摘要:
A coupling that makes electrical connections across a joint joining adjacent tubular members, such as drill pipe sections in a drill string. A male sleeve, made from an electrical insulating material, is attached to the male end of one pipe section. A number of axially spaced apart male contact members, such as ring segments or buttons, are formed on the outside surface of the male end. The male contact members are spring biased radially outward. Each of the male contact members is radially displaced from the axial centerline of the pipe section by a progressively increasing amount. A female sleeve, also made from an electrical insulating material, is attached to the female end of the other pipe section. A number of female contact members, such as ring segments or buttons, are formed on the inside surface of the female end. Each of the female contact members is radially displaced from the axial centerline of the pipe section by a progressively increasing amount. The axial spacing and radial displacements of the male and female contact members is such that when the pipe section are assembled by threading the male end into the female end, each male contact member makes electrical contact with its intended mating female contact member without ever having contacted any of the other female contact members. Deformable cleaning elements formed on one of the ends wipe clean the contact members formed on the other end as the joint is being assembled. The debris wiped clean is deposited in a groove located in front of the wiper.
摘要:
A latching system for maintaining the position of a component within a downhole drill string section during operation of a drill string. One preferred latching system embodiment has a shoe member including a cavity for receiving a component, a chamber opening into the shoe member cavity, an engagement member movable in the chamber between a retracted position and an engagement position, a first passage in fluid communication with the chamber and extending to an end surface of the shoe member, and a second passage extending from an outer side surface of the shoe member to the first passage. A pressure differential between pressure in the first passage and pressure in the second passage alters the position of the engagement member.
摘要:
A method and apparatus for communicating with a device downhole in a well, such as a bottom hole assembly in a drill string. Pressure pulses, such as those generated by the pistons of the mud pump, are transmitted through the drilling mud to a pressure pulsation sensor in the bottom hole assembly. The pressure pulsation sensor features a piezoceramic element that generates a varying voltage signal in response to the received pressure pulsations. The pressure pulsation sensor also has electronic components that allow it to analyze a characteristic of the pressure pulsations, such as their frequency. Based on its analysis of the pressure pulsations, the sensor can decipher a command from the surface, for example, that directs the steering of a steerable drill string, or that can determine whether the mud pumps are operating. If the mud pumps are not operating the sensor directs a microprocessor to reduce power to the bottom hole assembly electrical components, such as a measurement while drilling tool, thereby conserving battery power. The method and apparatus can also be used to control the operation of flow control valves in a multilateral well.
摘要:
A method and apparatus for transmitting information to the surface from down hole in a well in which a pulser is incorporated into the bottom hole assembly of a drill string that generates pressure pulses encoded to contain information concerning the drilling operation. The pressure pulses travel to the surface where they are decoded so as to decipher the information. The pulser includes a stator forming passages through which drilling fluid flows on its way to the drill bit. The rotor has blades that obstruct the flow of drilling fluid through the passages when the rotor is rotated into a first orientation and that relieve the obstruction when rotated into a second orientation, so that oscillation of the rotor generates the encoded pressure pulses. An electric motor, under the operation of a controller, drives a drive train that oscillates the rotor between the first and second orientations. The electric motor is located in an air-filled chamber whereas the major portion of the drive train is located in a liquid-filled chamber. The controller controls one or more characteristics of the pressure pulses by varying the oscillation of the rotor. The controller may receive information concerning the characteristics of the pressure pulses from a pressure sensor mounted proximate the bottom hole assembly, as well as information concerning the angular orientation of the rotor by means of an encoder. The controller may also receive instructions for controlling the pressure pulse characteristic from the surface by means of encoded pressure pulses transmitted to the pulser from the surface that are sensed by the pressure sensor and decoded by the controller.
摘要:
A method and apparatus for determining the concentration of a constituent in a fluid by directing a beam of light into the fluid and sensing the intensity of components of the light emerging from the fluid at various wavelengths. The light emerging from the fluid can be light that has been attenuated by absorption or induced by fluorescent radiation. The effect of scattering on the light is minimized by normalizing the component intensities, which are then applied to an algorithm incorporating weighting factors that weighs the influence that the intensity at each wavelength has on the determination of the concentration of the constituent for which the algorithm was developed. The algorithm is developed by a regression analysis based upon a plurality of known mixtures containing various concentrations of the constituent of interest.
摘要:
A method and apparatus for determining the concentration of a constituent in a fluid by directing a beam of light into the fluid and sensing the intensity of components of the light emerging from the fluid at various wavelengths. The light emerging from the fluid can be light that has been attenuated by absorption or induced by fluorescent radiation. The effect of scattering on the light is minimized by normalizing the component intensities, which are then applied to an algorithm incorporating weighting factors that weighs the influence that the intensity at each wavelength has on the determination of the concentration of the constituent for which the algorithm was developed. The algorithm is developed by a regression analysis based upon a plurality of known mixtures containing various concentrations of the constituent of interest.