摘要:
Long utility holes, for gas lines, electrical conduit, communications conduit and the like, may be bored or pierced horizontally through the earth, particularly under obstacles, such as buildings, streets, highways, rivers, lakes, etc. Such holes may be bored by an underground drilling mole (underground percussion drill) supported on a hollow drill rod and supplied with compressed air through the rod to operate an air hammer which strikes an anvil having an external boring face, preferably constructed to apply an asymmetric boring force. The drill rod is operated by a drill rig on the surface or recessed in special pit for horizontal drilling and provides for addition of sections of pipe or hollow rod as the boring progresses. The asymmetric boring force causes the boring path to curve and, when straight line drilling is needed, the drill rod is rotated to counteract the asymmetric boring force. An alternative boring tool utilizes an expander supported on a solid or hollow drill rod and having a base end supported on and larger in diameter than the rod and tapering longitudinally forward therefrom. It may have a uniform extension protruding a short distance forward. The tool penetrates the earth upon longitudinal movement of the drill rod.
摘要:
Long utility holes, for gas lines, electrical conduit, communications conduit and the like, may be bored or pierced horizontally through the earth, particularly under obstacles, such as buildings, streets, highways, rivers, lakes, etc. Such holes may be bored by an underground drilling mole (underground percussion drill) supported on a hollow drill rod and supplied with compressed air through the rod to operate an air hammer which strikes an anvil having an external boring face, preferably constructed to apply an asymmetric boring force. The drill rod is operated by a drill rig on the surface or recessed in special pit for horizontal drilling and provides for additional sections of pipe or hollow rod as the boring progresses. The asymmetric boring force causes the boring path to curve and, when straight line drilling is needed, the drill rod is rotated to counteract the asymmetric boring force. An alternative boring tool utilizes an expander supported on a solid or hollow drill rod and having a base end supported on and larger in diameter than the rod and tapering longitudinally forward therefrom. It may have a uniform extension protruding a short distance forward. The tool penetrates the earth upon longitudinal movement of the drill rod.
摘要:
A new and improved air motor operated rotary earth drilling tool for use with a source of high pressure, high volume compressed air has a circulation control housing, a motor housing, a reduction gear housing, and a bearing housing connected longitudinally in series. The circulation control housing is connected to high pressure, high volume, compressed air and has an outlet opening into the motor housing, and an exhaust opening for discharge of compressed air for flushing cuttings and debris from a bore hole which is controlled by longitudinal movement of an inlet tube. The motor housing has a motor chamber and a sliding vane rotor with a rotary shaft extending into the reduction gear housing. A planetary reduction gear receives the rotor shaft and has a low speed, high torque output shaft extending into the bearing housing. A passageway conducts compressed air around the planetary reduction gear for cooling. A radial and thrust bearing pack in the bearing housing is connected to the planetary reduction gear output shaft. A hollow, rotary drill bit sub extends into the bearing housing and is supported on the bearing pack for rotation by the planetary reduction gear. Part of the compressed air operating the motor and cooling the planetary reduction gear is discharged through the drill bit sub and part flows though the bearing pack for cooling and discharge into the bore hole.
摘要:
A test stand has a base supporting standards on which are mounted a crossbar and an adjustably locatable header. The header supports an actuator for raising and lowering the crossbar which holds V-blocks for engaging the handles of an impact or impact-rotary tool and which applies downward pressure to the tool. The tool chuck is fitted to the top of a guide rod whose lower end passes with a sliding fit through a disc to which it is keyed and bears against a piston in an hydraulically pressurized cylinder. Sensors detect rotation of the disc and movement of the piston to provide information to a computer as to impact energy and rotary speed. A manifold fitted with sensors for temperature, pressure, and flow rate supplies operating air to the tool. The computer includes a database with stored information as to past history of the tool and the manufacturer's recommended operating specifications to which the measured data is compared.
摘要:
A steering system is disclosed for percussion boring tools for boring in the earth at an angle or in a generally horizontal direction. The steering mechanism comprises a slanted-face nose member attached to the anvil of the tool to produce a turning force on the tool and movable tail fins incorporated into the trailing end of the tool which are adapted to be selectively positioned relative to the body of the tool to negate the turning force. The fins are constructed to assume a neutral position relative to the housing of the tool when the tool is allowed to turn and to assume a spin inducing position relative to the housing of the tool to cause it to rotate when the tool is to move in a straight direction. Turning force may also be imparted to the tool by an eccentric hammer which delivers an off-axis impact to the tool anvil. For straight boring, the tail fins are fixed to induce spin of the tool about its longitudinal axis to compensate for the turning effect of the slanted nose member or eccentric hammer. When the fins are in the neutral position, the slanted nose member or the eccentric hammer will deflect the tool in a given direction. The fins also allow the nose piece to be oriented in any given plane for subsequent steering operation.
