of a cathode-ray oscilloscope and, in response to the recorded control signals, applies a trigger pulse to the sweep input of the cathode-ray oscilloscope, successive sweeps of the cathode-ray oscilloscope being intensity modulated alternately by the recorded receiver signals of the pair of receivers. A film recorder makes a continuous film recording of the receiver signals as they appear as variable-density traces on the face of the cathode-ray oscilloscope to provide a continuous two-receiver, variable-density recording.