초록 ▼

An apparatus and method is presented for establishing electrical connection to permanent downhole oilfield installations using an electrically insulated conducting casing. Current is caused to flow in the casing by a source on the surface connected to the casing. One or more permanent downhole insta

An apparatus and method is presented for establishing electrical connection to permanent downhole oilfield installations using an electrically insulated conducting casing. Current is caused to flow in the casing by a source on the surface connected to the casing. One or more permanent downhole installations are electrically connected to the casing, and the electrical connection to the casing is used to power the downhole installations. The downhole installations also inject a signal into the insulated casing that passes via the casing to a surface readout which detects and records the downhole signals.

대표청구항 ▼

An apparatus and method is presented for establishing electrical connection to permanent downhole oilfield installations using an electrically insulated conducting casing. Current is caused to flow in the casing by a source on the surface connected to the casing. One or more permanent downhole insta

An apparatus and method is presented for establishing electrical connection to permanent downhole oilfield installations using an electrically insulated conducting casing. Current is caused to flow in the casing by a source on the surface connected to the casing. One or more permanent downhole installations are electrically connected to the casing, and the electrical connection to the casing is used to power the downhole installations. The downhole installations also inject a signal into the insulated casing that passes via the casing to a surface readout which detects and records the downhole signals. ight receiver and said light transmitter; and means for distinguishing between smoke and other foreign bodies which are located in an area around said scattering point. 2. A scattering light as defined in claim 1, wherein said means for distinguishing between smoke and other foreign bodies includes a processor for analysis of a time course of receiving signals of said light receiver, said processor being connectable to said light receiver. 3. A scattering light as defined in claim 1, wherein said means for distinguishing between smoke and other foreign bodies includes optical means provided on said light receiver which couple scattering signals from several scattering regions in one area around the scattering into said light receiver. 4. A scattering light as defined in claim 3, wherein said optical means include a facette mirror. 5. A scattering light as defined in claim 1, wherein said light receiver is formed as a photo receiver array having at least two photo receiver elements. 6. A scattering light as defined in claim 5, and further comprising a lense system arranged before said photo receiver array. 7. A scattering light as defined in claim 1, wherein said light transmitter is formed as a variable frequency light source, said variable frequency light source, depending on scattering signals from a transmitter control, emitting light with a changeable wavelength. 8. A scattering light as defined in claim 1, and further comprising an amplitude modulator connectable with said light transmitter. 9. A scattering light as defined in claim 1, and further comprising an ultrasound sensor having an ultrasound transmitter and an ultrasound receiver, said ultrasound sensor being arranged so that it monitors an area around said scattering point. 10. A scattering light as defined in claim 9, wherein said ultrasound sensor is operatable with an echo operation. the hazard alert flasher unit is intended to replace the standard element presently used in highway vehicles to generate the turn signal and hazard flash pulse. A second version of the hazard alert flasher can be used to control the flash rate of free-standing emergency electric lanterns, illuminated emergency warning triangles, and LED substitutes for pyrotechnic flares. The proposed hazard alert flash pattern consists of three or more short flashes followed by a longer pause.