摘要:
A percussion boring tool is disclosed for boring in the earth at an angle or in a generally horizontal direction. The tool has a steering mechanism substantially as shown in a copending patent application and a cylindrical body with overgage sleeves located over a portion of the outer body affixed so that they can rotate but cannot slide axially. The overgage areas at the front and back of the tool, or alternately, an undergage section in the center of the tool body permits a 2-point contact (front and rear) of the outer housing with the soil wall as opposed to the line contact which occurs without the undercut. The 2-point contact allows the tool to deviate in an arc without distorting the round cross-sectional profile of the pierced hole. Thus, for a given steering force at the front and/or back of the tool, a higher rate of turning is possible since a smaller volume of soil needs to be displaced.
摘要:
A wireless downhole electromagnetic data transmission system and method utilizes microprocessor controlled frequency synthesis for two-way communication between the surface and a downhole guided boring or drilling apparatus in the range of from 100 Hz to 100 KHz. A non-magnetic downhole probe unit connected between a drill motor or drill bit and the drill string contains data gathering and transmission components including accelerometers which measure the earth's gravity vector and fluxgate magnetometers which read the earth's magnetic field and serve as power line proximity sensors. The drill pipe acts as an electrical lossy, single conductor with the earth forming the electrical return path. Sensory data gathered by the downhole probe is encoded in digital format and impressed upon the drill string using frequency shift keying of the electromagnetic energy waves and is picked off at the surface by a signal receiver-demodulator and message processor unit. The surface unit instructs the downhole probe to transmit multiple frequencies and selects one or more frequencies with the most favorable signal-to-noise ratio(s) in response to local conditions to maximize the transmission distance at a selective frequency band range and given transmitter power level and baud rate. The received signal is filtered, demodulated, processed and displayed at the surface and gravity and magnetic field vectors are combined with the created hole length to calculate x, y, and z hole coordinates and derive hole position vectors.
摘要:
A system of apparatus for use in a coring tool measures the height of a core sample being recovered and transmits data relative thereto to the surface of a formation concurrently during the coring operation. A transmitter of an electromagnetic ranging system rides atop a core sample being formed in the barrel chamber and a receiver member of the electromagnetic ranging system is fixed at a top end of the barrel it known distance above the transmitter. During the coring operation the transmitter transmits a fixed frequency signal to the receiver through drilling fluid disposed therebetween. The distance between the transmitter and receiver decreases and the amplitude of the transmitted signal changes as a function of the separation distance between the transmitter and receiver as the core sample enters the inner barrel and the height of the core sample within the barrel is determined as a function of time and depth. The pressure of the drilling fluid is modulated to transmit a series of pressure pulses from the barrel to the surface encoded to produce a binary digital or pulse-width modulation signal. The electromagnetic ranging system may be incorporated into a coring tool having a core bit disposed at a lower end and a full closure ball valve and core retention assembly movable to a closed position to close the bottom end of the inner barrel and prevent the loss of core collected in the inner barrel chamber.
摘要:
A downhole buried utility sensing and data transmission system for connection at the lower end of a drill string has sensors capable of detecting the existence of various different types of buried utilities and objects and making calculations as to the radial separation distance between the detected utilities and the drill head and transmitting data between the down hole drill head to the surface. The sensors respond to material properties used to construct the utility lines or the energy fields created by the operation of these lines (pipes and cables) or from the energy associated with transmission of the particular utility service, including sound energy resulting from fluid flow and electromagnetic energy from electric currents. The system can detect and distinguish the presence of ferromagnetic metallic objects including steel pipes and structures; non-metallic utility infrastructure including gas pipelines, concrete sewer lines, telecommunication lines, and cable systems outfitted with RF tracer lines and transmitters; energized AC and DC power cable systems; and determining the approximate range, relative azimuth, and elevation of the sensors relative to the detected utility or object. The system also supports automatic cessation of drilling operations by combining the warning information with microprocessor control of drill string rotation and thrust.
摘要:
Apparatus is disclosed for providing one hundred percent inspection of natural gas mains under operating flow conditions. The apparatus includes a scan unit assembly which is inserted into the gas main to collect data for the production of graphic images of the wall of the gas main. The scan unit includes a plurality of scan rollers, each containing an ultrasonic transducer, which traverse the surface of the wall defining the inner diameter of the gas main. The ultrasonic transducers transmit interrogating pulses into the wall of the gas main at a pre-determined spaced apart interval resulting in a helical scan pattern of interrogating pulses. The return pulses from the surfaces defining the inner diameter and outer diameter of the gas main and any imperfections and/or flaws within the wall of the main are received by the transducer and transmitted to a display unit for a visual indication (a tomograph) of the wall of the gas main.